JP4781799B2 - Electrical stimulator - Google Patents

Description

  The present invention relates to an electrical stimulation device that stimulates an organ that responds to stimulation including a vestibular sensation and muscles by passing a weak current.

2. Description of the Related Art Conventionally, as described in Patent Document 1, a body guidance device using electrical stimulation to a vestibular sensation which is a receptor for balance sensation is known. The induction of walking by such electrical stimulation is as follows.
As shown in FIG. 21, a skin surface electrode 44a is placed behind the left ear of the wearer 1 and a skin surface electrode 44b is placed behind the right ear. When a weak direct current is applied, a sense of acceleration can be generated in the vestibular sense of the wearer 1 toward the anode side. That is, the subjective gravity direction of the wearer 1 is inclined, and the center of gravity of the wearer 1 fluctuates according to the direction and strength of the current, and the body swims to the left or right. Since there is no irritation to the skin, the wearer 1 notices after his body moves.

  In this way, by generating a sense of acceleration in the left-right direction, it is possible to cause an inclination in the sense of the vertical direction that is the origin of the standing-up motion, and thus the standing posture of the wearer 1 is intended to be intended by the person. It tilts to the anode side regardless of the response. When this inclination is generated during walking, the walking direction of the wearer 1 is bent toward the anode side as shown in FIG. That is, as shown in FIG. 22, when a current is passed using the skin surface electrode 44a placed behind the left ear of the wearer 1 as an anode and the skin surface electrode 44b placed behind the right ear as a cathode, the wearer 1 The left side of the anode is bent and walked, and a current is passed through the skin surface electrode 44a placed behind the left ear of the wearer 1 as a cathode and the skin surface electrode 44b placed behind the right ear as an anode. Then, the wearer 1 turns and walks in the right direction on the anode side.

  FIG. 23 shows an example in which the walking of the wearer 1 of the walking guidance device is guided as described above. The graph of FIG. 23 is obtained by plotting the position of the waist of a human walking as if walking in the direction of the z-axis in FIG. 22 from above as a walking locus. The horizontal axis of the graph represents the amount of movement in the z-axis direction of FIG. 22, that is, the forward direction, and the vertical axis represents the amount of movement in the x-axis direction of FIG. The amount of current is a positive value when the skin surface electrode 44a placed behind the left ear of the wearer 1 is an anode, and the skin surface electrode 44b placed behind the right ear is a cathode, and the opposite case is a negative value. The walking locus of the wearer 1 is plotted for each current amount. Each mark represents a position every 0.5 seconds, and electrical stimulation started from the position of 0 on the horizontal axis.

According to FIG. 23, as the current amount increases toward the plus side, the leftward direction increases, and as the current amount increases toward the negative side, the rightward direction increases. This shows that the left and right acceleration feeling can be controlled. Using this phenomenon, the wearer 1 can be guided with high reproducibility without forced external force.
That is, as shown in FIG. 21, skin surface electrodes 44a and 44b having a diameter of about 3 to 5 cm are installed (for example, pasted) on the milky protrusions at the rear of both ears, and as described above, this skin By flowing a current of several mA between the surface electrodes, acceleration toward the anode side is generated with respect to the vestibular sensation. (For example, see Patent Document 1)
JP 2004-254790 A

Since the conventional body guidance apparatus as described above causes a current to flow between the skin surface electrodes attached to the skin, electrical stimulation resulting from the voltage value applied to the skin electrodes is applied to the skin.
Therefore, the conventional body guidance device needs to suppress the painful stimulation given to the skin from the skin surface electrode in order to make it easy for the user to use. For this reason, it is necessary to reduce the current density per area of the skin surface electrode that is in close contact with the skin, and a structure in which the current density is reduced by increasing the electrode area generally allows a large area skin surface electrode to be formed. Used for stimulation current. Here, the large area refers to the current density (current per unit area) that receives sensory stimulation in the area where the skin surface electrode is in close contact when the area of the surface that is in close contact with the skin is subjected to body induction and current is applied. The value of the area that is less than (quantity) is shown.

However, in the conventional body guidance device, as described above, the large area electrode increases the amount of leakage current to other than the target site, and the current for stimulating the vestibular sensation decreases. In order to increase the amount of current, the amount of current used for the treatment must be increased, and there is an adverse effect of causing various unintended electrical stimulation effects on the skin.
The present invention has been made in consideration of the above circumstances, and in order to effectively give a current to the vestibular sensation with respect to the skin electrode that injects the current of the vestibular stimulation, the structure of the electrode to be attached around the ear and The body guidance device and skin surface for obtaining a stimulating effect on a high vestibular sensation even when the area of close contact with the skin is reduced compared to the conventional case by reducing the skin irritation compared to the conventional example by devising the arrangement The object is to realize an electrode.

  An electrical stimulation device according to the present invention includes a current command value generation unit that generates a sensory stimulation current that stimulates a vestibular sensation, an electrical stimulation unit that outputs the sensory stimulation current, and a current path of the sensory stimulation current mainly in a vestibular organ. An electrical stimulation device comprising a sensory stimulation electrode to be mounted in the vicinity of a hole in the skull, which is a region included in the above.

  In the electrical stimulation device of the present invention, the sensory stimulation electrode has a shape that sandwiches the tragus in the vicinity of the external auditory canal, which is a hole in the skull, and the close contact portion with the skin is formed of a conductive gel.

  The electrical stimulation device of the present invention has a shape in which the sensory stimulation electrode is in close contact with the auricular base near the external auditory canal, which is a hole in the skull, and the vicinity thereof, and the close contact with the skin is formed of a conductive gel. The point contact portion is formed of an insulator.

  The electrical stimulation device according to the present invention is characterized in that the sensory stimulation electrode is formed in a modern part of the glasses.

  The electrical stimulation device according to the present invention is characterized in that the sensory stimulation electrode is formed on a vine portion that is in close contact with the auricle base of the earphone.

  The electrical stimulation device according to the present invention is characterized in that the sensory stimulation electrode is made of a deformable material corresponding to the curvature of each user's auricle base.

The electrical stimulation device of the present invention is characterized in that the sensory stimulation electrode has a clip shape that sandwiches an earlobe near the ear canal, which is a hole in a skull, and a close contact portion with the skin is formed of a conductive gel.
The electrical stimulation device according to the present invention is characterized in that the sensory stimulation electrode has an earphone shape inserted into the ear canal, which is a hole in the skull, and the close contact portion with the skin is formed of a conductive gel.

An electrical stimulation device according to the present invention includes a current command value generation unit that generates a sensory stimulation current that stimulates a vestibular sensation, an electrical stimulation unit that outputs the sensory stimulation current, and a current path of the sensory stimulation current mainly in a vestibular organ. And a palatal sensory stimulation electrode to be mounted in the palate.
The electrical stimulation device of the present invention is characterized in that the intra-palal sensory stimulation electrode is provided as a counter electrode of the sensory stimulation electrode described above.

  An electrical stimulation device according to the present invention includes a current command value generation unit that generates a sensory stimulation current that stimulates a vestibular sensation, an electrical stimulation unit that outputs the sensory stimulation current, and a current path of the sensory stimulation current mainly in a vestibular organ. A sensory stimulation electrode to be mounted in the vicinity of the ear canal, a sensory stimulation electrode to be mounted in the palate, wherein the current path of the sensory stimulation current mainly includes a vestibular organ, and the sensory stimulation current. And a forehead sensory stimulation electrode attached in the vicinity of the orbit, in which the current path is a region mainly including a vestibular organ.

According to the present invention, an electrode shape that is easy for the wearer to wear is realized so that the current path of the sensory stimulation current is a region mainly including the vestibular organ and can be worn near the hole of the skull. It is possible to reduce the leakage current that flows outside the path through the vestibular organ and to stimulate the vestibular sensation accurately.
That is, according to the present invention, it is possible to give stimulation to a vestibular sensation equal to or higher than that of the conventional art with less current compared to the conventional example by using the vicinity of the ear canal as a stimulation site compared to the conventional case. It is possible to suppress the sensory stimulation current to an efficient amount of current, and skin irritation can be reduced.

In addition, according to the present invention, it is possible to stimulate the vestibular sensation equal to or higher than that of the conventional case with less current compared to the conventional example by using the vicinity of the ear canal as a stimulation site compared to the conventional case. By being able to do so, it is possible to make a smaller contact area, that is, a small electrode compared to the conventional case, to further limit the stimulation site closer to the ear canal, and to reduce the leakage current flowing elsewhere An effect can be obtained.
For this reason, all of the electrodes (sensory stimulation electrodes) in the present invention are configured to be mounted on the tragus or the auricle portion, which is closer to the ear canal mouth, with respect to the conventional posterior mastoid process.

The above-mentioned effect is: “Stimulation closer to the ear canal (the ear canal) in order to efficiently avoid dispersion of current due to leakage current, etc., assuming a current path through the skull hole as a current path that provides electrical stimulation to the vestibular organ It is obtained by attaching an electrode to the site.
The technical idea that is the basis of the design guideline for obtaining this effect will be described in detail in “Best Mode for Carrying Out the Invention” described later.

<Basic concept of the present invention>
The basic technical idea of the present invention is to assume a current path through the hole in the skull as a current path that brings electrical stimulation to the vestibular organ, and in order to efficiently avoid current distribution due to leakage current, etc. ) Explain the technical considerations of “attaching electrodes to the stimulation site closer to”.
FIG. 1 is a conceptual diagram showing an electrode arrangement site in the conventional research. FIG. 1A is a conceptual diagram showing the head of a user wearing a skin surface electrode from the front, back, left and right, and FIG. 1B is a side view as viewed from the left side (Side View). It is a conceptual diagram which shows an arrangement | positioning site | part, FIG.1 (c) is a conceptual diagram which shows the electrode arrangement | positioning site | part by which an electrode is arrange | positioned, (Top View) seen from the parietal direction. Here, as shown in FIG. 1B, an electrode arrangement site is provided on a line G having an angle of 34 ° counterclockwise with respect to the horizontal axis D in the figure. Further, as shown in FIG. 1C, the head cross section is circular, and the electrode arrangement sites E0, E1, E2, E3, E4, E5 is provided, and a total of six electrode arrangement sites are set.

Here, a table of the distance between each electrode arrangement site and the actually measured DC resistance value is shown in the table of FIG. 2, and a graph in which the DC resistance values are grouped by the angle θ is shown in FIG. In the table of FIG. 2, the resistance Rij indicates the direct current resistance value between the electrode placement portions Ei and Ej, and the distance D01 indicates the distance between the electrode placement portions Ei and Ej. In FIG. 3, the horizontal axis indicates the group angle θ, where N = 1 (1 × π / 6), N = 2 (2 × π / 6), and N = 3 (3 × π / 6).
Further, assuming that the human skull is an insulator and the skin on the outer surface of the skull is a spherical shell-like resistor, the relationship between the distance and the DC resistance value is expressed by a theoretical formula (1), ( When solved by equations (2) and (3), the correspondence shown in the graph of FIG. 4 is obtained. In FIG. 4, the vertical axis represents resistance, and the horizontal axis represents the angle θ, that is, the interval at which the predicted resistance value was measured (the distance increases as the angle θ increases).

Originally, in the case of a spherical shell-shaped resistor on the insulator surface, as shown in FIG. 4, the resistance value increases as the distance increases.
However, the DC resistance value measured by the graph shown in FIG. 3 does not change monotonously as the predicted resistance value according to the change in distance, and in particular, between the electrode arrangement parts of the electrode arrangement parts E0, E2 and E4. It can be clearly seen that the direct current resistance values, that is, the resistance values R02, R24, and R40 are lower than the other resistance values.

From the above results, as shown in FIG. 5, it can be estimated that there are current paths different from the spherical shell resistors, that is, resistors R02I, R24I, and R40I, between the electrode arrangement portions E0, E2, and E4. Here, it can be estimated that each of the resistors R02I, R24I, and R40I is a resistance in a current path in the cranium via the orbital hole and the ear canal.
In the above-described current path penetrating the skull, it is considered that the current flowing through this current path stimulates the vestibular organ in the skull, thereby improving the efficiency of the vestibular stimulation.

Accordingly, in order to minimize the dispersion (leakage current) of the sensory stimulation current flowing through the ear canal, it is desirable to set the position closer to the inner ear from the ear hole as the electrode placement site and install the electrode It turns out theoretically.
That is, unless an electrode placement site is set in the vicinity of a hole (orbital hole, ear canal, etc.) that opens to the skull, which is the input end and output end of the current path that penetrates the skull, The current that diffuses into the spherical shell-shaped resistor exists as a leakage current, and the sensory stimulation current cannot be efficiently applied to the vestibular organ, resulting in a wasteful current.

  In the conventional research, as an analysis described in this specification, only a high-frequency component such as an electroencephalogram capable of penetrating an insulator has been made. Therefore, when detecting high-frequency components such as brain waves, the effect of the skull hole is out of consideration, and the DC component including the current path that penetrates the inside of the skull through the ear canal (ear hole) and the eye socket No analysis has been made. Therefore, no knowledge has been reported regarding the stimulation efficiency of electrode arrangement based on the viewpoint of the present invention using direct current. Actually, the sensory stimulation current (stimulation current) passing through the current path in the cranium estimated in the present invention stimulates the vestibular organ in this current path, and thus it is considered that vestibular electrical stimulation is established. .

Next, a geometric calculation model and a theoretical formula in this model are shown. In FIG. 6, the resistance value between the electrode positions was calculated according to the position according to the following equations (1), (2), and (3), with the human head being spherical.
In the following formulas (1) to (3), the radius of head R is R = 0.1 [m], and the radius of electrodes Re is Re = 0.015 [m]. The conductivity of human skin σ = 0.2 [S], angle θ = θ / 3 [rad], The equivalent thickness of the skin as a conductor Skin as conductor) T was set to T = 0.003 [m], and the resistance value between each electrode position was calculated.

<Electric stimulation device>
Next, an embodiment of the present invention will be described with reference to the drawings, in which a sensory stimulation current is supplied to an electrode attached to an electrode arrangement site set according to the concept described above. FIG. 7 is a block diagram showing the configuration of the electrical stimulation apparatus 100 in this embodiment. The current change amount control unit 20 uses the frequency as a reference for the problem that the timing of stimulus presentation is greatly delayed in the conventional low-pass filter processing in order to reduce skin pain sensation when applying sensory stimulation current. Instead of processing, the processing of suppressing the current change amount per unit time to a certain level or less reduces the time delay until the stimulation is effective without causing skin pain sensation. The configuration of the current change amount control unit 20 illustrated in FIG. 7 is an example, and is not limited to this configuration.

  The constant value output unit 21 of the current change amount control unit 20 outputs a constant voltage. The gain adjuster 22 is provided with a variable resistor that adjusts the amplification factor, and outputs and increases or decreases the input voltage according to the amplification factor. Since this voltage is integrated by the integrator 24 and used as a value indicating the amount of current, the voltage output from the gain adjuster 22 and input to the integrator 24 becomes a value indicating the amount of current change per unit time. That is, the current change amount can be controlled by adjusting the gain of the gain adjuster 22. In the graph of FIG. 8, since the current change amount of the rising waveform at the stimulus input start time t0 is the portion where the change in the current amount per unit time that does not stimulate skin pain is the largest, the voltage output from the gain adjuster 22 is the current. The gain of the gain adjuster 22 is set so that the value corresponds to the amount of change. In FIG. 8, the horizontal axis represents time, and the vertical axis represents the current value.

  The comparator 26 compares the voltage output from the current command value output unit 10 with the voltage output from the integrator 24, and outputs a high level or low level voltage. For example, when the voltage output from the integrator 24 is smaller than the voltage output from the current command value output unit 10, the comparator 26 outputs a high level voltage, and otherwise outputs a low level voltage. The switch 23 closes the switch 23 when a high level voltage is input from the comparator 26 and inputs the output voltage of the gain adjuster 22 to the integrator 24. When the low level voltage is input, the switch 23 switches the switch 23. And the output voltage of the gain adjuster 22 is not input to the integrator 24. The integrator 24 integrates and outputs the voltage output from the gain adjuster 22. That is, the output voltage of the integrator 24 rises in proportion to time, and when it rises to a value equal to the current command value, the value is maintained thereafter.

  The gain adjuster 25 is provided with a variable resistor that adjusts the amplification factor, and outputs and increases or decreases the input voltage according to the amplification factor. The voltage obtained by increasing or decreasing the output voltage of the integrator 24 maintained at a value equal to the current command value according to the gain of the gain adjuster 25 is input to the constant current generation / control unit 40 as a value indicating the steady target current amount. . That is, the steady target current amount can be controlled by adjusting the gain of the gain adjuster 25.

  The current change amount control unit 20 controls the steady target current amount and the current change amount per unit time with the above-described configuration. Further, the constant current generation / control unit 40 is configured in the same manner as in the prior art, and measures the actual amount of current flowing so as to achieve the steady target current amount and the current change amount input from the current change amount control unit 20. Control the current supply.

  The current waveform by the electrical stimulation device 100 described above is indicated by a broken line in the graph of FIG. This broken line indicates a current value input to the wearer 1 via the electrode by the electrical stimulation device 100. The current change amount control unit 20 converts the voltage output by the current command value output unit 10 as a current command value into a voltage having a ramp-type time response tracking characteristic, and raises the voltage to a voltage equal to the current command value. maintain. This voltage is output by increasing / decreasing according to the gain of the gain adjuster 25, and a current corresponding to this voltage is input to the wearer 1 from the user skin electrode 44 of the constant current generation / control unit 40.

  When a current command value indicating a stimulation target current value smaller than I0 is output from the current command value output unit 10, the wearer 1 is given a weaker stimulus, and the effect is smaller than the effect produced by I0. Play. That is, when the electrical stimulation device 100 induces walking as described above, the walking can be guided small.

  In the processing by the low-pass filter of the conventional electrical stimulation apparatus, the portion with the largest change in the amount of current per unit time that does not stimulate skin pain is the rising waveform at the stimulation input start time t0. If the change in the current amount more drastically than this, that is, the time waveform of the stimulation current is represented in the graph, if it is included in the shaded portion in FIG. 8, skin pain sensation will be stimulated. Therefore, it is necessary to keep the amount of time change of the current value below a certain level. In this embodiment, by appropriately setting the gain adjuster 22, it is possible to control the current with the maximum amount of change that is a limit value that does not always stimulate the skin pain, and without stimulating the skin pain. The stimulation target current value I0 can be reached in the shortest time from t0 to t1.

  Next, another configuration example of the electrical stimulation device will be described. Unlike the configuration in which the current command value output from the current command value output unit 10 is directly input to the constant current generation / control unit 40, the electrical stimulation device 110 in FIG. As a result, it is possible to set an appropriate steady target current amount and current change amount per unit time from the outside of the electrical stimulation device 110 for each wearer 1, and to reduce skin pain sensation that is not desired to be applied.

  The electrical stimulation device 110 includes the above-described current command value output unit 10, current change amount control unit 20, and constant current generation / control unit 40. The user stimulus adjustment knob 27 includes a knob for changing a resistance value of a variable resistor used for current change amount adjustment provided in the gain adjuster 22 (FIG. 7) in the current change amount control unit 20, and a gain adjuster 25. It is comprised from the knob for changing the resistance value of the variable resistor used for the electric current amount adjustment provided in (FIG. 7). In FIG. 7, the user skin electrode 44 included in the constant current generation / control unit 40 is not included in the constant current generation / control unit 40 in FIG.

  The electrical stimulation device 110 further includes an adjustment signal generator 50 and an operation / adjustment changeover switch 60 within a broken line. The adjustment signal generator 50 outputs a positive or negative maximum current command value. The operation / adjustment changeover switch 60 is a toggle switch. When the common contact c is connected to the contact a, the output voltage of the current command value output unit 10 is input to the current change amount control unit 20, and the common contact c is connected to the contact b. The output voltage of the adjustment signal generator 50 is input to the current change amount control unit 20.

  The operation of the electrical stimulation device 110 is as follows. The wearer 1 installs the skin surface electrodes 44a and 44b constituting the user skin electrode 44 behind the left ear and the right ear, respectively, and connects the common contact c of the operation / adjustment switch 60 to the contact b. Then, a value equal to the maximum positive and negative current command value output from the current command value output unit 10 is output from the adjustment signal generator 50 to the current change amount control unit 20. A current amount corresponding to the voltage output by the current change amount control unit 20 is input from the constant current generation / control unit 40 to the wearer 1 through the user skin electrode 44. The positive / negative switching of the maximum current command value output from the adjustment signal generator 50 may be configured to be manually switched by the wearer 1, and the current value input to the wearer 1 is a graph in FIG. 2. It may be configured to automatically and repeatedly switch between positive and negative at a time interval until it increases to become a constant value as shown by a broken line, that is, a time interval longer than the time from t0 to t1.

  At this time, if the wearer 1 feels a skin pain sensation, the current provided in the gain adjuster 22 (FIG. 7) is operated so as to obtain an appropriate skin pain sensation by operating the user stimulus adjustment knob 27. The resistance value of the variable resistor used for the change amount adjustment and the resistance value of the variable resistor used for the current amount adjustment provided in the gain adjuster 25 (FIG. 7) are changed. Thereby, the current change amount control unit 20 uses the current command value output from the current command value output unit 10 as the lamp response corresponding to the steady target current amount appropriate for each wearer 1 and the current change amount per unit time. And output to the constant current generation / control unit 40. When the wearer 1 adjusts the steady target current amount and the current change amount per unit time to an appropriate value in this way, and then connects the common contact c of the operation / adjustment changeover switch 60 to the contact a, the current command value output unit The current command value output from 10 is input to the current change amount control unit 20. By such reference work, it is possible to optimally reduce skin pain sensation in vestibular electrical stimulation or the like, and to prevent a delay in response until the electrical stimulation is effective.

  In the above description, the wearer 1 manually sets the steady target current amount and the current change amount per unit time. However, it may be automatically set according to individual differences and environmental differences. In this method, the energization resistance of the user skin electrode 44 is measured in a short time before the stimulus is actually applied, and a preferable steady target current amount and a current change amount per unit time are estimated and automatically set based on the measurement result. Is.

  An example of the configuration and the operation for performing automatic setting as described above is as follows, but is not limited thereto. Here, the configuration of the current change amount control unit 20 (FIG. 1) of the electrical stimulation device 100 described above is added as follows. The current change amount control unit 20 further includes an energization resistance measurement unit, a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory). The gain adjuster 22 and the gain adjuster 25 are connected to the CPU and set the amplification factor to a value instructed by the CPU. The energization resistance measuring unit is connected to the user skin electrode 44, and when an instruction for measuring the energization resistance is input from the CPU, the energization resistance of the user skin electrode 44 is measured and the measured value is output to the CPU.

  The CPU controls the current-carrying resistance measurement unit as described above and the gains of the gain adjuster 22 and the gain adjuster 25 according to the control program stored in the ROM. The RAM stores data in CPU processing. The ROM stores in advance a CPU control program and a table used for setting a preferable steady target current amount and a current change amount per unit time for the value of the energization resistance.

The items in the table include the value of the energization resistance, the gain set in the gain adjuster 25, and the gain set in the gain adjuster 22. First, a reference energization resistance value and a preferable current change amount per unit time corresponding thereto are determined. A plurality of energization resistance values are prepared.
Then, for each energization resistance value, a ratio α to the reference energization resistance value is calculated, a value of m times α and a value of 1 / n of α are calculated, and each value is calculated. As the gain set in the gain adjuster 25 and the gain set in the gain adjuster 22, a table is created in association with the value of the energization resistance. Here, m and n are positive numbers smaller than 1. The voltage output from the constant value output unit 21 is set to a voltage corresponding to a preferable current change amount per unit time corresponding to the value of the energization resistance serving as the reference.

  The CPU of the current change amount control unit 20 described above operates as follows. First, a measurement instruction for the conduction resistance is output to the conduction resistance measurement unit, and the measurement value is acquired and stored in the RAM. Next, in the table stored in the ROM in advance, the value of the energization resistance equal to the measurement value stored in the RAM is specified, and when there is no equivalent, the closest energization resistance value is specified, and α corresponding to this is multiplied by the m-th power And 1 / nth power of α are acquired. These values are set as the gain of the gain adjuster 25 and the gain of the gain adjuster 22, respectively. Then, a current amount corresponding to a value obtained by multiplying the current command value by α to the mth power is a steady target current amount, and a current amount corresponding to a value obtained by multiplying the value output by the constant value output unit 21 by 1 / αth power. Is the amount of current change per unit time.

<Skin surface electrode worn near the ear canal>
Hereinafter, the structure of the skin surface electrode (electrode) attached near the hole of the skull and the vicinity of the ear canal according to the present invention will be described. By attaching skin surface electrodes attached to both ears in the vicinity of the ear canal, the ear canal, the inner ear canal, the vestibular organ, the other inner ear canal, and the other ear canal as a current path, laterally (with the face front) Since the current flows through the vestibular organ, a sense of acceleration to the left and right is given. That is, by attaching to both the left and right ears, each becomes a counter electrode, and a sense of left and right acceleration can be obtained, and as will be described later, each electrode to be mounted in the palate and on the forehead (near the orbit) is also provided with a counter electrode. Can be configured.
A. Trabeculae type electrode The skin surface electrode shown in FIG. 10 to be attached to the tragus in the auricle of the head will be described.
For example, the tragus sandwiching type electrode has a structure as shown in FIG. 11, and a conductive rubber layer 52 is formed on the upper portion of the base 51 made of a hard insulating material or the like, and this conductive rubber layer 52 is further formed. A conductive gel layer 53 is formed on the top. That is, the base portion 51, the conductive rubber layer 52, and the conductive gel layer 53 constitute fixing portions 55A and 55B that sandwich the tragus.

  The fixing portions 55A and 55B are connected to the spring mechanism portion 56, and the fixing portion 55A is urged by the spring mechanism portion 56 in the direction of the arrow P1, and the fixing portion 55B is in the direction of the arrow P2, that is, in the direction in which the facing surface approaches. Has been. At this time, the fixing portion 55A and the fixing portion 55B are connected to the spring mechanism portion 56 so that the conductive gel layer 53 faces each other. The lever 57 is operated so as to be close to each other, the interval between the fixing portion 55A and the fixing portion 55B biased by the spring mechanism portion 56 is widened, and the tragus is sandwiched and attached. In the mounted state, a sensory stimulation current is applied from the electrical stimulation device 100 to the tragus via a cable.

The above-mentioned skin surface electrode attached to the tragus can efficiently send an interval stimulation current to the current path inside the cranium in terms of the proximity of the electrode placement site to the inner ear (ie, the external auditory canal). As compared with other electrode configurations of the present invention, the largest stimulation gain can be obtained.
Although it seems that the general user is not used to the act of inserting the fixing part into the ear canal and pinching the tragus, it seems that there is a resistance to wearing, but the force that biases the fixing part of the spring mechanism part 53 That is, by adjusting the pressure sandwiched between the fixing portions 55A and 55B, there is no sense of incongruity even when used for a long time, and it can be easily mounted.

As the characteristics of the skin surface electrode, compared to the mounting of the electrode placement site of the skin surface electrodes 44a and 44b shown in FIG. 21, since the sensory stimulation current applied flows through the current path inside the cranium efficiently because it is close to the ear canal, Leakage current diffusing into the spherical shell resistor (integrated value of the current diffused into the spherical shell resistor) is greatly reduced (about 1/80; estimated value from equations (1) to (3)) The area of the close contact portion of the electrode can be reduced to 1/16.
As a result of confirming this tragus pin type electrode with a plurality of users, even if the area is 1/16 compared with the conventional skin surface electrode shown in FIG. 21, the equivalent gain is 3 to 10 times, almost 5 times. It was found that the above sensory stimulation can be obtained.

B. Ear ring type electrode The ear ring type electrode has a structure in which the pinna is closely attached to the pinna base shown in FIG.
FIG. 13 is a conceptual diagram showing the structure of a ring-shaped electrode for ear. A conductive rubber 62 is wound around a rod-shaped insulating base 61, and a conductive gel layer 63 is formed on the conductive rubber 62. The base material 61 is insulative as described above, and is made of a deformable material that can be curved and matched to the shape of each user's auricle. Deform and fix to pinna. In addition, the base material 61 may be deformable, and a metal rod whose shape is stable in a deformed state may be coated with an insulating material as a layer.

In order to increase the contact area, it is also conceivable to provide a conductive gel layer on the fixing portions 61A and 61B. However, when fixing to the auricle, there is a high possibility of point contact, and the current density at the point contact part becomes high and skin pain sensation is received, so the fixing parts 61A and 61B need to be in an insulated state. It is. In the worn state, a sensory stimulation current is applied from the electrical stimulation device 100 to the auricle base via a cable.
According to the structure described above, the base material 61 is deformed in accordance with the shape of each individual's pinna and is kept in contact with the skin of the base of the pinna. Since the material 61 is in a curved state corresponding to the shape of the auricle by the adjustment, the stability after the adjustment is very high.

In addition, since the conductive gel layer 63 has the shape of the auricle base, the adhesion to the skin is high, the contact area with the skin is large, and it is slightly farther from the external auditory canal than the tragus. A necessary amount of current can be obtained.
In addition, it is considered that the structure is suitable for widespread use because it hardly disturbs even after wearing, no extra pressure is applied by pressing, and there is no sense of discomfort and does not inhibit blood circulation.

As for the characteristics of the skin surface electrode, the sensory stimulation current applied is similar to the trabecular electrode of FIG. 11 because it is closer to the external auditory canal compared to the attachment of the electrode placement site of the skin surface electrodes 44a and 44b shown in FIG. Efficiently flows through the current path inside the cranium, and the leakage current that diffuses into the spherical shell resistor (the integrated value of the current diffused into the spherical shell resistor) decreases (about 1/6; (1) to (Estimated value from equation (3)), and the area of the close contact portion of the electrode can be reduced to ½.
As a result of confirming this tragus pin type electrode by a plurality of users, even if the area is ½ compared with the conventional skin surface electrode shown in FIG. Was found to be obtained.

C. Spectacle-ear-hanging part-type electrode This spectacle-ear-hanging part-type electrode is basically formed by applying the above-mentioned B-ear-ring-type electrode to the vine part of the spectacles. As shown in FIG. 14, a conductive rubber 71 is wound around a vine portion of eyeglasses in contact with the auricle base, and a conductive gel layer 72 is formed on the conductive comb 71.
In addition, it is necessary that the vine portion other than the intimate contact with the auricle base portion is configured to maintain insulation so as not to make point contact and give skin pain sensation.
Since the characteristics of this skin surface electrode are the same as those of the above-mentioned B ring-shaped electrode, description thereof is omitted.
Since the glasses themselves are the property of a personal individual, they are deformed and adjusted so as to be in close contact with the base of the auricle without adjusting the base material, i.e., the vine, as in the above-described ring-shaped electrode for the ear. Therefore, it can be said that it is a practical structure. While wearing the glasses, a sensory stimulation current is applied from the electrical stimulation device 100 to the auricle base via a cable.

D. Earphone type electrode This earphone type electrode is basically applied to the part of the fixing part 80 for fixing the earphone to the auricle, which is in contact with the auricular base, of the B earring type electrode. is there. As shown in FIG. 15, a conductive rubber 81 is wound around a region of the fixing portion 80 that contacts the auricle base and is in contact with the auricle base, and a conductive gel layer 82 is formed on the conductive rubber 81.
In addition, as in the case of B and C, the vine portion other than the intimate contact with the auricle base portion needs to be configured to maintain insulation so as not to make point contact and give skin pain sensation.
Since the characteristics of this skin surface electrode are the same as those of the above-mentioned B ring-shaped electrode, description thereof is omitted.

In addition, since the existing wearing method for listening to music is applied, there is little resistance to wearing by the user.
However, on the other hand, since the adjustment and deformation of the fixing portion 80 are restricted to some degree of freedom, the fixing portion 80 needs to be formed of a deformable material.
In a state where the earphone is worn, a sensory stimulation current is applied from the electrical stimulation device 100 to the auricle base via a cable.

E. Earlobe pinching electrode This earlobe pinching electrode is obtained by applying the tragus pinching electrode of FIG. 11 to the earlobe (FIG. 10), and is slightly separated from the ear canal. For this reason, since the leakage current increases, it is necessary to flow the sensory stimulation current more than the A electrode, and the area of the fixing portion 55A and 55B that is in close contact with the skin is the same as that of the A tragus sandwiched electrode. It is necessary to make it larger in comparison.
In addition, since the earlobe is a site that is known to have the least painful nerves in the human body, the current density can be increased as compared with the case where it is attached to the tragus.

Since the inside of the earlobe is almost fat, the earlobe itself can be easily deformed. By utilizing this characteristic, the area of the contact portion of the fixing portions 55A and 55B in FIG. 11 is increased in a plane and sandwiched between the flat surfaces, so that the earlobe is stretched flat and stable contact and contact area are obtained. Can be secured.
A sensory stimulation current is applied from the electrical stimulator 100 to the earlobe via a cable with the earlobe-clamped electrode attached.

As a result of confirming this pinna pin type electrode by a plurality of users, a substantially equivalent equivalent gain is obtained even when the area is 2/3 (corresponding to both sides sandwiched) compared with the conventional skin surface electrode shown in FIG. It was found that It was found that almost equivalent sensory stimulation with a leakage current of 1/6 can be obtained.
The applied sensory stimulation current efficiently flows through the current path inside the skull, and the leakage current that diffuses into the spherical shell resistor (the integrated value of the current diffused into the spherical shell resistor) is greatly reduced (about 1). / 6; estimated value from equations (1) to (3)).

<Skin surface electrode to be worn inside the ear canal>
F. Earphone-type electrode As shown in FIG. 20, this earphone-type electrode basically has an in-ear type earphone shape, and is a protruding portion of a disc-shaped base portion 150 having a predetermined thickness made of an insulating material. The conductive gel layer electrode is formed by inserting a protruding portion 150A having a spherical shape at the tip (that is, an ear pad and using this portion as an electrode) into the ear canal. Is used in close contact with the skin in the ear canal. Here, the base 150 serves as a stopper that prevents the protruding portion 150A from being inserted into the ear canal beyond a predetermined length, and as in the case of B and C, the skin around the ear canal on the inner surface of the auricle. It is necessary to be configured so as to maintain insulation so as not to contact the skin with a point of pain and give a skin pain sensation. The base 150 is formed in a disk shape having a diameter larger than the diameter of the hole of the ear canal.

In addition, the protrusion 150A is formed by projecting the central portion of the base 150 so that conductive rubber is wrapped around the outer periphery of the protrusion 150A to form a conductive gel layer 160. It is improving.
In a state where the earphone type electricity shown in FIG. 20 is worn in the ear canal, a sensory stimulation current is applied from the electrical stimulation device 100 to the ear canal via a cable.
As a result of confirming this pinna pin type electrode with a plurality of users, it was found that an equivalent gain at least equivalent to or larger than the area in contact with the skin was obtained as compared with the conventional skin surface electrode shown in FIG.
Since the applied sensory stimulation current flows directly into the ear canal, there is almost no leakage current that diffuses into the spherical shell resistor (the integrated value of the current diffused into the spherical shell resistor). In comparison, it is estimated that the current path inside the skull flows more efficiently.

<Stimulation electrode worn in the oral cavity>
The electrode mounted in the oral cavity can apply an electrical stimulus to the vestibular organ to create a sense of acceleration in the vertical direction that has not been reported in the past.
As described above, it has been conventionally known that a sense of acceleration in the front-rear direction can be created by vestibular electrical stimulation by installing electrodes on the forehead. In this case, the current path of the sensory stimulation current in the vestibular electrical stimulation can be estimated mainly as shown in FIG. That is, as shown in FIG. 16, the vestibular organ is present at a position embedded in the skull, which is an insulator. For this reason, there are only three holes in the ear canal, inner ear canal, and ear canal as wet tissue that can pass current to the vestibular organ.

  In the vicinity of the hole in the skull, the electrodes A to E described above are installed in the vicinity of the ear canal, and the electrode F is installed in the ear canal. These electrode placement sites apply a sensory stimulus current that gives a vestibular electrical stimulus that causes the user to feel (create) a lateral acceleration in the lateral direction with the face as the front. When applied to the skin surface electrode Q2 (FIG. 17) attached to the vicinity of one ear canal and sensory stimulation current flows through the ear canal, the invading sensory stimulation current passes through the inner ear canal and passes through the vestibular organ. It is considered that the other ear canal passes through the inner ear canal to the skin surface electrode Q3 attached in the vicinity of the other ear canal (current path from arrow A to arrow B in FIG. 16).

In addition, in the forehead skin surface electrode, the stimulation of acceleration in the front-rear direction (perpendicular to the face) is forward through the current path indicated by arrow B and through the optic nerve hole to the forehead. It is thought that it flows. In this case, the fact that the optic nerve is actually stimulated to feel flickering can be cited as this evidence. In order to give an acceleration feeling in the front-rear direction, the skin surface near the orbit, for example, at the center of the right and left orbit, based on the technical idea of flowing current from the skull hole of the present invention as a position to apply an effective interval stimulation current By providing the electrode arrangement portion of the electrode, the electrical stimulation current can be efficiently applied with less leakage current.
For example, as shown in FIG. 17, an electrode placement site is set on the forehead near the orbit, and the skin surface electrode Q1 is attached to this electrode placement site. As the counter electrode, the skin surface electrodes Q2 and Q3 are attached to any of the electrodes A to E already described, that is, to an electrode arrangement site (an example of the tragus in FIG. 17) set in the vicinity of the ear canal.

On the other hand, when the electrode placement site is set in the oral cavity with respect to the electrode placement site of the electrode described above and the intraoral electrode Q4 is mounted on the upper palate as shown in FIG. A current path is formed in the direction of arrow C (FIG. 16). An electrical sensation current generated by the skin surface electrodes Q2 and 3 and the intraoral electrode Q4 and including a vestibular organ in the skull in the path causes an acceleration sensation in the vertical direction for the user wearing it. I will let you.
As a result, the fact that a sense of acceleration in the vertical direction is obtained is a new discovery, and at the same time, vestibular stimulation in the front and rear (x direction), left and right (y direction), and vertical (z direction) directions is performed on the skin surface electrode. Since it can be performed by applying a sensory stimulation current to Q1, Q2, Q3 and intraoral electrode Q4, knowledge that enables vestibular electrical stimulation in all directions in three dimensions was obtained.

Current path of sensory stimulation current before and after Skin surface electrode Q2 (or Q3) mounted in the vicinity of the external auditory canal → outer ear canal → inner ear canal → vestibular organ → optic nerve → eye socket → skin surface electrode Q1 (in this case, viewed from the front of the face The left side (corresponding to the skin surface electrode Q2) and the right side (corresponding to the skin surface electrode Q3) have different current paths)
-Current pathway of upper and lower sensory stimulation currents Skin surface electrode Q2 (or Q3) mounted in the vicinity of the external auditory canal-> external auditory canal-> inner ear canal-> vestibular organ-> ear canal-> carotid artery-> upper palate-> intra-palate electrode Q4

G. Mouthpiece type electrode As shown in FIG. 18, the mouthpiece type electrode is obtained by applying a mouthpiece for boxing as a base 90, and is made of insulating resin or rubber. A groove 92 is provided on the upper surface (and lower surface) of the base 90 for fixing by teeth, and an electrode 91 is formed on the surface of the base 90 by a conductor such as metal or conductive resin inside the groove 92. ing. An interval stimulation current is applied to the electrode 91 from the electrical stimulation device via a cable. The electrode 91 can be formed with an area that is in close contact with the upper palate, and the current density of the contact surface between the electrode 91 and the upper palate can be reduced, so that a sensory stimulation current is applied without giving a painful stimulus. Can do.

H. Spoon Type Electrode As shown in FIG. 19, this spoon type electrode uses a spoon-shaped base 95, and is composed of insulating resin or rubber. An electrode 96 is formed on the upper surface of the base 95 by a conductor such as metal or conductive resin. Similar to the mouthpiece type electrode, an interval stimulation current is applied to the electrode 96 from the electrical stimulation device via a cable. Similarly to the mouthpiece type electrode, the electrode 96 can be formed with an area that is in close contact with the upper portion of the palate, and the current density on the contact surface between the electrode 96 and the upper portion of the palate can be reduced, so that no pain sensation is given. A sensory stimulation current can be applied to the.
In addition to the G and H electrodes, other mounting methods such as mounting on the tongue or sublingually, storing saliva in the mouth, and immersing the electrode are also conceivable. However, the G and H electrodes have the advantage of less influence of taste stimuli during use over these other mounting methods.

  7 and 9 are recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system and executed. An electrical stimulation signal generation process may be performed. Here, the “computer system” includes an OS and hardware such as peripheral devices. The “computer system” includes a WWW system having a homepage providing environment (or display environment). The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Further, the “computer-readable recording medium” refers to a volatile memory (RAM) in a computer system that becomes a server or a client when a program is transmitted via a network such as the Internet or a communication line such as a telephone line. In addition, those holding programs for a certain period of time are also included.

  The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line. The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

  INDUSTRIAL APPLICABILITY The present invention is used in an electrical stimulation method and apparatus for stimulating an organ that responds to stimulation including a vestibular sensation and muscle by passing a weak current.

It is a conceptual diagram which shows the position of the electrode arrangement | positioning site | part for demonstrating the design concept of this invention. It is the table | surface which measured the resistance value between each electrode arrangement | positioning site | part shown in FIG. It is a graph which shows the resistance value of the measurement in each group which divided the table of FIG. 2 into groups by the space | interval of an electrode arrangement | positioning site | part. It is a graph which shows a response | compatibility with the distance of an electrode arrangement | positioning site | part calculated by the theoretical formula by a geometric calculation model, and resistance value. It is the conceptual diagram seen from the parietal part which shows the electric current path | route which penetrates the inside of a cranium (the electric current path is shown by resistance). It is a conceptual diagram showing a geometric calculation model in which the head is spherical, the skull is an insulator, and the skin on the outer surface of the skull is a spherical shell resistor. It is a block diagram which shows the structural example of the electrical stimulation apparatus 100 by embodiment of this invention. 6 is a graph showing a current waveform by the electrical stimulation device 100. It is a block diagram which shows the structural example of the electrical stimulation apparatus 110 by other embodiment of this invention. It is the conceptual diagram seen from the left side of the human head for showing the electrode arrangement | positioning site | part of a tragus pin type | mold electrode. It is a conceptual diagram which shows an example of the structure of the tragus sandwiching type electrode by embodiment of this invention. It is the conceptual diagram seen from the right back side of a human head for showing the electrode arrangement part of an auricle base ring type electrode. It is a conceptual diagram which shows an example of the structure of the pinna base ring type electrode by embodiment of this invention. It is a conceptual diagram which shows an example of the structure of the spectacles ear hanging type | mold electrode by embodiment of this invention. It is a conceptual diagram which shows an example of the structure of the headphone-type electrode for ears by embodiment of this invention. It is a conceptual diagram in a cranium explaining the path | route of an interval stimulation current. It is a front view of a person's face explaining the electrode arrangement | positioning site | part of this invention. It is a conceptual diagram which shows an example of the structure of the mouthpiece-type electrode by embodiment of this invention. It is a conceptual diagram which shows an example of the structure of the spoon type electrode by embodiment of this invention. It is a conceptual diagram which shows an example of the structure of the earphone type electrode of an in-ear shape by embodiment of this invention. It is a figure which shows the example of mounting | wearing with the conventional electrical stimulation apparatus 200. FIG. It is a figure which shows the relationship between the polarity of the electric current by the electric stimulator 200, and a walking direction. 5 is a graph showing a walking trajectory in walking guidance using the electrical stimulation device 200.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Current command value output part 20 ... Current change amount control part 21 ... Constant value output part 22, 25 ... Gain adjuster 23 ... Switch 24 ... Integrator 26 ... Comparator 27 ... User stimulus adjustment knob 40 ... Constant current generation / Control unit 41 ... Power source 42 ... Current detector 43 ... Current regulator 44 ... User skin electrode 44a, 44b ... Skin surface electrode 45 ... Comparator 51, 150 ... Base 52 ... Conductive rubber layer 53, 63, 72, 82, DESCRIPTION OF SYMBOLS 160 ... Conductive gel layer 55A, 55B, 61A, 61B, 80 ... Fixed part 56 ... Spring mechanism part 57 ... Lever 60 ... Operation / adjustment changeover switch 61 ... Base material 62, 71, 81 ... Conductive rubber 90 ... Main body 100 110 ... electric stimulation device a, b ... contact c ... common contact

Claims (3)

A current command value generator for generating a sensory stimulation current for stimulating the vestibular sensation;
An electrical stimulation unit that outputs the sensory stimulation current;
A sensory stimulation electrode to be mounted in the vicinity of the ear canal , wherein the current path of the sensory stimulation current is a region mainly including a vestibular organ ,
An electrical stimulation apparatus comprising: an intracranial sensory stimulation electrode provided as a counter electrode of the sensory stimulation electrode, mounted in a palate, wherein the current path of the sensory stimulation current is a region mainly including a vestibular organ . A current command value generator for generating a sensory stimulation current for stimulating the vestibular sensation;
An electrical stimulation unit that outputs the sensory stimulation current;
A sensory stimulation electrode to be mounted in the vicinity of the ear canal, wherein the current path of the sensory stimulation current is a region mainly including a vestibular organ,
A forehead sensory stimulation electrode that is mounted in the vicinity of the orbit and provided as a counter electrode of the sensory stimulation electrode, wherein the current path of the sensory stimulation current is a region mainly including a vestibular organ.
An electrical stimulation device comprising: A current command value generator for generating a sensory stimulation current for stimulating the vestibular sensation;
An electrical stimulation unit that outputs the sensory stimulation current;
A sensory stimulation electrode to be mounted in the vicinity of the ear canal, wherein the current path of the sensory stimulation current is a region mainly including a vestibular organ,
In the palate sensory stimulation electrode to be mounted in the palate, the current path of the sensory stimulation current is a region mainly including a vestibular organ,
An electrical stimulation device comprising: a forehead sensory stimulation electrode mounted in the vicinity of the orbit, wherein the current path of the sensory stimulation current is a region mainly including a vestibular organ.

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