WO2008003044A2 - Moniteur du profil comportemental humain et son procédé d'utilisation - Google Patents

Moniteur du profil comportemental humain et son procédé d'utilisation Download PDF

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WO2008003044A2
WO2008003044A2 PCT/US2007/072359 US2007072359W WO2008003044A2 WO 2008003044 A2 WO2008003044 A2 WO 2008003044A2 US 2007072359 W US2007072359 W US 2007072359W WO 2008003044 A2 WO2008003044 A2 WO 2008003044A2
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mice
locomotor
behavior
activity
dat
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PCT/US2007/072359
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WO2008003044A3 (fr
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William Perry
Mark Geyer
Arpi Minassian
Martin Paulus
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The Regents Of University Of California
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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/103—Detecting, measuring or recording devices for testing the shape, pattern, colour, size or movement of the body or parts thereof, for diagnostic purposes
    • A61B5/11—Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb
    • A61B5/1104—Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb induced by stimuli or drugs
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/103—Detecting, measuring or recording devices for testing the shape, pattern, colour, size or movement of the body or parts thereof, for diagnostic purposes
    • A61B5/11—Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb
    • A61B5/1113—Local tracking of patients, e.g. in a hospital or private home
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/16—Devices for psychotechnics; Testing reaction times ; Devices for evaluating the psychological state
    • A61B5/165—Evaluating the state of mind, e.g. depression, anxiety
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/16—Devices for psychotechnics; Testing reaction times ; Devices for evaluating the psychological state
    • A61B5/168—Evaluating attention deficit, hyperactivity
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B2503/00—Evaluating a particular growth phase or type of persons or animals
    • A61B2503/06—Children, e.g. for attention deficit diagnosis
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B2503/00—Evaluating a particular growth phase or type of persons or animals
    • A61B2503/40—Animals
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B2503/00—Evaluating a particular growth phase or type of persons or animals
    • A61B2503/42—Evaluating a particular growth phase or type of persons or animals for laboratory research

Definitions

  • the present invention relates to a translational approach to utilize measures characterizing rodent locomotor behavior for application to human locomotive behavior. More particularly, the present invention relates to an animal and human paradigm, namely, behavioral pattern monitor (BPM), and method of use thereof, for neuropsychiatric analyses, drug efficacy measurement, new drug evaluation, and assessment of cognition on mediations.
  • BPM behavioral pattern monitor
  • Bipolar Disorder is a highly recurrent and chronic psychiatric disorder that is characterized by states of mania and affects approximately 1% of the population.
  • BD is a national health issue as it shortens life expectancy, and causes functional impairment and disruption to social, occupational, and family life (Post et al 2003).
  • the underlying neural circuit abnormalities associated with BD are not well understood.
  • patients exhibit impulsive behavior, hypersexuality, pressured speech and flight of ideas, and motor hyperactivity, which are symptoms that result from the inability to inhibit behavior and thought (Goodwin & Jamison 1990).
  • Inhibition in the sensory, motor, and cognitive domain is critical for adaptive functioning in a constantly changing environment. Inhibition can be probed with different experimental approaches, which makes this construct amenable to studies in humans and animals.
  • DA dopamine
  • DA agonist-induced locomotor hyperactivity has long been used to model the mania phenotype in animals (Lyon 1991). Marked hyperactivity can be triggered in humans or rodents by DA psychostimulants such as amphetamine, which act via the DA transporter (DAT), suggesting that this DA mechanism may be involved in these behaviors. Indeed, amphetamine can induce relapse in remitted manic patients (Goodwin & Jamison 1990).
  • FIG 1 illustrates a robust phenomenon, called prepulse inhibition (PPI).
  • PPI prepulse inhibition
  • PPI is considered to be a measure of sensorimotor gating. It has demonstrated that PPI is disrupted in certain neuropsychiatry disorders that are characterized by an inability to filter or "gate" sensory (and, theoretically, cognitive) information, such as schizophrenia.
  • Perry et al. (2001a) reports that manic BD patients exhibit robust deficits in PPI, and that similar deficits are evident in DAT knockout mice (Ralph et al 2001a).
  • Hyperactivity in BD Increased motor activity is a cardinal feature of a manic episode, described in the DSM-IV as an "increase in goal-directed activity ... or psychomotor agitation".
  • Manic patients often report that they have more energy than usual and are observed to be physically restless, fidgeting, and changing posture and position frequently.
  • Medications used to treat mania such as lithium, divalproex sodium, and atypical antipsychotics significantly decrease motor hyperactivity in mania (Berk et al 1999; Bowden 2000; Swann et al 2002).
  • few studies have elaborated on the underlying neural mechanisms that mediate the hyperactivity of mania. Consistent with the central role of DA transmission in the expression of mania, it has been shown repeatedly that DA agonists induce hyperactive states and are therefore considered a model for mania (Lyon 1991).
  • rBPM rat Behavioral Pattern Monitor
  • Perseverative behavior refers to repetitive and potentially maladaptive sequences of behavioral responses (Crider 1997). Patients who have excessive perseverative behavior have a reduction in their observed response repertoire because the repetitious behavior occurs with increased probability, without the formerly appropriate stimulus present. The perseverative activity intrudes into the formation and/or the execution of the ongoing behavior and may be inappropriate to the current context and thus is different from "goal directed and intentional forms of repetition"
  • Perseverative activity can extend from the execution of simple responses to complex problem-solving behaviors and can manifest as motor behaviors or as a "persistent repetition of words, ideas, or subjects so that, once a patient begins a particular subject or uses a particular word, he continually returns to it in the process of speaking" (Andreasen 1979, p. 1320). Thus, the degree of perseverative activity varies depending upon the specific task (Freeman & Gathercole 1966). 10015] Perseverations are a hallmark feature of patients with frontal-cortex pathology (Goldberg & Costa 1986; Luria 1980; Milner 1963; Stuss & Benson 1984).
  • Antimanic medications such as lithium and divalproex sodium reduce manic symptoms in BD patients within three (McElroy et al 1996) to seven (Bowden et al 1997; Vasudev et al 2000) days of treatment initiation.
  • antimanic to refer to the class of agents represented by lithium and anticonvulsants such as divalproex sodium.
  • divalproex sodium reduces hyperactivity, racing thoughts, and other key symptoms of mania within days of treatment (Motohashi 1999; Token & Grundy 1999).
  • animal studies have shown that both typical and atypical antipsychotic agents attenuate inhibitory failures as measured by PPI.
  • the antimanic property of these medications may also be due to the fact that they attenuate inhibitory deficits in humans.
  • the present invention provides a translational approach to develop an explicit human analog of all rodent behavioral test paradigms, exploratory motor activity in a novel environment, i.e., the "open Field" test.
  • the present invention further provides that the analyses taken from the paradigm yield information about how a person responds to novelty and problem solving.
  • the human paradigm namely, human behavioral pattern monitor (hBPM), of the present invention provides an ability to directly compare findings from rodent models of a psychiatric disease with those obtained from psychiatrically ill human subjects.
  • the human paradigm, e.g., hBPM, of the present invention can further be used for neuropsychiatric analyses, drug efficacy measurement, new drug evaluation, and assessment of cognition on medications and/or in a real world problem solving environment.
  • the present invention provides a hBPM that mimics the rodent open field as closely as possible.
  • human subjects are told they will see a study coordinator in a short period of time, and are directed into a novel room.
  • the room is 10 by 13 feet and equipped with ten exploratory objects and one table, two open book shelves on opposing walls, a cabinet, and no chairs.
  • the exploratory objects are: 1. feather mask, 2. stuffed doll, 3. slinky, 4. yo-yo, 5. small sculpture, 6. musical instrument, 7. kaleidoscope, 8. soft toy, 9. balls, 10. toy animals.
  • the objects are evenly dispersed in the room on the shelves, table, and on top of the cabinet.
  • All ten objects are selected because they are uncommon, colorful and interactive and represent a variety of shapes, colors and textures and invite close visual and tactile inspection.
  • subjects are asked to enter into the room and wait for the examiner. The subject is instructed to make his/her self comfortable. No additional instructions are provided.
  • An examiner is stationed outside the door of the room to redirect the subject if they open the door or have questions. At the end of the 15-minute period, the experimenter directs the subject back to the laboratory.
  • the present invention provides two sources of data in the hBPM
  • the subject wears an ambulatory monitoring device that continuously collects movement data with the use of an accelerometer.
  • the room is also equipped with a hidden digital camera that captures the spatial location of the subject's position, in the form of x and y coordinates at a high sampling rate.
  • the present invention provides that the accelerometry data and the spatial location data are subjected to further novel non-liner dynamic analyses.
  • the present invention provides human subjects that run through the "open field" test paradigm, and physiologic and spatial location data are collected.
  • the present invention provides a translational approach and method to utilize the measures characterizing rodent locomotor behavior for application in human locomotor behavior. More specifically, the present invention provides methods to measure the locomotor behavior symptom in humans quantitatively. Locomotor hyperactivity is a commonly measured behavior in rodents and is used to quantify effects of new drug candidates. It is known that hyperactivity is a common characteristic of bipolar disease in humans.
  • the present invention provides two main measures to quantify human locomotor behavior: overall levels of activity as measured by 3-dimensional acceleration and dynamical entropy, defined as the degree of predictability of sequences of human accelerations. These measures are used to define different types of behavior of human exploring a novel environment. Furthermore, the present invention provides classification procedures of using measures that quantify acceleration and sequences of movements to classify them into different patterns of behavior (sitting, standing, walking etc.).
  • the present invention provides that the levels of locomotor activity are not correlated with predictability of locomotor activity, a result that replicates a similar finding in animals
  • the present invention provides that unique combinations of locomotor activity levels and predictability of locomotor sequences characterize different behaviors. Therefore, the present invention provides a first approach to quantify human behavior similar to methods used to quantify animal locomotor behavior. By using similar measures, the present invention further provides a translational model of drug actions such as antimanic agents, which can be used for future drug development.
  • the present invention provides studies of Bipolar Disorder (BD) and/or bipolar mania in both clinical human populations and related animal models.
  • the present invention also provides the use of human measures of motor activity and perseverative patterns in a manner that is parallel the corresponding measures of dopaminergic activation in pharmacologic and genetic animal models.
  • the present invention further provides studies of both antimanic and atypical antipsychotic treatments in animal models, using measures of PPI of startle, locomotor hyperactivity, and perseverative patterns of exploratory behavior. The evaluation of the effects of pharmacologic treatment modalities using parallel experimental measures in manic BD patients, on hospital admission and during treatment, will enable firm assessments of the predictive validity of potential animal models.
  • Figure 2 shows a photograph illustrating the layout of the open field, as well as an example of how a human subject is spatially tracked.
  • Figure 3 shows a diagram illustrating the translate information that can be gained from basic experimental models of hyperdopaminergia, e.g. acute amphetamine administration and DAT knockdown or knockout mice, as it relates to mania.
  • Figure 4 indicates that BD patients with psychotic mania, tested within 96 hours of acute psychiatric hospitalization, had significant deficits in PPI that were comparable to those of acutely hospitalized schizophrenia patients.
  • Figure 5 illustrates the acceleration data and the local dynamical entropy calculated.
  • Figure 6 illustrates that entropy differentiates perseverative from non- perseverative movements.
  • FIG. 7 shows that two atypical antipsychotics: clozapine (3 mg/kg) and quetiapine (2.5 mg/kg) reduce the PPI deficit in male DAT KO mice.
  • Figure 8 shows that an acute administration of fluoxetine (15 mg/kg) unmasks a deficit in PPl in -/- DAT KD that otherwise exhibited normal PPl.
  • Figures 9A and 9B show that 2 mEq/kg LiCI reduced the PPI-disruptive effects of 10 mg/kg amphetamine in both 129 (A) and C57(B) mice.
  • Figure 10 illustrates measures of sequential organization of behavior, i.e. the geometrical patterns of movements and the predictability of movement sequences, and levels of locomotor activity in vehicle-treated C57BL/6J, 129S6, and 129X1 mice.
  • Figure 11 provides a graphical example of activity data using the LifeShirt®.
  • Figure 12 illustrates specific areas in the mBPM. There are 4 areas defined per enclosure: (1) 4 corner areas (dark gray), (2) 2 short-wall and (3) 2 long-wall areas (gray), and (4) the center (white). Locations of the holes are indicated by circle. An entry into a new area is counted as the basic measure of locomotion.
  • Figure 13 illustrates stimulant effects on rat locomotor patterns in the Behavioral Pattern Monitor.
  • a) The rat treated with saline explored little of the environment, making two or three excursions around the chamber, exhibiting short meandering movement in one or two areas then moving on.
  • the rat also exhibited more than one area of focused activity ['home corner' (Geyer 1982) or 'home base' (Eilam and Golani 1989)].
  • the phencyclidine-treated rat exhibited sweeping movement patterns, from one corner to another, often circling from a home base that covered the right side of the chamber, with repetitive movements,
  • the scopolamine- treated rat displayed increased long and straight movements particularly close to the chamber walls, deviating very little from this path. The level of activity was as great as amphetamine but with scopolamine the rat did not spend time focusing on any areas in particular, nor did it cross the center very often, displaying very repetitive movements. Data are provided for measures of locomotor activity (transitions), locomotor pattern (spatial d) and exploration (holepokes).
  • Figure 14 illustrates effects of amphetamine on mouse locomotor patterns in the Behavioral Pattern Monitor.
  • the effects of saline (a) and amphetamine (b) on the behavioral organization of a representative mouse are presented, a) Mice treated with saline exhibit exploration throughout the chamber, but only perform a limited number of excursions around the chamber. This animal spent most of the time in the bottom right hand side of the chamber (the "home corner"), b) Mice treated with amphetamine however, exhibit a large number of excursions around the chamber, covering the chamber floor many times in a variety of paths. They also display several areas where their behavior is concentrated, suggesting several home bases as opposed to the one home corner observed in the saline administered mouse.
  • While the x-y plots represented here are genuine movements, they also reflect a limitation of the number of photobeams used to identify a subject's position. Data are also provided for measures of locomotor activity (transitions), locomotor pattern (spatial d), and exploration (holepokes). Mice treated with amphetamine display a hyperactive phenotype, with lower spatial d and lower exploratory behavior when compared to control animals.
  • J0039J Figure 15 illustrates locomotor patterns of dopamine transporter knockdown and wild type littermate mice in the Behavioral Pattern Monitor.
  • Representative locomotor patterns of dopamine transporter wildtype (WT; a) and knockdown (KD; b) mice are shown, a) WT mice spend most of their time near the chamber walls and while some movement is made to explore the center, activity is concentrated in the left wall, where the mouse circles back and forth, b) In contrast to the time spent in the home corner by the WT mouse, this KD mouse displayed numerous areas of interest and exhibited more varied paths of activity.
  • Locomotor activity transitions
  • pattern spatial d
  • exploration holepokes
  • Figure 16 illustrates effects of the selective dopamine transporter uptake inhibitor GBR 12909 on mouse locomotor patterns in the Behavioral Pattern Monitor.
  • the representative locomotor patterns are shown for mice treated with saline (a) or GBR 12909 (b).
  • a) Mice treated with saline display very limited activity, making only one or two excursions around the chamber with limited exploration into the center of the chamber, b) Mice treated with GBR 12909 display far greater levels of activity, with numerous areas of focused activity and greater variety of paths taken.
  • mice treated with GBR 12909 displaying hyperactivity, increased exploratory behavior, and straighter line movements (lower spatial d) than mice treated with saline.
  • Figure 17 illustrates patterns of human subjects in the human Behavioral Pattern Monitor.
  • the layout of the room as observed through a fisheye lens is outlined in red.
  • the locomotor pattern of a representative healthy subject (a), or manic BD (b) and schizophrenia (c) patients are shown in black.
  • the location of the subject's upper torso (specifically, the LifeShirt® vest) in x- and y-coordinates was recorded by tracking software (Clever Systems, Inc) as the subject examined the room and the objects located therein.
  • An accelerometer embedded in a wearable ambulatory monitoring device also recorded levels of motor activity in digital units for each subject, a) The healthy comparison subject walked around the room once, investigated the window, which is covered, examined some objects placed on the bookshelves farthest from the door, and finally moved to the desk, spending the remainder of time examining that area and the objects found there, b) The manic BD patient conducted numerous excursions around the room, often concentrating movement at specific locations such as the window and bookshelves farthest from the door and the small filing cabinet. Apart from the obvious quantity of movements that differentiate this subject from the healthy comparison subject, the manic BD subject also clearly failed to exhibit a preference for one location, spending time in numerous areas.
  • FIG. 18 illustrates an observed walking and entropy-derived probability.
  • the entropy-derived probability of walking corresponded exactly to the observed walking at each time-frame.
  • Figure 19 illustrates the "open field” studies with Bipolar Mania and ADHD patients and sequences of (x, y) analyses.
  • FIG. 21 illustrates an increased motor activity and straighter movement patterns of Bipolar Mania subjects.
  • 100461 Figure 22 illustrates a pattern of a time spent in the "open filed" in Bipolar Mania, ADHD and normal comparison subjects. Left (a) illustrates that Bipolar Mania subjects spent more time in the center of the room; Right (b) illustrates that normal and ADHD individuals spent more time along the short wall in the room. 100471 Figure 23 shows example patterns of comparison subject (a), Bipolar Manic subject (b), and ADHD subject (c) in the "open field”.
  • Figure 24 illustrates the Human Behavioral Pattern Monitor (hBPM), a novel room furnished with ten engaging stimuli and no chairs. Subjects are directed inside with no instruction except to wait for the experimenter.
  • hBPM Human Behavioral Pattern Monitor
  • Figure 25 illustrates a use of hBPM for measuring behavioral patterns for Manic Bipolar Disorder (BD) and Schizophrenia (SCZ) patients.
  • A denotes how many times the subjects interacted with any object;
  • B gives the amount of time the subjects were walking (in seconds); and
  • C gives the quantity of time spent with all objects.
  • * Denotes p ⁇ 0.05 when compared to normal comparison (NC) subjects,
  • # Denotes p ⁇ 0.05 when compared to SCZ patients.
  • Figure 26 illustrates the LifeShirt®-Clinical System (VivoMetrics, 2002), a wearable ambulatory monitoring device that records physiologic functions. Motor activity is quantified with a centrally mounted accelerometer embedded in the device.
  • Figure 27 illustrates motor activity in session one for manic BD patients, SCZ patients, and NC subjects.
  • manic BD > nonpatients, p ⁇ 0.01 ;
  • manic BD > schizophrenia, p O.01 ;
  • manic BD > schizophrenia, p ⁇ 0.05.
  • Figure 28 illustrates motor activity across all three sessions for manic BD patients and NC subjects. ** manic BD > nonpatients, p ⁇ 0.01 .
  • the present invention provides a behavioral pattern monitor for neuropsychiatric analyses, drug efficacy measurement, new drug evaluation, or assessment of cognition on medications, comprising a test subject locomotor space, means for recording information about test subject's locomotor information within the space, and information relating at least one control subject to a locomotor pattern for comparative neuropsychiatric analyses, drug efficacy measurement, new drug evaluation, or assessment of cognition on mediations.
  • the behavioral pattern monitor is specific to rodent behavior and may be used for validating animal models of psychiatric diseases.
  • the present invention also provides that the behavioral pattern monitor can be specific to human behavior.
  • the space is a room furnished with a plurality of engaging stimuli
  • said means for recording information about the test subject's locomotor information is an overhead video camera.
  • the human subject's locomotor information comprises the number of interactions with said stimuli, the time spent in locomotion, the time spent interacting with each stimulus, and the pattern of interacting with each stimulus.
  • the pattern of interacting includes distance pattern of activity, geometric or spatial pattern of activity, and time spent in different parts of the room.
  • the engaging stimuli comprises exploratory objects selected from a mask, a doll, a toy, a sculpture, a musical instrument, a kaleidoscope, a ball, a stuffed animal, and combinations thereof.
  • the present invention provides a model that can be used to diagnose or assess a patient having bipolar disorder-manic episode, schizophrenia, Attention Deficit Hyperactivity Disorder, or other neuropsychiatric disorders.
  • the locomotor information can comprise measuring locomotor behavior to characterize hyperactivity, differentiate diagnostic groups, or study habituation.
  • the present invention provides a method of determining a behavioral pattern of a human subject comprising: a) providing a behavioral pattern monitor for neuropsychiatric analyses, drug efficacy measurement, new drug evaluation, or assessment of cognition on medications, comprising a room for test subject locomotor space, a means for recording test subject locomotion while within the space, and information relating at least one control subject to a locomotor pattern for comparative neuropsychiatric analyses, drug efficacy measurement, new drug evaluation, or assessment of cognition on medication said behavioral pattern monitor; b) guiding said human subject inside said room, c) recording information about said human subject's locomotor behavior for at least 15 minutes, and d) comparing information about human subject's locomotor pattern to the information relating at least one control subject to determine the human subject's relative behavioral pattern.
  • the method provides that the space is a room furnished with a plurality of engaging stimuli, and said means for recording information about test subject's locomotor information is an overhead video camera.
  • the human subject's locomotor information comprises the number of interactions with said stimuli, the time spent in locomotion, the time spent interacting with each stimuli, and the pattern of interacting with each stimuli.
  • the pattern of interacting includes distance pattern of activity, geometric or spatial pattern of activity, and time spent in different parts of the room.
  • the engaging stimuli comprises exploratory objects selected from a mask, a doll, a toy, a sculpture, a musical instrument, a kaleidoscope, a ball, a stuffed animal, and combinations thereof.
  • the present invention provides a method that can be used to diagnose or assess a patient having mania bipolar disorder, schizophrenia, Attention Deficit Hyperactivity Disorder, or other neuropsychiatric disorders.
  • the locomotor information can comprise measuring locomotor behavior to characterize hyperactivity, differentiate diagnostic groups, or study habituation.
  • Mania is the defining feature of BD, a highly recurrent and severe psychiatric disorder.
  • DAT dopamine transporter
  • the manic state may involve a dysregulation of dopaminergic systems. These systems are critical for the control of inhibitory functions.
  • antimanic agents which may "normalize" cortical and subcortical hyperactivity also modulate directly or indirectly the dopaminergic system. Nevertheless, there is a striking paucity of preclinical models related to BD, which has hindered examination of neural circuit abnormalities contributing to BD.
  • the present invention provides translational research involving cross-species measures that reflect abnormalities in dopaminergic systems to further the understanding of BD. Specifically, the present invention provides parallel studies of inhibitory deficits in manic BD patients and in mice in which the dopamine (DA) transporter (DAT) has been manipulated either pharmacologically (i.e. amphetamine) or genetically (i.e. DAT knockdown and knockout mice).
  • DA dopamine
  • DAT dopamine transporter
  • the unifying construct is inhibition, which cannot be characterized adequately by any one measure. Therefore, the present invention assesses inhibitory deficits in three domains; 1. sensorimotor inhibition, i.e. stimulus-induced attenuation of motor action, is assessed using prepulse inhibition (PPI) of the startle response; 2. motor hyperactivity, i.e. inability to inhibit ongoing actions, upon exposure to a relatively novel environment is assessed by species-appropriate ambulatory monitoring devices that characterize motor activity with a high degree of spatial and temporal resolution; and 3. perseveration, i.e. an inability to inhibit prepotent or ongoing responses that results in a decline in behavioral variety, is measured in humans and mice using non-linear analyses of spatial and temporal patterns of motor responses.
  • PPI prepulse inhibition
  • the invention's central construct is hyperdopaminergia, i.e. the increased availability of DA as a modulatory transmitter in prefrontal cortex and subcortical areas, possibly related to the observed genetic association between BD and DAT.
  • the present invention provides two established treatments: (1) the direct modulation of the hyperdopaminergic state via DA D2 receptor antagonism as represented by atypical antipsychotic agents, and (2) indirect modulation of this state via antimanic agents such as lithium and valproate.
  • the present invention combines these pharmacological manipulations in both manic BD patients and the animal models of hyperdopaminergia with behavioral measures that are closely matched across species to elucidate the pathways that underlie mania.
  • One of the objects of the present invention is to develop and validate parallel animal and human models as predictive tools for evaluating new treatment interventions in bipolar mania and to identify key target variables, i.e. prepulse inhibition, hyperactivity, perseveration, which can be used to track treatment efficacy.
  • the present invention provides a test model that mania is highly associated with impaired inhibitory functioning and that impaired inhibitory functioning is associated with hyperdopaminergic states.
  • Manic BD patients are assessed on three inhibitory measures during highly symptomatic and remitted states.
  • the present invention further provides an assessment performance on the three inhibitory measures in patients treated with medications that are direct DA antagonists versus medications that affect DA transmission indirectly.
  • the present invention provides an explicit human analog of the most classic of all rodent behavioral test paradigms, exploratory motor activity in a novel environment, i.e. the "open field" test, namely, Human Behavioral Pattern Monitor (hBPM).
  • the present invention provides an assessment of the inhibitory functioning of manic BD patients using the hBPM.
  • the present invention further provides that manic BD patients exhibit significantly greater deficits on measures of inhibition (less PPl, more hyperactivity, and more perseveration) than normal comparison (NC) subjects.
  • the present invention also provides an assessment of the relationship between inhibitory functioning and manic symptoms in BD patients using the hBPM.
  • manic BD patients are tested at three intervals: 1) within 72 hours (Session 1) of acute hospitalization; 2) 7 days later (Session 2); and 3) 28 days after Session 1 (Session 3).
  • the present invention provides that manic BD patients show improvement in inhibitory function (increased PPI, decreased hyperactivity, and decreased perseveration) across the three test sessions compared to the NC subjects.
  • the present invention further provides that, in manic BD patients, decreased inhibitory deficits is related to decreased symptoms as measured by Young Mania Rating Scale Scores over the three test sessions.
  • the present invention provides a test to whether lithium, anticonvulsants, and atypical antipsychotic medications differentially improve inhibitory functioning.
  • the present invention provides that manic BD patients treated with atypical antipsychotic medication (alone or in combination with lithium or an anticonvulsant) demonstrate significantly greater rate of change (improvement) than patients treated with lithium or an anticonvulsant on measures of inhibitory function (increased PPL, decreased hyperactivity, and less perseveration) over the 3 test sessions.
  • the present invention further provides that, at Session 3, manic BD patients treated with an atypical antipsychotic, lithium, or an anticonvulsant alone exhibit more inhibitory deficits than patients treated with a combination of an atypical antipsychotic and an antimanic medication.
  • the present invention further provides a potential validity of two mouse models related to the mania phenotype characteristic of bipolar disorder. Both of the models are based on the deficient PPI, locomotor hyperactivity, and perseverative patterns of activity associated with increases in synaptic DA produced by: (1) acute dopaminergic activation produced by the administration of amphetamine; or (2) chronic dopaminergic activation in the DAT-deficient mice. For each of the models, validity is assessed specifically by assessing the ability of the model to detect the effects of drug regimens used in the treatment of mania and/or bipolar disorders (e.g. acute and chronic valproate or lithium, and acute atypical antipsychotics).
  • drug regimens used in the treatment of mania and/or bipolar disorders e.g. acute and chronic valproate or lithium, and acute atypical antipsychotics.
  • the present invention provide an assessment of the ability of antimanic drug treatments to prevent the disruptions in three domains of behavioral inhibition produced by acute hyperdopaminergia (amphetamine) using the mouse model.
  • the present invention provides that acute and/or subchronic treatments of lithium, valproate, and atypical antipsychotic medications prevent the amphetamine- induced decreases in PPI, increases in motor activity, and increases in perseverative locomotion in the mouse model.
  • the present invention provides an assessment of the ability of antimanic treatments to reverse the disruptions in three domains of behavioral inhibition produced by chronic hyperdopaminergia in DAT- deficient mice.
  • the present invention provides that subchronic treatment with antimanic and atypical antipsychotic medications reverses the reductions in PPI (DAT - /- KO), increases in motor activity, and increases in perseverative locomotion in DAT- deficient (DAT -/- KO and DAT -/- KD) mice.
  • Acute pharmacological treatments also reverses some of the less dramatic phenotypes in DAT-deficient mice.
  • the present invention provides an assessment of the ability of antidepressant treatments to precipitate mania-like disruptions in behavioral inhibition in DAT +/- knockout or DAT knockdown mice.
  • the present invention provides that subchronic (and acute) treatment with antidepressant medications induces disruptions in the three domains of inhibition DAT- deficient mice that exhibit minimal or no phenotypic abnormalities at baseline (DAT +/- KO and, for PPI, DAT -/- KD) mice.
  • the present invention further provides a translational integration in implementing PPI as a cross-species paradigm of inhibition to the study of BD.
  • the present invention provides a similar cross-fertilization of paradigms involving motor activity that have been developed extensively in rodents and are applied to innovative studies in humans.
  • the present invention provides the use of the LifeShirt® in a novel paradigm to assess motor activity and perseverative patterns of behavior in SD patients.
  • the present invention provides that the combination of inhibitory deficits (altered PPI, hyperactivity, and perseveration) are a composite endophenotype that is unique to BD patients and can be used to assemble and validate animal models of mania in BD.
  • the present invention fills this gap by generating longitudinal profiles of inhibitory dysfunctions in highly symptomatic manic BD patients, using measures derived from animal paradigms. These profiles can be used in animal studies to explore a prominent neurotransmitter target implicated in mania, namely hyperdopaminergia.
  • the present invention can help to identify endophenotypic markers of BD that could aid in future studies of the genetics of this disorder.
  • the present invention further provides that using an operational measure of sensorimotor inhibition offers an innovative approach to studying BD because: 1) there are existing models for understanding the neural substrates of central gating processes; 2) impaired sensorimotor inhibition has been shown to be associated with, and perhaps causally related to, disturbances in thinking, while normal gating is thought to be relevant to adaptive functioning; and 3) PPI is also reliably measured in rodent populations, making it an excellent tool for translational research.
  • the present invention yet provides that antimanic treatments attenuate motor hyperactivity by either direct or indirect influences on DA neurotransmission.
  • the present invention further provides a mouse behavioraJ pattern monitor (mBPM) completely analogous to the rat behavioral pattern monitor (rBPM).
  • mBPM mouse behavioraJ pattern monitor
  • the mBPM system confirms that sequences of locomotor behavior are not randomly associated events but comprise highly organized sequences of behavior. The organization of these sequences is complex because unconditioned locomotor behavior is contingent on many factors.
  • measures of different concepts such as novelty seeking, approach-avoidance, exploration, establishing a home base, and habituation
  • a set of measures quantifying the sequential organization of behavior is developed. This approach is based on the general concept that the sequential characteristics of behavior, i.e.
  • the present invention further provides that both amphetamine-treated and DAT KO mice show an abnormal sequential pattern of locomotor activity that is characterized by rapid running around the perimeter of the test chamber. This form of hyperactivity is referred as being "perseverative" because the same pattern of movement is repeated again and again.
  • the degree to which animals exhibit such straight-path patterns of locomotion is quantified using the non-linear measures of sequential patterns that was developed originally using data from the rat BPM.
  • the present invention provides that a measure of dimensionality derived from fractal geometry - spatial d - which was first developed for studies in rats (Paulus & Geyer 1991) and subsequently extended to studies of mice and humans, is dramatically altered in DAT KO and KD mice.
  • the present invention provides that drugs or genetic factors - independent of differences in the amount of locomotor activity - alter spatial d. That is, the pattern of the behavior is orthogonal to the amount of the behavior.
  • This "perseverative" locomotor activity may reflect a failure of motor inhibition, insofar as it results when an animal fails to pause when encountering a corner or other object in the environment, as rodents normally do. Indeed, if another animal is in the same chamber, a DAT KO mouse simply runs or jumps over it rather than exhibits the normal social interactions characteristic of such an encounter between mice. Thus, it appears that DAT KO mice, like mice treated with amphetamine, cannot inhibit their motor activity in a normal manner.
  • the present invention provides rodent and human behavioral pattern monitors, e.g., rBPM, mBPM, and hBPM), and use of these BPMs thereof.
  • the present invention provides rodent and human studies in the BPM, providing a reverse-translational approach to Bipolar disorder, and other psychological disorders.
  • the present invention provides that hBPM differentiates activity patterns of BD and ADH subjects.
  • the present invention provides hBPM differentiates patients with acute psychotic Mania from Schizophrenia.
  • the present invention provides that hBPM can be used to quantification of motor hyperactivity in Mania.
  • Amphetamine Disrupts Prepulse Inhibition in Mice Several studies were published for demonstrating that amphetamine disrupts PPI in mice, as those had been shown previously in rats (Geyer et al 2001; Mansbach et al 1988). The first report of this effect of amphetamine was published in 1996 (Dulawa & Geyer 1996) and such effect is subsequently reversed by pretreatment with the D2-like DA antagonist raclopride (Brody et al 20113a).
  • mice Using genetically modified mice, it was shown that the PPI-disruptive effects of amphetamine were maintained in mice lacking Dl, D3, or D4 DA receptors, but were absent in mice lacking the D2 subtype of DA receptors (Ralph et al 1999; Ralph-Williams et al., 2003a).
  • DAT dopamine transporter
  • a DAT "knockout" (KO) mouse has been created that completely lacks the gene coding for the DAT (Giros et al 1996). It was found that the DAT KO mice exhibit marked deficits in PPI of startle and (Ralph et al., 2001 ) in addition to the profound locomotor hyperactivity seen in these mice.
  • the DAT Knockdown Mouse Although the full DAT KO mice exhibit a chronic hyperdopaminergic tone, they also have profound physiological alterations
  • mice have chronic hyperdopaminergia (e.g., a 70% increase in extracellular striatal DA), but they do not show gross physical changes. Behaviorally, the DAT KD mice are hyperactive in a novel open field and show impaired response inhibition in a number of paradigms (Zhuang et al 2001). Thus, the DAT KD mutant mice may prove useful as an animal model for the manic state associated with BD.
  • the +/- DAT KO mice appear to be normal, while the -/- DAT KD mice are clearly hyperactive.
  • the possibility that DAT- deficient mice may be useful as a model of vulnerability to mania was tested, by examining the ability of antidepressant medications to precipitate a deficit in PPI or increases in motor activity and perseveration only in the +/- DAT KO or the -/- DAT KD mice and not in wildtype mice.
  • Non-linear Measures of Perseveration in Mice Based on the extensive experience pioneering the use of non-linear measures to characterize sequential patterns of movements in rodents, and perseverative patterns in particular, and as detailed in the article (Pauius et al., 1999), this work was extended from rats to mice using a Video- tracking system to monitor unconditioned locomotor behavior in a novel environment.
  • Figure 10 illustrates the patterns obtained. The movement patterns were analyzed analogously to the scaling pattern that was advanced previously based on studies of rats (Pauius & Geyer 1991) and which was derived from similar observations in physical and mathematical systems (Mandelbrot 1982).
  • sequences of movements observed with varying spatio-temporal resolutions may not yield a simple linear relationship between the (measured) distance traveled and the observational resolution
  • the resolution is determined by the number of micro-events that are considered for the calculation of the distance traveled. For example, straight movements along a wall of the enclosure or traversing the center are characterized by the fact that the distance traveled doubles if the number of micro- events used to calculate the distance is doubled. Therefore, there is a linear relationship between the number of micro-events and the distance traveled. However, meandering or circumscribed movements are not characterized by this simple linear relationship.
  • the spatial scaling exponent, d quantifies the relationship between the number of micro-events, k, used to calculate the distance, L, and the change in resolution.
  • the average spatial scaling exponent, d typically varies between 1 and 2 for straight and highly circumscribed movements, respectively
  • the dynamical entropy measure, h is described in detail in the publication. Briefly, this measure quantifies the degree of uncertainty of predicting the next movement based on the sequence of preceding movements and is based on similar measures assessing the emergence of uncertainty in nonlinear dynamical systems (Eckmann & Ruelle 1985). [00901 The dynamical entropy is expressed in bits/step and is related directly to the number of different movement possibilities per step. Thus, the more different paths are observed, the larger the value of h (see Fig 3 in Paulus et al 1999). The dynamical entropy approaches zero if the animal exhibits a highly repetitive path pattern.
  • Amphetamine-induced Hyperactivity in Mice The behavioral profile induced by acute administration of amphetamine in different strains of mice was established. As in rats, amphetamine increased levels of locomotor activity and the altered the patterns of locomotor movements. Furthermore, the effects of different doses of amphetamine differed significantly across strains. These results underscore the important contributions of genetic factors to the behavioral profile induced by stimulants.
  • mice Different strains of mice were used to determine whether measures of sequential organization of behavior, i.e. the geometrical patterns of movements and the predictability of movement sequences, are independent of levels of locomotor activity. It was confirmed that robust strain differenced in motor phenotypes in the vehicle- treated C57BL/6J, 129S6, and 129X1 mice (Ralph et al., 2001b). C57BL/6J mice continued to explore the enclosure during the entire test session. The 129X1 mice initially explored the enclosure, briefly moving into the center, while the 129S6 mice sampled only a small area of the test environment, rarely entering the center.
  • DAT KD mice exhibited more perseverative patterns of locomotor behavior than did the WT controls. Specifically, DAT KD mice exhibited significantly straighter sequences of motor patterns (lower spatial d values). When the DAT KD mice were treated with 100 mg/kg valproate, a dose which had no effect to WT mice, their hyperactivity was reduced significantly. Furthermore, while drug treatment had no effect on spatial d in the +/+ mice, valproate attenuated the perseverative patterns of motor behavior (diminished the predominance of straight sequences of locomotor activity as evidenced by increased spatial d) seen in the DAT mice.
  • looioo The potential validity of two mouse models related to the mania phenotype characteristic of BD were evaluated. Both of the models are based on the deficient PPI, motor hyperactivity, and perseverative patterns of locomotion associated with increases in synaptic DA produced by: (1) acute dopaminergic activation produced by amphetamine; or (2) chronic dopaminergic activation in the DAT deficient mice. The ability of the two models were assessed to detect the effects of drug regimens used in the treatment of mania in BD patients (e.g. acute and chronic valproate, lithium, and acute atypical antipsychotics).
  • drug regimens used in the treatment of mania in BD patients e.g. acute and chronic valproate, lithium, and acute atypical antipsychotics.
  • C57BL/6 Mice The C57BL/6 mice were selected after consideration of a number of complex factors. However other inbred as well as out-bred strains of mice may well be warranted. The C57BL/6 mouse is the most extensively studied largely because it is the most common background strain on which gene knockouts are developed. Congenic lines (i.e. back-crossed at least 10 generations) of DA Dl, D2, D3, and D4 receptor KO mice were established, and DAT KO are on a mixed C57/129 background that most closely resembles C57s in its behavioral profile. Studies of PPI at baseline and after treatments with amphetamine or NMDA antagonists in all these DA-related KO mice on the C57 background were successfully done (see cited papers). Hence, the dose regimens and experimental parameters appropriate for the proposed studies were known.
  • the DAT KD -/- mice are, of course, hyperactive. Also, C57 mice treated with amphetamine exhibit dose-related increases in motor activity and perseverative locomotion, while 129-related strains show less reliable effects of amphetamine.
  • the pharmacological studies of the effects of amphetamine as a model of acute hyperdopaminergia include both sexes in order to optimize doses of amphetamine for the appropriate behavioral effects and to enable more complete comparisons with the parallel studies of DAT-deficient mice as a model of chronic hyperdopaminergia.
  • mice were allowed at least a 5-day period for acclimation to the animal room before behavioral testing and are handled every day.
  • Food Hard Teklad, Madison, WI
  • water were freely available throughout the experiments, except during behavioral testing.
  • Genotyping of both DAT KD and DAT KO mice consisted of the phenol-chloroform extraction method and PCR cycling methodology as published by the originators of the mice (Giros et al., 1996; Zhuang et al., 2001).
  • One (1) cm tail lengths were obtained from each mouse at weaning and digested in proteinase K and buffer. Phenol-chloroform extraction were used to obtain DNA from each mouse.
  • PCR were perform using Amersham PCR beads and 3 primers (1 volume of primer for the WT DNA, 1 volume for the mutant DNA, and 2 volumes of primer common to both strands). PCR analysis were analyzed on polyacrylamide gels.
  • Drugs Injected drugs were delivered s.c. or i.p. at a volume of 5 ml/kg. Drugs were dissolved in isotonic saline o other appropriate vehicle just prior to use.
  • Vibrations of the Plexiglas cylinder caused by the whole-body startle response of the mouse were transduced into analog signals by a piezoelectric unit attached to the platform, digitized, and stored. Sound levels referred to the A weighting scale (SPL) and were measured as previously described (Geyer & Swerdlow, 1998). The multiple chambers were calibrated weekly using a dynamic calibration system to ensure equivalent and consistent sensitivities.
  • SPL A weighting scale
  • mice utilized the VideoTracker system, the present studies use the more powerful mBPM, which monitors additional behaviors and enables testing in the dark.
  • the mBPM system includes ten chambers, each enclosed within a ventilated external box.
  • a well-developed software used for the rat BPM system (Geyer et al 1986)was adapted to accommodate the increased number of photobeams used for the mBPM. The system was housed in a dedicated and sound-attenuated room.
  • Each chamber consists of a 30.5 x 61 cm x 38 cm Plexiglas hole board that is equipped with 3 floor holes in the front, middle, and rear part of the floor and 8 wall holes (3 along either side of the long walls, and two holes in the front and back walls).
  • the location of the mouse was obtained from a grid of 12 x 24 photobeams 1 cm above the floor (height is adjustable).
  • Each hole is also equipped with a photobeam. Rearing is detected by an array of 16 photobeams placed 2.5 cm above the floor an, aligned with the long axis of the chamber. The status of the photobeams is transmitted with a frequency of 18 Hz to a PC-compatible computer.
  • mice were determined based on estimated effect sizes and power calculations using a full factorial ANOVA model with ⁇ >0.8 and ⁇ 0.05. Previous studies using the primary measures have shown that, on average, 8-12 animals per group provide the projected power. The animals are brought to the laboratory 1 h before testing.
  • the primary measures include: total entries, duration of time in the center, rearings hole pokes, spatial d, and dynamical entropy h. When appropriate, additional measures include: number and durations of hole pokes, number of entries into the center, and duration of time in the comers.
  • ANOVA Analysis of Variance
  • mice Model Assess the Ability of Antimanic Treatments to Prevent the
  • Groups for each treatment condition typically contained 10 mice each, based on our extensive experience with the effects of amphetamine on these measures in C57BL/6J mice.
  • two doses of the pretreatment drug and one dose of amphetamine were used.
  • Amphetamine sulfate was administered intraperitoneal Iy (i.p.) at a dose of 7.5 mg/kg for male mice and 10 mg/kg for female mice (calculated as the salt), based on the prior dose-response studies in C57BL/6J mice (Brody et al 2003b; Dulawa & Geyer 1996; Ralph et al 2001b; Ralph et al 1999).
  • amphetamine was a within-subjects factor and pretreatment a between- subjects factor in a baselinematched, cross-over factorial design.
  • a typical experiment assessing the interaction between a pretreatment drug and amphetamine on PPI use 30 mice, 10 for each level of the pretreatment factor.
  • mice are tested in a brief baseline session that were used to create groups that were matched for both startle magnitude and level of PPI. Each mouse was then tested twice at an interval of one week after a fixed pretreatment and either vehicle or amphetamine in a counter-balanced order. The pretreatment were given at an appropriate time (typically 30-60 min) prior to testing and the vehicle or amphetamine treatment were given 10 min prior to testing (Brody et al., 2003). Thus, each mouse receives only one amphetamine treatment. Note that neither sensitization nor tolerance nor carryover effects of amphetamine were typically found in tests of PPI in rodents (Dirks et al 2001; Druhan et al., 1998).
  • the first treatment was an acute administration of sodium valproate, a sodium channel blocker, inhibitor of GABA transaminase, and inhibitor of phosphoinositol turnover (50 or 100 mg/kg, free base, i.p. 30 min pretest).
  • the 100 mg/kg dose of valproate was sufficient to reverse the locomotor hyperactivity phenotype in DAT -/- KD mice without affecting locomotor activity in the +/+ mice (Ralph-Williams et al 2003b). This dose has similarly been shown to block the effects of acute administrations of amphetamine on motor measures of distractibility in rats (Agmo et al 1997).
  • Chronic Valproate The studies were expanded with valproate by feeding animals food containing valproate, as developed by Dr. Husseini Manji at NIMH. With Dr. Manji's consultation, it was confirmed that the expected blood concentrations of valproate were achieved in the testing wild-type C57 mice.
  • the study of chronic valproate is important to better mimic the clinical use of the drug and to establish a more steady-state blood level of the drug prior to the amphetamine challenge.
  • the amphetamine results showed that 100 mg/kg valproate was not effective in 129SvPaslco mice and did not reverse the PPI deficit seen in DAT -/- KO mice (unpublished).
  • mice were placed on either the control or valproate diet for 9 days (as adjusted via pilot studies) prior to the first test session with either vehicle or 10 mg/kg amphetamine sulfate (dose to be adjusted based on Aim 4 studies).
  • amphetamine or vehicle One week later, mice were re-tested after the alternative treatment (amphetamine or vehicle). Blood levels of valproate were determined for each mouse during the week between tests using samples obtained from orbital eye-bleeds. 5-10 ul samples from mice were obtained. The valproate assays were conducted on a 3 ul sample. Blood levels of individual mice were used in additional regression analyses to assess the relationship between effective dose and behavioral effect.
  • amphetamine treatment is continued to be used as a categorical factor, but pretreatment condition is replaced by individual blood levels as a predictor variable.
  • J0117J Acute Lithium The designs of the acute and chronic lithium studies parallel those described for valproate. The data indicated that 85 mg/kg (2 mEq/kg) lithium chloride (LiCl) was effective in reducing the PPI-disruptive effects of 10 mg/kg amphetamine in male mice from both the S 129SvPasIco and C57BL/6J strains. This dose was based on the literature (Gould et al 2001) and confirmed to yield a serum lithium concentration that was within the therapeutic range (Goodwin & Geddes 2003). It was confirmed using doses of 1 and 2 mEq/kg i.p.
  • a pretreatment-by-treatment interaction in a 3X2 factorial ANOVA was provided in which pretreatment was a between subjects factor and treatment is a repeated measure.
  • Chronic Lithium Using a design similar to that described for chronic valproate, the effects of amphetamine on PPI in mice treated chronically with lithium in the food were also assessed. As described above for valproate, preliminary studies were conducted using different concentrations of LiCl in the food (as has been used successfully in rats) to identify concentrations that yield appropriate serum levels of lithium (0.5 mmol - 1.5 mmol). It is provided that 10 g LiCl per kg of food for 2 days followed by 20 g/kg were appropriate based on previous study of rats (Gould et al 2003). A dose of 1.5 mEq/kg administered s.c.
  • mice were treated with either vehicle or 10 mg/kg amphetamine sulfate. One week later, mice were retested after the alternative treatment (amphetamine or vehicle). Mice were then maintained on their specific diet and sacrificed without anesthesia within a few days of their last PPl test for trunk blood collection and serum lithium determinations.
  • the design is a counter-balanced order, factorial design with 3 levels of the pretreatment factor (diet; between subjects) and 2 levels of the treatment factor (amphetamine; within subjects).
  • the pretreatment by treatment interaction were the same as in the above studies.
  • regression analyses were also used, with the serum levels of individual mice serving as a predictor variable.
  • Antimanic compounds of interest may include, but not limited to: carbamazepine, olanzapine, or quetiapine.
  • Additional mood stabilizers may include, but not limited to: lamotrigine; topiramate; and gabapentin.
  • One of the most important of additional drugs would be acute and/or subchronic carbamazepine.
  • Carbamazepine is a tricyclic anticonvulsant drug used in the treatment of mania. Acutely, carbamazepine are administered at a dose of 50 mg/kg (to be confirmed in pilot dose- finding studies) and tested as in the prototypical experiment above (i.e. 2-by-3 design with amphetamine).
  • the subchronic treatment matches that used previously to block the induction of cFOS by 2 mg/kg methamphetamine, namely one week on a chow containing 0.25% carbamazepine and a second week on a 0.5% chow (Lee et al 2000). Pilot studies and blood assays are conducted to confirm the effectiveness of this regimen and its effects on motor activity by itself.
  • [01241 Acute Amphetamine Model, Motor Activity Based on the dose-dependent increases in locomotor activity and perseverative patterns seen in the C57BL/6J mice, the ability of antimanic agents to reverse these behaviors in mice was examined. In each case, treatment regimens that do not significantly reduce locomotor activity by themselves was utilized. As in the PPI experiments, studies of male and female mice were conducted separately using C57BL/6J mice adapted to the reversed light cycle for at least one week and handled repeatedly. Testing during the dark phase of the light cycle is extremely important for ethologically relevant studies of exploratory locomotor activity in rodents. Groups for each treatment condition typically contain 10 mice each, based on the extensive experience with the effects of amphetamine on locomotor activity in C57BL/6J mice.
  • Amphetamine sulfate were administered at a dose of 4.0 mg/kg for male mice and 5.0 mg/kg for female mice (calculated as the salt), based on the prior dose-response studies in C57BL/6J mice (Ralph et al 2001 b; Kadner, Geyer, in preparation). These doses produce robust locomotor activation and perseverative patterns without being close to the threshold for the focused stereotypies that can compete for expression with locomotor activity (Kadner, Masten, Geyer, in preparation).
  • amphetamine is a within-subjects factor and pretreatment is a between-subjects factor in a cross-over factorial design.
  • a typical experiment assessing the interaction between a pretreatment drug and amphetamine use 30 mice, 10 for each level of the pretreatment factor. Prior to any treatments, mice were tested in a 30-min baseline session, which constituted their first exposure to the test chamber. This baseline session is important to characterize the phenotype in the studies of genetically modified mice and is used here to maximize the comparability of the pharmacological and knockout models. In addition, it is found that some prior familiarization with the test increases the comparability of the two subsequent experimental test sessions used for the cross-over design.
  • valproate reduces the hyperactivity produced by amphetamine that is confirmed by a significant pretreatment-by-treatment interaction.
  • Acute Lithium Doses of 1 or 2 mEq/kg LiCl one hour before testing have been shown to reduce the locomotor-activating effects of 3 mg/kg amphetamine in C57 mice (Gould et al 2001). Higher doses of LiCl reduced activity by themselves, but especially the low dose only altered the amphetamine response. Similarly, it is found that 2 mEq/kg LiCl reduces the PPI-disruptive effects of amphetamine. Same two doses of LiCl (1 and 2 mEq/kg or 42.5 and 85 mg/kg i.p.) were used for these experiments, with a separate 3-by-2 design for each sex as in the valproate studies detailed above.
  • clozapine was used in doses of 1 and 3 mg/kg acutely.
  • acute antipsychotic treatment fails to prevent the effects of amphetamine or leads to uninterpretable results
  • chronic treatment regimens were explored.
  • chronic treatments have not been required to block the effects of dopaminergic agonists on PPI (Geyer et al 2001 ; Mansbach et al 1988).
  • mice Model Assess the Ability of Antimanic Treatments to Reverse the
  • DAT KD Dopamine Transporter Knockdown
  • mutant mice For studies of mutant mice, only the offspring of heterozygous matings were used. Genotype was generated, and study cohorts of 200+ mutant mice derived from simultaneous breeding of 20-25 +/- pairs. It is likely that only the +/+ and -/- offspring were used in these drug studies, as it is seldom seen robust phenotypes in the KD +/- mice (though any such phenotype would be pursued avidly). Thus, a given cohort of mutants for testing likely involve 50 +/+ and 50 -/- mice. Both sexes were used with sex being included as a factor in the ANOVA. Meanwhile, the +/- offspring are utilized in the breeding to generate another cohort for further studies.
  • mice 50 and 100 mg/kg valproate were deemed of value, the design were a 3 (pretreatment) by 2 (sex) by 2 (genotype) between-subjects factorial design, with at least 8 mice per cell (96+ mice split into 12 groups). In the absence of interactions with sex, the group sizes become about 16 per cell. Such interactions occurred at least at a trend level in some but not the majority of studies. All mice were first tested in a 30-min baseline characterization session, which were used to create groups matched for overall level of locomotor activity prior to treatment. Two weeks later, mice were tested in a 60-min test session after the appropriate pretreatment.
  • each cohort was typically used in more than one experiment. With a minimum of two weeks between treatments and exposure to the mBPM chambers, it is found that carryover effects from one experiment to another were typically minimal. Nevertheless, groups were counter-balanced according to drug history and assess possible carryover effects by including history as a grouping factor. Any indications of an interaction involving prior test history prompted confirmatory tests in a subsequent experiment. 101391 A fundamental concern with any constitutively mutated animal was that compensatory changes during development may contribute to any observed phenotypes.
  • DAT mutants may be models of compensation. Nevertheless, the comparison of the effects of amphetamine with the abnormalities in DAT mutants began to assess this issue. Such concerns were addressed using temporally controllable alterations of the DAT gene.
  • a doxycycline-sensitive DAT mutant was in development with a normal complement of DAT until given doxycycline. Use of such mice, testing the mutation on different genetic backgrounds would be possibilities in future studies.
  • DAT KD - Chronic Pretreatments Using the chronic pretreatment regimens for valproate and LiCl described above, similar studies were conducted in the mBPM on DAT KD +/+ and -I- mice. Depending upon the size of the cohort available for study, either one or two concentrations of valproate or lithium in the food were examined in a given experiment. Anticipating some variance in blood or serum levels between individuals, groups of 10-12 were initialed for these studies, which could limit any individual study to only one dose of the pretreatment. The prioritization of which chronic regimens to utilize were based on the results of the above studies.
  • DAT KO Dopamine Transporter Knockout
  • DAT KO - Acute Pretreatments, PPI Using the doses of valproate and LiCl described above, the sensitivity of the PPI deficit in DAT KO -/- mice to reversal by antimanic agents was assessed. For each antimanic treatment, it will reduce the PPI deficit seen in the DAT KD -/- mice, as confirmed by a pretreatment by genotype interaction. It is provided that no such interaction on measures of startle reactivity. The offspring of heterozygous matings were genotyped by PCR and tested in a baseline startle test to develop groups matched for startle and PPl prior to drug testing.
  • mice were tested after vehicle or one or two doses of the antimanic agent (depending upon the size of the cohort). If necessary, mice were tested again at weekly intervals after the alternative pretreatment so that pretreatment became a within subject factor. Analytical designs matched those used above.
  • DAT KO - Chronic Pretreatments, PPI The effects of chronic valproate and lithium on the PPI deficits in DAT KO -/- mice were assessed, as described in the above studies. Adjustments in the concentrations of drugs in the food were warranted for the DAT KO -/- mice. Mice were tested on the diet weekly, as repeated testing of
  • PPI was a standard and very effective strategy in mice, rats, and humans.
  • the dietary treatment was continued for up to 4 weeks. Serum lithium levels were assessed using eye-bleeds every two weeks; blood valproate were assessed in each mouse from trunk blood samples taken at sacrifice after the last test.
  • DAT KO Dopamine Transporter Knockout
  • both Dl and D2 DA receptor antagonists reduce the hyperactivity phenotype in the DAT KO -/- mice, but only the Dl antagonist attenuated the perseveration phenotype.
  • D2 but not D 1 receptor antagonism reversed the PPI phenotype in these mice.
  • the three dimensions of inhibitory function can be individually altered pharmacologically even in a mutant mouse that exhibits all three abnormal phenotypes.
  • subchronic (and perhaps acute) treatment with antidepressant medications induces disruptions in the three domains of inhibition DAT-deficient mice that exhibit minimal or no phenotypic abnormalities at baseline (DAT +/- KO and, for PPI, DAT -/- KD) mice.
  • antimanics e.g. lithium and valproate
  • atypical antipsychotics e.g. risperidone and quetiapine
  • DAT KD and KO, PPI Doses of 10 and 20 mg/kg fluoxetine were administered to +/+, +/-, and -/- DAT KD mice prior to tests of PPI. Both males and females were used, with sex included as a factor in the ANOVA. As above, mice were baseline-tested for determination of groups matched for baseline startle and PPI and then tested with each of the 3 pretreatments at weekly intervals. If carryover effects or order interactions were noted, the study was repeated using a between-subjects design.
  • the serotonin selective reuptake inhibitor (SSRI) fluoxetine was first focused on because it is found that a serotonin2A antagonist (M 100907) attenuates the PPI, hyperactivity, and perseverative phenotypes in DAT KO -/- mice (Barr et al 2003). It is provided that the -/- (and perhaps the +/-) knockdown mice exhibited normal PPI after vehicle pretreatment and reduced PPI after fluoxetine. A pretreatment by genotype interaction and appropriate post-hoc comparisons would confirm this finding. 101521 A similar study using acute administrations of the tricyclic antidepressant imipramine were then conducted.
  • the antidepressant unmasked a tendency for deficient PPl in the DAT deficient mice in which the loss of transporter sites was incomplete and insufficient to produce a robust phenotype in the absence of the antidepressant.
  • DAT KQ Doses of 10 and 20 mg/kg fluoxetine were administered to +/+ and +/- DAT KO mice, both males and females. In this case, the -/- mice were not tested because their PPI was already disrupted to the point that it would be unlikely to observe any further disruption after pharmacological treatment. If acute antidepressant treatments do not alter PPI in DAT KD -/- or DAT KO +/- mice, fluoxetine or imipramine were administered chronically using established procedures (Santarelli et al., 2003) and the mice were tested weekly for up to 4 weeks.
  • DAT KD and KO Motor Activity: Similar studies were conducted to assess the effects of antidepressants on motor activity and perseverative patterns of locomotion. Again, it is provided that the antidepressants unmasked a disinhibition phenotype in DAT-deficient mice that are relatively normal without pharmacological treatment. Hence, DAT KD +/+ mice were compared with DAT KD +/- mice after vehicle or an antidepressant treatment (acute or chronic). Similarly, DAT KO +/+ mice were compared with DAT KO +/- mice with and without the antidepressant treatments. The -/- mice were not used in either case, as they already express robust phenotypes.
  • An animal model (which at baseline exhibited deficient PPI, hyperactivity, and perseveration) in which hyperactivity and perseveration were attenuated by both valproate and lithium and in which lithium but not valproate reversed PPl deficits, can receive considerable empirical validation.
  • An animal model that exhibited such a high degree of predictive validity is an invaluable tool for examinations of the neurobiological substrates involved in the expression and/or etiology of BD. Identifying differential effects among the measures of inhibition in manic BD patients facilitates model development and helps to better specify the specific disorder(s) and treatments being modeled. Such discriminations among the three domains of inhibition are likely to be observed in both human and animal experiments.
  • DA D2 antagonists reduce the hyperactivity and PPI deficit, but not the perseverative abnormalities, in DAT KO mice (Ralph et al., 2001).
  • a DA Dl antagonist which does not share with D2 antagonists the ability to block the PPI-disruptive effects of amphetamine (Ralph- Williams et al., 2002), reduces both the hyperactivity and the perseverative locomotion in the DAT KO mice (Ralph et al., 2001).
  • manic BD patients exhibit abnormalities in all three of the domains of inhibition, as do amphetamine-treated or DAT deficient mice, all the antimanic and atypical antipsychotic treatments have uniform effects on all these measures.
  • some treatments have therapeutic effects that can be indexed by one or another of the measures of inhibition differentially after acute versus more chronic treatments.
  • Such information provides further criteria by which to evaluate the specific results that can be derived from the animal models.
  • the profile of deficits across the domains of inhibition at admission may represent clinical responses to particular pharmacological treatments.
  • Some of the measures are rapidly responsive to treatments in a manner that represents the treatment efficacy, or lack thereof, over a longer term.
  • one or another of the measures of disinhibition is non- responsive to treatments and independent of clinical state.
  • Such a measure has utility as a trait marker or endophenotype of BD.
  • PPI deficits in manic BD patients It has been widely reported that patients with clinical features of inhibitory deficits have PPI deficits (Braff et al 2001; Swerdlow et al 2001). Relatively little has been published on PPI in manic BD patients. As shown here and in a recent paper (Perry et al 2001 a), it was the first to demonstrate that BD patients with psychotic mania, tested within 96 hours of acute psychiatric hospitalization, had significant deficits in PPI that were comparable to those of acutely hospitalized schizophrenia patients (Fig. 4).
  • a healthy human volunteer who had extensive experience observing manic bipolar patients, was instructed to generate different "types" of whole body motion while wearing a LifeShirt®.
  • Five different movement patterns were simulated: sitting very still, sitting relaxed with some movement, sitting but fidgeting in the chair, walking in the room, and walking and rocking, respectively. These movement patterns were selected based on prior observations of manic patients. Accelerometry data were sampled for a total of 28 minutes at a 10 Hz sampling rate and were stored numerically in digital units. Inspection of the acceleration distribution revealed a highly skewed density towards few high-acceleration bouts.
  • the logarithmic distribution of accelerations was divided into four equal sized bins.
  • the sequence of accelerations was then transformed into sequences of bin numbers. For example, a small acceleration value followed by a large acceleration value would correspond to a sequence ⁇ 1, 4 ⁇ .
  • Grassberger Grassberger 1989
  • the unique sub-sequence lengths of the accelerations were obtained. The unique subsequence length was determined for each sequence starting at the i* data point and the local dynamical entropy was computed via log (number of data points)/[unique subsequence length].
  • the inverted U-shaped response curve of the dynamical entropy as a measure of perseveration is completely analogous to the inverted U-shaped dose responses previously reported using both dynamical entropy and the spatial scaling exponent, d, in both rat (Paulus & Geyer 1.91) and mouse (Paulus et al 1999a) experiments.
  • Example 1 A cross-sectional study on differences in inhibitory functions between manic BD patients and Normal Comparison Subjects (NCS) as assessed by PPI, levels of motor activity, and perseveration was performed, as indicated in Example 1 below, and a longitudinal follow-up study on the effects of treatment on these functions in manic BD patients was also conducted, as indicated in Example 2 & 3 below.
  • Examples 2 & 3 were structured to complement the animal experiments by addressing how medications affect inhibitory failures in manic BD patients.
  • the BD patients include, but are not limited to, 1) subjects meet diagnostic criteria for Bipolar Affective Disorder (BD), most recent episode manic as determined by the Structured Clinical Interview for DSM-IV (SCID); 2) have young Mania Rating Scale (YMRS) score that is equal to or greater than 20; 3) have no other active Axis I disorder, and 4) have ability to give informed consent as evaluated prior to the study.
  • Normal comparison subjects include, but not limited to, individuals that meet the following criteria: 1) no lifetime history of an Axis I or Axis II diagnosis according to the SCID interviews, and 2) no first-degree relative with a history of psychotic illness. All subjects are between 18 and 55 years of age.
  • Subjects were excluded from the study if they have a neurological disease or damage, or if they have systemic medical illness that may compromise cognitive functioning (e.g., liver disease, etc), history of head injury with a documented loss of consciousness, or DSM-IV defined alcohol or substance abuse or dependence within the last 30 days. Subjects who are under the influence of illegal substances on admission or at the time of Session 3 as determined by urine toxicology screens were terminated from the study. Normal comparison subjects were excluded from the study if they report significant psychopathology, are currently taking a psychoactive substance, or have a first-degree relative with a psychotic illness. Women, minority, and people from different ethnic groups could be involved in the study.
  • Session 1 Manic BD patients were tested within 72 hours of their admission to the hospital for the following measurements and/or assessments:
  • the name and dose of the BD subject's medication were recorded.
  • the YMRS were administered to BD subjects. All subjects again underwent the identical experimental procedure detailed above.
  • Session 3 60% of the BD patients and NCS that were tested at Session 2 were tested.
  • Several methods, such as contacts with patient at discharge, and contacts patients' friends and family members, were used to maximize the follow up rate in manic BD patients.
  • SCID Structured Clinical Interview for DSM-IV
  • the SCID was subjected to a multi-site test-retest reliability study with 592 subjects interviewed and 25 raters (Williams et al 1992). Interrater agreement was considered good at a kappa coefficient of 0.61. When compared to other diagnostic interviews, the SCID showed similar test-retest reliability. It has previously established a 98% agreement for determining Axis I diagnoses using the SCID (Perry et al 2001b).
  • YMRS Young Mania Rating Scale
  • Prepulse Inhibition Test Session Humans: To assess PPI in humans, pairs of small cup electrodes (Ag/AgCI) were placed below and lateral to the right eye over the orbicularis oculi muscle, with a reference electrode on the right mastoid. The subject was then fitted with headphones. Sound levels were measured using continuous tones and a calibrated Quest Sound Level Meter on the A scale, coupled to the headphones by an artificial ear. Subjects were seated upright in a comfortable lounge chair and asked to focus on a small square on the wall. The PPI session consisted of 82115-dB 40 ms bursts of white noise with a 70-dB continuous white noise background.
  • the session began with 1 block of 5 pulse-alone trials. Following this block were 2 blocks of 36 trials each, each containing 12 pulse-alone and 24 prepulse-pulse trials in a pseudorandom order. The 20 ms 86-dB prepulse stimuli preceded the noise burst by 30, 60, or 120 ms. Within each of the 2 prepulse blocks were 6 "hidden" no-stimulus trials where no stimulus was delivered but data were recorded. Therefore there were 4 prepulse-pulse trial types (30 ms, 60 ms, 120 ms, no- stimulus), with 6 of each trial type in each of the 2 blocks. The session ended with a block of 5 pulse-alone trials. Inter-trial intervals averaged 16 s, with a range of 8 to 22 s. Voluntary and spontaneous blinks were excluded from analysis by blindly rated morphological criteria. The session duration was 30 min.
  • PPI is defined as the percent reduction in startle magnitude in the presence of the prepulse compared to the magnitude in the absence of the prepulse [100 - (100 x magnitude on prepulse trial/magnitude on corresponding pulse-alone trial)]. Thus, a large percent score indicates a high degree of PPl, while a smaller percent score indicates less PPl.
  • PPI difference scores magnitude on pulse-alone trials minus magnitude on prepulse trials were also analyzed since percent and difference scores could differ and contribute complementary information. Percent PPI was calculated separately for each of the 3 ISI (30, 60, 120 ms) conditions.
  • the LifeShirt® System (Vivometrics, 2002) is an ambulatory, multi-sensor, continuous monitoring system for collecting, analyzing, and reporting health data.
  • the Sensor array of the LifeShirt® System is embedded in a sleeveless undergarment, made of washable Lycra material that fits snugly and can be worn comfortably for extended periods by individuals of varying girth.
  • a two-axis accelerometer For measurement of body posture (angle deviation from horizontal) a two-axis accelerometer is placed onto the shirt over the sternum. The rectified and integrated accelerometer signal is used to detect periods of physical activity and rest.
  • An on board PDA continuously encrypts and stores the patient's activity and posture physiologic data on a compact flash memory card.
  • VivoLogicTM a proprietary PC -based software, decrypts and processes the recorded data, and provides the viewing of- high-resolution waveforms and trends over time. Summary reports are generated that present processed data in concise, graphical, and numeric formats. Data are then exported in ASCII format for analysis in other software programs. Accelerometry data are sampled at 10 Hz and stored numerically in digital units. From these data, changes in posture, average activity levels, periods of peak activity and total activity levels for specified time frames were derived.
  • FIG. 10181 j Figure 1 1 provides a graphical example of activity data using the LifeShirt®. Note that changes in type of activity were reflected by deflections in the motion data. The continuous high-frequency sampling of activity data also allowed us to derive nonlinear dynamic variables related to motor activity. Two measures to quantify levels of activity and perseveration were obtained. First, levels of activity were obtained as the average acceleration during a given time bin. This measure (shown in the figure) differentiated different types of behavior in terms of their overall activity level. Second, the dynamical entropy, h, were obtained from the sequence of accelerations over time, for a given time bin. To calculate h, all acceleration values were first logarithmically transformed. Then, each acceleration measure wad transformed into a bin number based on equally spaced bins derived from the distribution of accelerations. For example, a typical distribution of accelerations ranged from .01 to 15 local acceleration units.
  • This measure was analogous to a 'local spread of information,' or the rate at which a particular subsequence becomes unique.
  • a technique analogous to nearest-neighbor methods has been suggested to calculate efficiently the average dynamical entropy and can be easily extended to calculate these local dynamical entropies (Schumann & Grassberger 1996).
  • This method determines the uniqueness of a subsequence and calculates the local dynamical entropy via h
  • log(N)/l i; where N corresponds to length of the entire sequence and I i is length of the subsequences that identifies the subsequences that identifies the subsequence as unique.
  • Manic BD patients showed altered inhibitory functioning as measured by prepulse inhibition (PPI). To determine whether manic BD patients show inhibitory deficits in all three domains (PPI, hyperactivity, perseveration), manic BD patients to a group of NCS on these three measures of inhibitory function at admission (Session 1) were examined. The results indicated that manic BD patients exhibit significantly greater deficits on measures of inhibition (less PPI, more hyperactivity, and more perseveration) than NCS.
  • the primary dependent measure for the assessment of PPI are percent PPI in each of 3 prepulse conditions (30, 60, and 120 ms ISI). Multiple conditions were included to ensure that the behavior at different levels was measured in order to detect floor or ceiling effects. Hence, group- or treatment-by-prepulse interactions were not expected. Changes in PPI are most readily interpreted in the context of no changes in startle. Startle reactivity would also be assessed, however, with difference as well as percent PPI scores being used to help interpret the possible contribution of changes in startle to changes in PPl.
  • the primary dependent measure for motor activity was derived from the standard measure of average acceleration from the LifeShirt® device. To quantify the degree of perseveration, the average dynamical entropy was utilized as a function of exposure time. Higher entropy corresponds to increasingly unpredictable sequences of alterations and therefore decreasingly perseverative movement patterns.
  • manic BD patients show rapid and dramatic changes in symptomatic state (McElroy et al 1996). To determine whether the inhibitory dysfunction in these patients is related to clinical state, these patients were examined multiple times. Thus, manic BD patients were tested at three intervals: 1) within 72 hours of hospitalization (Session 1); 2) 7 days later (Session 2); and 3) 28 days later (Session 3). The data provided that manic BD patients showed significant improvement in inhibitory function (increased PPF, decreased hyperactivity, and decreased perseveration) across the three test sessions compared to NCS; and in manic BD patients, decreased inhibitory deficits were related to decreased symptoms as measured by YMRS scores over the three test sessions.
  • divalproex sodium, carbamazepine, lamotrigine alone
  • treatment with an atypical antipsychotic medication alone e.g. risperidone, olanzapine, quetiapine
  • treatment with a combination of lithium or an anticonvulsant plus an atypical antipsychotic medication did not include all possible treatment combinations, but were the most common and therefore largest groups at NBMU.
  • locomotor activity measures are used to assess effects of therapeutics in animals. Hyperactivity occurs in various psychiatric disorders including BD and ADHD. Surprisingly, few studies have examined whether measurement of locomotor activity in humans could be useful biomaker. This study used video- tracking to measure locomotor activity to measure distinguishable patterns of human behavior.
  • Manic BD and SCZ patients were tested within 72 hours of admission to a psychiatric hospital.
  • NC subjects were retested at same time intervals as manic BD patients.
  • hBPM refers to a novel room furnished with ten engaging stimuli and no chairs. Subjects are directed inside with no instruction except to wait for the experimenter.
  • Figure 26 shows a wearable ambulatory monitoring device, namely, the LifeShirt®-Clinical System (VivoMetrics, 2002). Motor activity is quantified with a centrally mounted accelerometer embedded in the device.
  • hBPM and LifeShirt®-Clinical system motor activity in Session One for manic BD patient, SCZ patients, and NC subjects was presented in Figure 27, while motor activity across all three sessions for manic BD patients and NC subjects were presented in Figure 28.
  • the following Table shows Pearson r correlation coefficients between motor activity and YMRS Total Scores for manic BD patient.
  • hBPM represents an original attempt to objectively capture motor hyperactivity in manic BD patients.
  • the data provide that quantitative assessment of hyperactivity is only modestly correlated with observer-rated symptoms of mania, highlighting the need for objective assessment.
  • the data also provide that motor activity in the hBPM does not show significant short-term or long- term habituation.
  • hBPM may be a useful paradigm for translational studies comparing locomotor activity in humans and in mouse models for mania.
  • the hBPM has been used to assess and characterize behaviors in bipolar disorder.
  • Mania is the defining feature of Bipolar Disorder (BD).
  • BD Bipolar Disorder
  • Hyperactivity is a cardinal symptom of mania, traditionally measured in humans using observer-rated scales.
  • Multivariate assessment of unconditioned locomotor behavior using the rat Behavioral Pattern Monitor (BPM) has shown that hyperactivity includes complex multifaceted behaviors.
  • the BPM has been used to demonstrate differential effects of drugs on locomotor activity and exploratory behavior in rats. Studies of genetically engineered mice in a mouse BPM have confirmed its utility as a cross-species tool.
  • the original Open Field was expanded to include computer-monitored activity chambers based on photobeams or video-tracking as well as measures of exploratory behaviors such as rearings or holepokes in holeboard chambers (Berlyne 1966, File and Wardill 1975, Geyer 1990, Geyer and Paulus 1996, Makanjuola et al. 1977, Paulus and Geyer 1996).
  • rBPM rat Behavioral Pattern Monitor
  • the rBPM is a 30.5 by 61 cm chamber equipped with rearing touchplates on the walls and 10 holes in the floors and walls that serve as discrete stimuli for rodents to investigate.
  • This system collects information about the locomotor movements and investigatory responses (rearings and holepokes) of rats at high levels of temporal and spatial resolution (Geyer et al. 1986).
  • the multivariate profiles of locomotor and investigatory behaviors provided by the rBPM helped to elucidate the behavioral characteristics and neuropharmacological mechanisms of psychoactive drugs (Adams and Geyer 1982, Flicker and Geyer 1982).
  • Multivariate profiles have many advantages over univariate assessments that are limited to measures of the amount of activity. These advantages are most clearly demonstrated in research assessing the effects of stimulant drugs on rodents. Depending upon dose, drugs such as amphetamine, apomorphine, caffeine, 3-4- methylenedioxymethamphetamine (MDMA), nicotine, phencyclidine and scopolamine all induce similar increases in the amount of activity, as measured in the Open Field, photobeam activity chambers, or the BPM (Bushnell 1987, Collins et al. 1979, Fink and Smith 1979, Fitzgerald et al. 1988, Geyer et al. 1986, Gold et al. 1988, Gould et al. 2001 , Krebs-Thompson et al. 1998, Kulkarni and Dandiya 1975, Meliska and Loke 1984, Paulus and Geyer 1992, Sessions et al. 1980).
  • drugs such as amphetamine, apomorphine, caffeine, 3-4- methylenedioxymethamp
  • phencyclidine can raise or lower exploratory levels dependent upon dose (Krebs-Thompson et al. 1998).
  • dopamine releaser amphetamine stimulates exploratory behavior in the holeboard apparatus and rBPM
  • the direct dopamine agonist apomorphine inhibits holepoking behavior (Geyer et al. 1986, Makanjuola et al. 1977).
  • MDMA a derivative of amphetamine that preferentially releases presynaptic serotonin rather than dopamine, also reduces holepoking and rearing behavior (Gold et al. 1988).
  • Spatial scaling exponent measures the hierarchical and geometric organization of behavior. Specifically, d is based on the principles of fractal geometry and describes the degree to which the path taken within an enclosure by the subject is one-dimensional or two-dimensional. To obtain spatial d, the distance traveled is plotted against the number of micro-events (defined as the smallest change that can be observed) using a double-logarithmic coordinate system, and a line of fit between these two variables is generated (PauJus et al. 1990, Ralph et al. 2001). Spatial d typically varies between 1 (a straight line) and 2 (a filled plane), with values closer to 1 reflecting straight movements and values closer to 2 reflecting highly circumscribed, local movements.
  • stimulants can be differentiated into those that do or do not affect exploratory behavior and/or behavioral organization (see Fig 13 comparing saline vs. amphetamine, phencyclidine, and scopolamine locomotor patterns).
  • apomorphine, MDMA, phencyclidine and scopolamine increase spatial CV, reflecting the generation of more repetitive patterns of movements
  • amphetamine increases the variety of different movements and therefore lowers spatial CV (Geyer et al. 1986, Gold et al. 1988, Lehman-Masten and Geyer, 1991 ).
  • neither nicotine nor caffeine had any effect on this measure.
  • Nicotine is the prototypical Iigand of the nicotinic acetylcholine receptors, while caffeine may act via the GABAergic system, which can indirectly affect dopamine and norepinephrine functions.
  • the myriad effects of amphetamine are a result of increased release of dopamine, serotonin, and norepinephrine, which occur via amphetamine-induced blockade of the respective transporters.
  • other drug-induced manipulations of these neurotransmitter systems can also cause hyperactivity and altered exploratory behavior and locomotor patterns.
  • Locomotor Behavior Homologies From Rat to Mice: The use of simple photobeam activity chambers (Young et al. 2007) or the open field test (Barr et al. 2004, Crusio 2001) has predominated in mouse locomotor research. A video-tracking system was used to assess motor activity in mice. As provided, psychostimulant drugs such as amphetamine produce similar degrees of activation in mice as in rats. Fairly dramatic differences in the patterns of activation produced by amphetamine in different strains of inbred and outbred mice were readily demonstrable (Ralph et al. 2001).
  • mice with reduced DAT levels exhibit significantly increased extracellular dopamine activity similarly to BD patients (Vawter et al. 2000,
  • DAT knockdown mice lacking only 90% of the DAT, also exhibit a hyperactive phenotype characterized by more perseverative patterns of locomotor behavior reflected in lower spatial d values (Ralph- Williams et al. 2003). If indeed a dysregulated dopamine system underlies some of the key symptoms of mania, it may be provided that pharmacological agents that successfully treat manic symptoms would attenuate the hyperactivity displayed by the DAT KD mutant mice. Indeed, when the DAT KD mice were treated with 100 mg/kg valproate, a dose that had no effect on WT mice, their hyperactivity was reduced significantly.
  • mBPM a mouse version of the BPM, namely, mBPM, was developed and designed to overcome the lack of exploratory behavior assessment in the video-based open field test (Risbrough et al. 2006).
  • the utility of the mBPM was demonstrated in the description of the different locomotor activity, exploratory behavior, and behavioral organization phenotypes of dopamine receptor KO mice and their responses to MDMA (Risbrough et al. 2006).
  • MDMA increased activity, lowered spatial d, and increased spatial CV in WT littermate mice in a similar pattern of responses to that observed in rats.
  • the mBPM was also sufficiently sensitive to differentiate between the phenotypes of Dl, D2, and D3 receptor KO mice.
  • Dl KO mice exhibited an exaggerated responsiveness to the MDMA-induced increases in locomotor activity, while D2 KO mice exhibited a reduced amount of MDMA-induced activation (Risbrough et al 2006).
  • Activity levels of D3 KO male mice were unaffected by MDMA while females displayed a reduced expression of MDMA-induced locomotor activation.
  • D3 KO mice did not exhibit the same immediate MDMA induced-increase in perseverative locomotor behavior (spatial CV).
  • Dl KO mice While Dl KO mice exhibited straighter locomotor patterns (lower spatial d) than their WT counterparts, the spatial d measures of the Dl KO and WT mice were similarly lowered following MDMA administration (Risbrough et al. 2006). Hence it was suggested that Dl receptors may contribute to the locomotor pattern quality, i.e. linear vs. circumscribed movement (spatial d), while D2 receptors may contribute to perseverative or thigmotactic locomotor effects of MDMA (spatial CV). This study demonstrates the utility and cross-species generalizability of the BPM. Moreover, the mBPM data collected to date does suggest that a factor analysis could be performed similarly to that of rats, which would likely yield the emergence of exploratory behavior as a third independent factor.
  • scales may not be optimal in detecting potentially subtle alterations in activity levels nor are they informative about qualitative aspects of hyperactivity that may distinguish certain psychiatric populations from others.
  • several diagnostic groups may present with symptoms of hyperactivity but they may be qualitatively distinct and thus reflect different underlying neural circuitry abnormalities.
  • the human Behavioral Pattern Monitor (human BPM) was developed, as an analog of the rodent BPM and a method with which to sensitively quantify the characteristics of human hyperactive and exploratory behavior.
  • the hBPM reflects a "reverse-translational" approach using the existing rich animal literature to inform its development. This approach contrasts with other well- established translational paradigms such as prepulse inhibition of the startle response, an index of sensorimotor gating.
  • the assessment of prepulse inhibition in psychiatric patients was first developed in humans using the startle eyeblink response (Braff et al. 1995).
  • the hBPM takes place in a 9' by 14' room that the human participant has not been exposed to and therefore is, like the rodent BPM, a novel and unfamiliar environment.
  • multiple measures of motor activity can be collected, including spatial d, entropy h, transitions, distance traveled, and others.
  • the objects provide an analog of the exploratory holes in the walls and floor of the rodent BPM chambers. Participants are directed into the room with little instruction or direction and are asked to wait for the experimenter to return.
  • the hBPM session has been fifteen minutes long in the studies to date.
  • Data in the hBPM are gathered using three sources of measurement: 1) collection of physiologic data, namely motor activity of the subject's torso, using an accelerometer embedded in an ambulatory monitoring device that the participant wears; 2) x-y coordinates of the subject's spatial location in the BPM, extracted from digital video recording; and 3) experimenter ratings of exploratory activity, obtained by carefully scoring the video recording of the BPM session and measuring events such as interactions with objects.
  • These three sources of measurement capture different qualitative aspects of motor and exploratory behavior, and yet may also be intercorrelated in the case of certain types of behavior, as will be illustrated below.
  • the LifeShirt® System (Vivometrics 2002) is an ambulatory, multi-sensor, continuous monitoring system that collects objective physiologic data through various sensors, including respiratory inductive plethysmography bands, which measure pulmonary function, electrical activity of the myocardium via a 3-lead EKG, and activity/posture via a two-axis accelerometer.
  • the sensor array of the LifeShirt® System is embedded in a sleeveless undergarment.
  • a two-axis accelerometer is placed onto the shirt over the sternum, and the rectified and integrated accelerometer signal is used to detect periods of physical activity and rest.
  • An onboard PDA continuously encrypts and stores the patient's activity and postural physiologic data on a compact flash memory card. Accelerometry data are sampled at 10 Hz and stored numerically in digital units. Thus, one measure of the amount of motor activity is obtained by averaging acceleration values over the three five-minute intervals of the human BPM session. Exemplars of the acceleration values derived from individual subjects are provided in Figure 17.
  • the room is also equipped with a camera and fish-eye lens system hidden in a ceiling vent.
  • the images from the camera are stored in digital format on a computer in the adjacent room, with a frequency of 30 frames per second.
  • the digital videos of subject's activity in the human BPM are subjected to frame-by-frame analysis with proprietary software (Clever Systems, Inc. 1999), which generates x and y- coordinates of the subject's successive locations. Because the software specifically tracks the blue LifeShirt® vest, the coordinate positions reflect the position of the upper part of the subject's torso.
  • these x-y coordinates are used to plot the path of the subject and to count time spent and transitions between nine arbitrarily defined regions of the hBPM. These regions are analogous to our definition of nine areas of the rodent BPM (Geyer et al. 1986), namely the four corners, four walls, and the center. Delineation of these regions allows to obtain a distribution of amount of time spent in each region as well as to measure the number of transitions, defined identically to the rodent work as movement from one region to an adjacent one.
  • transitions between regions and dwell times within specific regions can serve as additional measures to describe different aspects of locomotor activity and to complement the accelerometry data.
  • the digitized video images enable detailed assessments of the subject's interactions with the 10 objects placed in the room, in analogy to the rodent's investigatory behavior directed toward the 10 holes placed in the walls and floors of the rodent BPM chambers.
  • the continuous, high-frequency sampling of motor activity data also allows to calculate dynamical entropy, h, which is comparable to the entropy measure mentioned above in the context of our animal studies.
  • Dynamical entropy quantifies the predictability of a given level of activity based upon preceding patterns of activity.
  • This acceleration-derived entropy measure captures, a unique feature of human locomotor behavior, i.e. how sequences of acceleration events are organized in time. More importantly, it can also be used to derive entropy "signatures" for specific and distinctive patterns of motor behavior. For example, in initial standardization studies, average entropy values were generated for motor behaviors that subjects exhibited in response to audiotaped instructions, e.g.
  • FIG. 18 illustrates that videotape ratings of a subject's walking behavior corresponded precisely with the entropy-derived mathematical "signature" of walking. Given that dynamical entropy h can characterize disordered movement as well as perseverative movement as described above in the animal studies, it provides a potentially informative measure of how human motor behavior is organized across time.
  • the hBPM is one of the central measures that are used in an investigation of inhibitory deficits in bipolar mania.
  • the original basis for developing the hBPM was to conduct parallel, cross-species studies of inhibitory problems that are features of the mania of BD and to extend the paradigm to other conditions such as schizophrenia, where multivariate assessment of motor behavior can reveal distinctive characteristics of the illness.
  • the importance of this study was to develop and validate rodent models of mania, which has been identified as a need in the literature (Einat 2006).
  • the hBPM is an example of a "reverse-translational" approach to neuroscience research: whereas most paradigms that are eventually applied to both humans and animals are first developed in humans and then modified to be tested in animal models, the hBPM is unique in that it was developed as an analog to a widely used and highly influential animal paradigm, the open field as elaborated into the rodent BPM.
  • the motor behavior of human clinical populations both in terms of some of the more straightforward measures such as accelerometry and video ratings, as well as the more complex measures of entropy and patterns of sequential movements in space.
  • FIG. 17 illustrates representative case examples of hBPM data for the clinical populations as well as the non-patient cohort.
  • the x-y coordinate tracings of the manic BD patient clearly show a very high level of activity in the BPM (Fig. 17b). Both the average acceleration and the number of transitions during the BPM session are substantially higher than those of the schizophrenia patient (Fig. 17c) or the healthy comparison subject (Fig. 17a).
  • the manic patient exhibits markedly more interactions with the exploratory objects.
  • the schizophrenia patient exhibits very low motor activity, little exploration of objects, and a higher spatial d, signifying restricted and localized activity.
  • the striking difference between the manic BD and the schizophrenia patient once again highlights the importance of multivariate assessment of activity, where measurement of multiple parameters may yield distinct "signatures" of locomotor activity that characterize and differentiate these two disorders.
  • the hBPM may be able to quantitatively assess an obvious and meaningful difference between two acutely ill populations who, during acute states, are often difficult to distinguish from one another because the behavioral presentation of both patient groups is dominated by psychotic and mood symptoms (Pini et al. 2004).
  • the potential objective, sensitive, and multivariate characterization of hyperactivity that is afforded by the hBPM offers many directions for further research.
  • One application would be to conduct pharmacological manipulations in parallel animal and human studies. For example, while the effects of stimulants on rodent motor behavior have been thoroughly characterized in the rodent BPM, studying stimulant- induced hyperactivity in the hBPM may help to further elucidate the behavioral features of an acute hyperdopaminergic state in healthy humans.
  • the hBPM may be useful in testing the efficacy of compounds for characterizing disorders that have hyperactivity as a central symptom. Such comparisons could include patients with BD, schizophrenia, schizoaffective disorder, and attention-deficit/hyperactivity disorder (ADHD) as well as developmental illnesses such as autism spectrum and impulse control disorders.
  • ADHD attention-deficit/hyperactivity disorder
  • the hBPM is an important example of cross-fostering translational research. Given the importance of hyperactivity in many psychiatric disorders in general and in bipolar mania in particular, it is surprising that experimental approaches to measure locomotor behavior empirically in humans have not been more abundant in the literature. It is provided that locomotor behavior in rodents is a complex phenotype that is not sufficiently characterized by quantifying only the amount of behavior. However, measures that quantify its temporal, spatial, and dynamic organization have proven to be valuable tools to differentiate the contributions of different neural transmitter systems on locomotor and exploratory behavior. Similarly, it is provided that multivariate approaches to human locomotor and exploratory behavior will provide powerful insights into the neural bases of these behaviors and may provide new biomarkers as targets for the development of novel antimanic agents.
  • Minassian A Paulus MP, Perry W (in press) Increased sensitivity to error during decision-making in Bipolar Disorder patients with acute mania. Journal of Affective Disorders
  • Minassian A Maher W (2003) Visual scanning and complex problem-solving deficits in schizophrenia. Schizophrenia Research 60: 267-268. Minassian A, Perry W, Carlson M, Pelham M, DeFilippis N (2003) The Category Test Perseverations, Loss of Set, and Memory Scales: Three new scales and their relationship to executive functioning measures. Assessment 10: 213-221
  • Swerdlow NR (1996) Cortico-striatal substrates of cognitive, motor and sensory gating: Speculations and implications for psychological function and dysfunction.
  • Panksepp J (ed) Advances in Biological Psychiatry (Vol. 2). JAI Press Inc., Greenwich, CT, pp 179-208 Swerdlow NR, Geyer MA, Braff DL (2001) Neural circuitry of prepulse inhibition of startle in the rat: Current knowledge and future challenges.

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Abstract

La présente invention propose un paradigme humain, précisément, un moniteur du profil comportemental humain (hBPM), qui est analogue à un paradigme animal, et un procédé d'utilisation de celui-ci, pour valider les modèles de maladies psychiatriques des animaux rongeurs. La présente invention propose en outre une approche translationnelle de l'utilisation de mesures caractérisant le comportement locomoteur des rongeurs pour une application dans le comportement locomoteur des humains en utilisant le hBPM dans les troubles neuropsychiatriques, tels qu'un trouble bipolaire. En outre, la présente invention propose d'utiliser le hBPM pour caractériser l'hyperactivité, différencier les groupes de diagnostic, ou l'accoutumance à l'étude, ainsi qu'une mesure potentielle de l'efficacité des médicaments, et l'évaluation des effets des médicaments sur la cognition.
PCT/US2007/072359 2006-06-28 2007-06-28 Moniteur du profil comportemental humain et son procédé d'utilisation WO2008003044A2 (fr)

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US8163964B2 (en) 2006-11-15 2012-04-24 E. I. Du Pont De Nemours And Company Processes for producing pentafluoropropenes and certain azeotropes comprising HF and certain halopropenes of the formula C3 HClF4
CN106999049A (zh) * 2014-11-25 2017-08-01 皇家飞利浦有限公司 调节睡眠期间的感官刺激的持续时间以增强慢波活动的系统和方法
CN107106094A (zh) * 2014-12-16 2017-08-29 皇家飞利浦有限公司 注意力缺陷的评估
WO2020237043A1 (fr) * 2019-05-22 2020-11-26 President And Fellows Of Harvard College Test d'inhibition de pré-impulsion tactile humaine
EP3766423A1 (fr) * 2019-07-19 2021-01-20 Vasilios Chatzatoglou Dispositif et procédé de détection d'un comportement humain anormal possible
US11434244B2 (en) 2018-05-29 2022-09-06 President And Fellows Of Harvard College Compositions and methods for reducing tactile dysfunction, anxiety, and social impairment
US11547706B2 (en) 2016-06-08 2023-01-10 President And Fellows Of Harvard College Methods and compositions for reducing tactile dysfunction and anxiety associated with autism spectrum disorder, Rett syndrome, and Fragile X syndrome
US12077512B2 (en) 2019-03-25 2024-09-03 President And Fellows Of Harvard College Compositions and methods for reducing tactile dysfunction, anxiety, and social impairment

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US20030100998A2 (en) * 2001-05-15 2003-05-29 Carnegie Mellon University (Pittsburgh, Pa) And Psychogenics, Inc. (Hawthorne, Ny) Systems and methods for monitoring behavior informatics

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US20030100998A2 (en) * 2001-05-15 2003-05-29 Carnegie Mellon University (Pittsburgh, Pa) And Psychogenics, Inc. (Hawthorne, Ny) Systems and methods for monitoring behavior informatics

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8163964B2 (en) 2006-11-15 2012-04-24 E. I. Du Pont De Nemours And Company Processes for producing pentafluoropropenes and certain azeotropes comprising HF and certain halopropenes of the formula C3 HClF4
CN106999049A (zh) * 2014-11-25 2017-08-01 皇家飞利浦有限公司 调节睡眠期间的感官刺激的持续时间以增强慢波活动的系统和方法
CN106999049B (zh) * 2014-11-25 2021-03-23 皇家飞利浦有限公司 调节睡眠期间的感官刺激的持续时间以增强慢波活动的系统和方法
CN107106094A (zh) * 2014-12-16 2017-08-29 皇家飞利浦有限公司 注意力缺陷的评估
US11547706B2 (en) 2016-06-08 2023-01-10 President And Fellows Of Harvard College Methods and compositions for reducing tactile dysfunction and anxiety associated with autism spectrum disorder, Rett syndrome, and Fragile X syndrome
US11434244B2 (en) 2018-05-29 2022-09-06 President And Fellows Of Harvard College Compositions and methods for reducing tactile dysfunction, anxiety, and social impairment
US12084451B2 (en) 2018-05-29 2024-09-10 President And Fellows Of Harvard College Compositions and methods for reducing tactile dysfunction, anxiety, and social impairment
US12077512B2 (en) 2019-03-25 2024-09-03 President And Fellows Of Harvard College Compositions and methods for reducing tactile dysfunction, anxiety, and social impairment
WO2020237043A1 (fr) * 2019-05-22 2020-11-26 President And Fellows Of Harvard College Test d'inhibition de pré-impulsion tactile humaine
EP3972595A4 (fr) * 2019-05-22 2023-08-02 President and Fellows of Harvard College Test d'inhibition de pré-impulsion tactile humaine
EP3766423A1 (fr) * 2019-07-19 2021-01-20 Vasilios Chatzatoglou Dispositif et procédé de détection d'un comportement humain anormal possible

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