CN110301363B

CN110301363B - Animal cognitive behavior testing method

Info

Publication number: CN110301363B
Application number: CN201910559926.7A
Authority: CN
Inventors: 罗墨轩; 杨星; 毕国强; 王立平
Original assignee: University of Science and Technology of China USTC
Current assignee: University of Science and Technology of China USTC
Priority date: 2019-06-24
Filing date: 2019-06-24
Publication date: 2021-07-09
Anticipated expiration: 2039-06-24
Also published as: CN110301363A

Abstract

An animal cognitive behavior testing device and testing method based on multi-modal stimulation, the device comprising: the multi-arm labyrinth comprises a plurality of channels serving as labyrinth arms and extending to different directions from a central area of the labyrinth, wherein a display screen and an acoustic source are arranged at the inlet of one or more channels, and the tail ends of the channels are closed; the camera device is positioned above the multi-arm maze and is used for acquiring images of animals in the multi-arm maze; and the controller is connected with the display screen, the sound source and the camera device and used for controlling the image displayed by the display screen and the sound emitted by the sound source and recording and counting the image data obtained by the camera device. The invention can meet the requirements of more complex animal learning and memory experiments.

Description

Animal cognitive behavior testing method

Technical Field

The invention belongs to the field of scientific research instruments for animal behavioral experiments, and particularly relates to a device for testing animal cognitive behaviors by giving multiple sensory stimuli (multi-modal stimuli) and an animal cognitive behavior testing method based on the device.

Background

The behavior is the final output of brain activity. Therefore, if one wants to understand the learning and memory performance of an animal under drug action or brain damage, one needs to observe its behavior in a specific task. In scientific experiments, the influence of various irrelevant factors in the environment on behaviors needs to be eliminated, and the behaviors need to be quantified, so that the animals need to be placed in a behavioristics device. Therefore, it is often the key to design a good behavioural device to successfully perform the relevant experiments.

One currently popular type of behavioral device for testing learning and memory in animals is a multi-arm maze. The maze consists of six or eight equal-length arms radiating from a central platform, often with food serving devices at the extreme ends. According to the strategy of analyzing the feeding of the small animals (such as mice), namely parameters such as the times of entering each arm, time, correct times, wrong times, routes and the like, the spatial memory capacity of the experimental animals can be reflected.

CN103390193A describes an automatic training device modified by the classic eight-arm maze. Eight channels are all one-way channels, and the tail end of each channel is provided with an animal turning area. The back of the rat is fixed with an electric stimulation backpack which receives instructions from the computer in a Bluetooth mode. When the rat entered the tunnel, a camera above the maze recorded and transmitted the image to the computer, which programmed the analysis to determine whether to stimulate the rat. This enables automatic behavioral training in rats.

CN202722231U discloses a more complex eight-arm maze training device. Baits at the ends of some of the arms reward the animal entering the arms; or power up some arms, apply a shock to the incoming animal, and so on. And complete various conditional and unconditional stimulation environments are established through the stimulation-response modules such as sound, light, electricity and the like, and the memory ability of the animals to reward or punishment areas is trained. Such multiple stimulation modes make the device have strong experimental functions.

However, the range of stimuli presented by the above-described exercise devices has limitations. Because the stimulation element is relatively simple, the stimulation pattern is too single. The stimulation pattern of the first patent mentioned above is only the intensity of the current; the second patent only discloses the presence or absence of food and the on/off of the point sound source (horn) and the point light source (bulb) and the intensity of electric stimulation, but the stimulation mode is monotonous and cannot be programmed to realize the change. When the experimental animal selects one arm of the maze and is ready to enter, the stimulation is not changed regularly in space and time and cannot be controlled by a program, so that the advanced cognitive function of the experimental animal cannot be researched. Therefore, in order to meet the requirements of more complex animal learning and memory experiments, a novel maze-like training device needs to be developed.

Disclosure of Invention

In view of the above, the invention provides a device and a method for testing animal cognitive behaviors based on multi-modal stimulation, which are used for meeting the requirements of more complex animal learning and memory experiments.

In order to achieve the above object, in one aspect, the present invention provides an animal cognitive behavior testing device based on multi-modal stimulation, comprising:

the multi-arm labyrinth comprises a plurality of channels serving as labyrinth arms and extending to different directions from a central area of the labyrinth, wherein a display screen and an acoustic source are arranged at the inlet of one or more channels, and the tail ends of the channels are closed;

the camera device is positioned above the multi-arm maze and is used for acquiring images of animals in the multi-arm maze;

and the controller is connected with the display screen, the sound source and the camera device and used for controlling the image displayed by the display screen and the sound emitted by the sound source and recording and counting the image data obtained by the camera device.

In some embodiments, the multi-arm labyrinth has no less than 4, preferably 6 to 8, passages.

In some embodiments, the animal cognitive behavioral testing apparatus further comprises an integrated partition plate, the integrated partition plate is disposed at an inlet of the passage, and the display screen and the sound source are disposed on the integrated partition plate.

In some embodiments, the animal cognitive behavioral testing device further comprises a hollow housing, the multi-arm labyrinth disposed within the hollow housing.

In some embodiments, a cover plate is disposed on the hollow housing, and the camera device is disposed below the cover plate.

In some embodiments, the display screen is a liquid crystal display screen or an LED display screen, and preferably, each display screen is capable of independently displaying different images under the control of the controller.

In some embodiments, the sound sources are speakers or buzzers, preferably the sound frequency, sound waveform and/or volume of each sound source can be independently varied under the control of the controller.

In some embodiments, the camera is a visible light camera or an infrared camera.

In another aspect, the invention provides a method for testing animal cognitive behaviors by using the testing device, which comprises the following steps:

(1) a training stage: placing food at the end of one of the arms of the multi-arm maze, displaying different images statically on each display screen and making each sound source emit different sounds, placing the animal in the center of the multi-arm maze, when the animal searches for a predetermined time or finds the food, placing the animal back to the center of the multi-arm maze, and repeating the training for a plurality of times, preferably 3-5 times;

(2) and (3) a testing stage: under the image stimulation and/or sound stimulation different from the training stage, the animal is placed in the center of the multi-arm maze, the image data obtained by the camera device is recorded and counted, and the cognitive behaviors of the animal are analyzed.

In some embodiments, the testing phase comprises placing the animal in the center of the multi-arm maze, recording and counting image data obtained by the camera device, and analyzing the short-term visual memory and visual positioning ability of the animal under the condition that the sound sources are turned off or the sound sources exchange the sound with each other while the images displayed by the display screens are kept unchanged;

under the condition that the display screens are closed or the display screens exchange images with each other and the sound emitted by each sound source is kept unchanged, the animal is placed in the center of the multi-arm maze, image data obtained by the camera device is recorded and counted, and the short-time auditory memory and auditory positioning capability of the animal are analyzed;

and/or under the condition that the sound sources periodically exchange the sound of each other and the display screens periodically exchange the images of each other, placing the animal at the center of the multi-arm maze, recording and counting the image data obtained by the camera device, and analyzing the response condition of the animal to the periodic stimulation.

In some embodiments, the method further comprises an adaptation phase comprising placing the animal in a multi-arm maze and allowing it to explore for a predetermined time, for example 20min-1h, preferably 30-40min, in the absence of food, image and sound stimuli.

In some embodiments, the animal is a rodent, cat, dog, or monkey.

Compared with the prior art, the invention has the following beneficial effects:

the invention adopts a set of experimental device to finish three types of experiments of smell stimulation (smell of placed food), image stimulation and sound stimulation respectively or simultaneously. And the given images are displayed on the display screen by program drive, and the sound is generated by a sound source driven by the program, so that the two stimuli can be designed by programming, and the mode can have certain complexity, and effectively influence the advanced cognition and behavior of experimental animals such as mice. And the stimulation modules which are independently controlled are arranged on the integrated partition plate of each arm, so that the stimulation can be further spatially arranged and combined, and the stimulation types are enriched.

The camera transmits behavior tracking related to the small animals, and automatically generated experimental data can be analyzed in real time to further control image or sound stimulation to form closed-loop operation; and the types and the duration of the small animal behaviors can be counted after the fact that the small animal behaviors are analyzed.

The whole device has rich functions, high data precision and capability of carrying out repeated behavior quantitative analysis. The animal cognitive behavior testing method based on the device can simultaneously and effectively evaluate the responses of the animals to short-time memory and space positioning of vision and hearing and response conditions of complexity and periodic stimulation respectively, and can be used for understanding the learning and memory performance of the animals under the action of drugs or brain damage state.

Drawings

FIG. 1A is a top view of an animal cognitive performance testing device (not including a cover plate) in an embodiment of the present invention;

FIG. 1B is a 3D perspective view (from the bottom) of an animal cognitive behavioral testing apparatus according to an embodiment of the present invention;

FIG. 2A is a view of the baffle plate facing the center of the labyrinth in the embodiment of the present invention;

FIG. 2B is a view of the side of the partition plate facing away from the center of the labyrinth in the embodiment of the present invention;

FIG. 3 is a schematic structural diagram (inner side structure) of a cover plate according to an embodiment of the present invention;

FIG. 4 is a schematic circuit diagram of an apparatus according to an embodiment of the present invention;

1. a hollow housing; 2. the center of the maze; 3. an integrated separator plate; 4. a labyrinth arm; 5. a display screen; 6. A sound source; 7. a cover plate; 8. a cover plate gap; 9. a camera; 10. a central hole of the cover plate; 11. and a control module.

Detailed Description

In order that the objects, technical solutions and advantages of the present invention will become more apparent, the present invention will be further described in detail with reference to the accompanying drawings in conjunction with the following specific embodiments.

The existing multi-arm maze training devices and similar animal experimental boxes have limitations in stimulation patterns, i.e. they cannot give visual image patterns and auditory sound waveforms and program-controlled stimulation when the experimental animal performs the corresponding behavioral tasks. Therefore, the device for testing the complex cognitive behaviors of the animals is creatively integrated and manufactured by using the display screen, the sound source and the controller. Compared with other multi-arm maze improvement modes, such as an animal behavior research method that the stimulation image is printed on paper and then is attached to an experimental device, the device of the invention can change the stimulation pattern through programming, and is not statically displayed; and the whole process does not need manual operation of people on the experimental device, thereby avoiding the influence of human intervention. The device of the invention can generate abundant stimulation, can provide any complex image sequence on the image and adjust the property (adjusting contrast, Gaussian blur and the like), can generate selected waveform stimulation on the sound and adjust the parameter (frequency and the like), and achieves the aim of researching complex behavior cognition of small experimental animals.

The embodiment of the invention provides an animal cognitive behavior testing device based on complex and multi-mode dynamic stimulation, and the test box comprises four modules: the device comprises an experiment box body, a stimulation module (comprising a 1.8-inch small liquid crystal sheet, a small horn loudspeaker and corresponding lines), a recording module (a camera) and a control module (a single chip microcomputer or an external computer).

The experimental box is shown in fig. 1A and 1B, and adopts the basic design style of a six-arm maze. The inner labyrinth is made of common aluminum alloy, the integral design is adopted, the material can be made of other alloys or plastics, and the style can be changed into a seven-arm or eight-arm labyrinth according to the requirement. The diameter is 60cm, the arm length is 20cm, the arm width is 10cm, and the arm height is 8 cm. Each of the six arms 4 has a slot at the end near the centre 2 of the maze for holding an integrated baffle 3 with a stimulation module. The whole inner labyrinth is arranged in the hollow cylindrical shell 1 and is made of an acrylic plate. And then covered by a cover plate 7 with a camera 9.

The hollow cylindrical shell 1, the integrated partition plate 3 and the cover plate 7 of the embodiment of the invention are made of acrylic plates, and the integrated partition plate 3, the cover plate center hole 10 and the cover plate gap 8 on the cover plate 7 are finished by a factory, as shown in fig. 3. The six-arm maze was placed in the housing in the experiment. The material can also adopt other alloys or plastics, the styles of the cylindrical shell and the cover plate are changed into a prismatic shell and a polygonal cover plate according to requirements, and when opaque materials such as alloys are selected, a light source can be arranged in the device to be beneficial to a camera to acquire images or an infrared camera is selected.

As shown in fig. 2A and 2B, the stimulation module is located on the integrated partition 3, and the display screen 5 (e.g., 1.8 inch small lcd) located on the front side and the sound source 6 (e.g., small horn speaker) located on the back side can respectively provide visual and sound stimulation to the small animal. The signal lines of the two are communicated with an external control module 11 (such as a singlechip or a computer) through a cover plate notch 8 on the periphery of the cover plate 7. The single chip microcomputer or the computer adjusts input signals through signal lines connected with the single chip microcomputer or the computer, and all the input signals can be executed through numbered programs on the single chip microcomputer or can be operated and set in real time through computer programs.

The 1.8-inch small liquid crystal display screen provided by the embodiment of the invention can be purchased in the market. In the experiment, a single chip microcomputer or a computer is used for driving to generate a pattern. A small led screen may also be substituted.

The small horn loudspeaker provided by the embodiment of the invention can be purchased in the market. In the experiment, a single chip microcomputer or a computer is used for driving to generate specific waveform sound. A buzzer can also be replaced.

The camera of the embodiment of the invention can be a common visible light camera, can be a USB Video Class camera based on an AC6102_ V2 development board, and can be purchased and obtained in the market. And video data are recorded in the experiment and transmitted to a single chip microcomputer or a computer. An infrared camera can be replaced.

The camera is fixed on the cover through glue, and a signal wire of the camera is communicated with an external singlechip or computer through a central hole 10 of the cover plate, as shown in fig. 4. And image data in the experiment is transmitted to an external singlechip or computer in real time.

The control module is an external singlechip or a computer. The single chip microcomputer can adopt a common raspberry singlechip microcomputer, and needs to be connected with a computer before an experiment to program the computer to set an operating program. The computer is loaded with corresponding control software. The control software may be adapted to the system that supports driving such hardware, such as window, android, linux, or ios.

The single chip microcomputer of the embodiment of the invention is a raspberry singlechip microcomputer and can be purchased in the market. Drive LCD screen and speaker in the experiment to record camera data, can also replace for the singlechip of other brands.

In order to better utilize the device, the invention also provides a novel animal cognitive behavior testing method which can effectively evaluate the short-term memory, the space positioning and the response to complex stimulation of the animal. Such tests cannot be performed using other multi-arm maze training devices or animal testing boxes.

In some embodiments of the invention, the animal cognitive behavioral testing apparatus is used as follows: when the experiment is started, food rewards can be firstly placed at the outward tail ends of any maze arms; then the integrated partition plates are placed according to the requirements of the integrated partition plates and clamped in the clamping grooves of the labyrinth arms; the signal wire is led out from the notch position of the round cover and is connected to a singlechip or a computer with a control program; small animals, such as mice, are then placed in the center of the maze and covered with lids. At the moment, a liquid crystal screen or a loudspeaker on the partition board is controlled by a single chip microcomputer or a program on a computer to generate complex image or sound stimulation, and the stimulation on different partition boards can be independently controlled respectively. When a mouse has exploration behaviors or selects one arm to enter for eating, video data is transmitted to the single chip microcomputer or the computer in real time through the camera, and a program judges whether to drive the liquid crystal screen or the loudspeaker on the control partition plate to change the stimulation mode, so that the behaviors and cognition of the mouse are influenced. In the whole experiment process, the mouse is in a relatively closed box space, so that the interference of the external environment on the mouse is avoided.

Based on the device, the animal cognitive behavior testing method in some embodiments of the invention comprises:

(1) an adaptation stage: mice were placed in the apparatus without any food and stimulation prior to the experiment and were removed half an hour after they had been explored.

(2) A training stage: food was spread on one of the arms and was only found when the mouse entered the end of the arm. At this point, static image stimuli are added, such as a sphere, a square, a cone, and a round bar, respectively, on the liquid crystal screen. Meanwhile, the four loudspeakers are respectively made to emit sounds in different frequency bands, such as 10Hz, 30Hz, 50Hz and 70 Hz. Mice were placed in the maze center and when they explored for 1 minute or found food, they were replaced in the center and repeated three times.

(3) A testing phase comprising one or more of the following tests:

1. when the mouse starts to search from the center, the image data recorded by the camera drives the program, the sound of the four loudspeakers is closed, or the frequency of the sound production is exchanged among the loudspeakers, and the image stimulation is unchanged. The computer or the singlechip records and counts according to the transmitted image data, and watches the short-time visual memory and visual positioning conditions of the mouse;

2. when the mouse starts to search from the center, the image data recorded by the camera drives the program, the four liquid crystal screen images are closed, or the liquid crystal screens exchange images with each other, and the sound stimulation is not changed. The computer or the singlechip records and counts according to the transmitted image data, and watches the short-time course auditory memory and auditory positioning conditions of the mouse;

3. when the mouse starts to search from the center, the image data recorded by the camera drives the program to periodically change the four liquid crystal screen images (switch in the original images) or periodically change the four loudspeaker sounds (switch in the original frequencies). And the computer or the singlechip records and counts according to the transmitted image data, and the response condition of the mouse to the complexity and the periodic stimulation is observed.

(4) And (5) finishing: and taking out the experimental mouse, copying the data of the singlechip or the computer, cleaning the device and returning. Finally, a series of data such as the times of entering different arms of the mouse in the test stage, the time of exploring food and the like are obtained, and then the data are analyzed according to the experiment requirements.

The invention can be applied to small laboratory animals (e.g. rodents) such as: rats, mice, guinea pigs, etc., can also be used to detect large animal behaviors, such as cats, dogs, monkeys, etc., by scaling up.

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An animal cognitive behavioral testing method employing an animal cognitive behavioral testing apparatus based on multi-modal stimulation, the apparatus comprising: the multi-arm labyrinth comprises a plurality of channels serving as labyrinth arms and extending to different directions from a central area of the labyrinth, wherein inlets of the plurality of channels are respectively provided with an independent display screen and an independent sound source, and the tail ends of the channels are closed;

the controller is connected with the display screen, the sound source and the camera device and is used for controlling the image displayed by the display screen and the sound emitted by the sound source and recording and counting image data obtained by the camera device;

wherein each display screen is capable of independently displaying different images under the control of the controller;

the sound wave frequency, sound wave shape and/or sound volume of each sound source can be independently changed under the control of the controller;

the method comprises the following steps:

(1) a training stage: placing food at the tail end of one maze arm of the multi-arm maze, statically displaying different images on each display screen and making each sound source emit different sounds, placing an animal at the center of the multi-arm maze, and when the animal searches for a preset time or finds the food, placing the animal back to the center of the multi-arm maze, and repeating the training for multiple times;

2. The animal cognitive behavior testing method according to claim 1, wherein the testing stage comprises the steps of placing the animal in the center of the multi-arm maze, recording and counting image data obtained by the camera device, and analyzing the short-term visual memory and visual positioning ability of the animal under the condition that sound sources are turned off or sound sources exchange sound with each other while images displayed by display screens are kept unchanged;

3. The animal cognitive behavioral testing method according to claim 1 or 2, wherein the method further comprises an adaptation phase comprising placing the animal in a multi-arm maze and allowing it to explore for a predetermined time without food, image and sound stimuli.

4. A method for testing the cognitive behaviour of an animal according to claim 1 or 2, wherein said animal is a rodent, cat, dog or monkey.

5. The method for testing the cognitive performance of an animal according to claim 1, wherein the number of training is 3 to 5.

6. A method as claimed in claim 3, wherein the predetermined time is 20min-1 h.

7. A method as claimed in claim 3, wherein the predetermined time is 30-40 min.

8. The animal cognitive behavior testing method according to claim 1, wherein the animal cognitive behavior testing device further comprises an integrated partition plate, the integrated partition plate is provided at an inlet of the passage, and the display screen and the sound source are provided on the integrated partition plate.

9. The animal cognitive behavior testing method according to claim 1, wherein the animal cognitive behavior testing device further comprises a hollow shell, the multi-arm labyrinth is arranged in the hollow shell, a cover plate is arranged on the hollow shell, and the image pickup device is arranged below the cover plate.

10. The animal cognitive behavior testing method of claim 1, wherein the display screen is a liquid crystal display screen or an LED display screen.

11. The animal cognitive behavior testing method according to claim 1, wherein the sound source is a speaker or a buzzer.

12. The animal cognitive behavior testing method according to claim 1, wherein the camera is a visible light camera or an infrared camera.

13. The animal cognitive behavioral testing method of claim 1, wherein the multi-arm maze has no less than 4 passages.

14. The animal cognitive behavioral testing method of claim 1, wherein the number of channels of the multi-arm labyrinth is 6-8.