JPH0414587B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention is directed to a state of mental relaxation (relaxation state) in which alpha waves mainly appear due to abdominal breathing.
The present invention relates to a biofeedback device for guiding subjects to the subject.

(Prior art) Conventionally, in brain wave research, it has been known that beta waves of 13 to 22 Hz mainly appear in brain waves when the mind is under stress. For those who have been trained in
It is known that in a so-called meditative state where the mental state is extremely stable, alpha waves of 8 to 13 Hz primarily appear in brain waves.

Therefore, in the field of mental health care, a so-called biofeedback device has been devised to keep the mental state in a relaxed state and enhance relaxation by consciously sustaining the state of alpha waves. There is.

Such conventional biofeedback devices include electroencephalogram, muscle current, and galvanic skin response (GSR).
These physical information are electrically detected, and the treatment staff monitors this physical information and provides training and guidance to the patient to achieve a state of mental relaxation.

(Problems to be solved by the invention) However, since such conventional biofeedback devices were mainly used in medical institutions, brainwaves, human body information, etc.
The state of relaxation is determined by electrically detecting weak signals such as muscle currents and electrodermal reactions. For this reason, for example, in the electroencephalogram detection method and muscle current detection method, electrodes are placed on the head and arms. It could not be expected to be of general use because it gave subjects a sense of tension and discomfort when worn, and there were restrictions on the usage environment and conditions, such as the need to keep the electrode surface wet at all times.

In addition, with regard to the electrodermal reaction detection method, there are individual differences between people, such as those who are more likely to experience changes and those who are less likely to do so, and they are also susceptible to the effects of the surrounding environment such as temperature and humidity. General use was difficult.

(Means for Solving the Problems) The present invention has been made in view of the problems of the prior art, and it is used not only in medical institutions but also in ordinary homes to train subjects to induce a relaxed state in which their minds are stable. It is an object of the present invention to provide a biofeedback device that can be easily and easily operated by oneself.

In order to achieve this objective, the inventors of the present application have conducted extensive research focusing on the relationship between breathing and brain waves, and based on statistical results, they have found the following regarding the enhancement of alpha waves that achieve a state of mental relaxation. I have come to a conclusion.

First, abdominal breathing is more advantageous than chest breathing in enhancing alpha waves.

Second, even with abdominal breathing, the incidence of alpha waves is higher when the number of breaths is smaller and the movement of the abdominal wall is larger.

Thirdly, the smaller the breathing ratio defined by (inhalation time)/(expiration time), the higher the incidence of alpha waves.

Based on such research results, in order to solve the above-mentioned problems, the present invention detects a signal corresponding to the movement of the abdominal wall due to abdominal breathing with a sensor attached to the abdomen of the subject, and uses this detection signal to determine the inspiratory flow. In addition to measuring the exhalation time and expiration time, the breathing ratio is calculated from both, and this breathing ratio is compared with a predetermined reference value to determine whether or not the patient is in a relaxed state. This is to notify the subject.

(Function) According to the biofeedback device of the present invention, since the sensor detects the movement of the abdominal wall due to abdominal breathing, that is, the displacement of the abdominal wall in the distended state and the relaxed state, it is possible to detect the conventional brain waves. , muscle current,
Unlike GSR, there is no need to attach special electrodes,
Further, since the displacement of the abdominal wall is sufficiently large, the S/N ratio of the sensor detection signal is also high, and the sensor can be easily used without being restricted by the usage environment. In addition, the subject performs abdominal breathing so that the exhalation time is longer than the inhalation time, and when the subject reaches a relaxed state in which alpha waves continue to be generated, the subject learns from acoustic output etc. that the subject is in a relaxed state by comparing and calculating the breathing ratio. This allows the test subject to reach a relaxed state of mind with enhanced alpha waves on his or her own without special training and guidance, making it possible to use it at home.

(Embodiment) FIG. 1 is a block diagram showing an embodiment of the present invention.

First, to explain the configuration, numeral 1 is a sensor section that is attached to the abdomen of the subject and outputs a signal according to the movement of the abdominal wall due to abdominal breathing. Measuring instruments etc. are used. The detection signal of the sensor section 1 is given to an expiration/inspiration time measuring section 2, and the expiration/inspiration time measuring section 2 measures an inhalation time Ti and an expiration time To on a breathing code.

Inspiratory time measured by expiratory/inspiratory time measurement unit 2
For example, the sensor detection signal of the distended state and relaxed state due to abdominal breathing detected by the sensor unit 1 is as shown in FIG. Since the differential signal shown in b is obtained, the time during which the differential signal is (+) is measured as the inhalation time Ti, and the time To during which the differential signal is (-) is measured as the exhalation time.

More specifically, the gate signal shown in FIG. 2c is generated from the differential signal shown in FIG. 2b,
While the gate signal is at H level, a clock pulse is supplied to the intake time counter to calculate the intake time.
While the gate signal is at L level, a clock pulse is supplied to the expiration time counter to count the expiration time To.

Referring again to FIG. 1, each of the expiration time Ti and the expiration time To measured by the expiration/inspiration time measurement section 2 is provided to the breathing ratio calculation section 3.

The breathing ratio calculation unit 3 calculates a plurality of inspiratory times Ti1 to Tin and expiratory times obtained in a unit time, for example, one minute.
The average values Tia and Toa of To1 to n are calculated, and based on these average values, the respiratory ratio K is calculated as K=Tia/Toa (1).

The breathing ratio K calculated by the breathing ratio calculation section 3 is given to the comparison section 4, and the comparison section 4 sets the reference value setting section 5.
It is compared with the reference value Ko set by.

Here, the reference value Ko by the reference value setting unit 5 is a reference value for determining whether the breathing ratio K calculated by the above-mentioned formula (1) has reached a state of mental relaxation in which alpha waves are generated. When the respiration ratio K is determined from the above equation (1), the reference value Ko is set to an appropriate value of 1 or less. In other words, the state of mental relaxation in which the generation of alpha waves is enhanced is an abdominal breathing state in which the expiration time To is sufficiently long compared to the expiration time Ti, as shown in Figure 2a, and the state of mental relaxation in which the generation of alpha waves is enhanced is an abdominal breathing state in which the expiration time To is sufficiently long compared to the expiration time Ti. When the calculated breathing ratio K falls below the reference value Ko to be taken, the comparator 4 outputs a relaxation state discrimination signal, indicating that the relaxation state has been reached.

The relaxation state determination signal from the comparison unit 4 is given to a sound generation unit 6 provided as a notification means, and when the sound generation unit 6 receives the relaxation state determination signal from the comparison unit 4, it outputs a speaker 7 or a headphone 8.
A sound is played using earphones (or earphones may be used) to notify the subject of the arrival of a relaxed state.

The above circuit configuration is the basic configuration of the biofeedback device according to the present invention, but in the embodiment shown in FIG. A photoelectric display section 10 activated by the sensor section 10 is provided as a notification means, and for example, the number of lighted lamps provided on the photoelectric display section 10 is increased in accordance with the signal level of the detection signal from the sensor section 1. This makes it possible to visually display the state of abdominal breathing performed by the subject.

Furthermore, in the embodiment shown in FIG.
A breathing depth measuring section 11 is provided which measures the depth of breathing based on a detection signal from the breathing depth measuring section 11, and the breathing depth measurement signal from this breathing depth measuring section 11 is also given to the display driving section 9 and photoelectrically displayed. The depth of breathing can be displayed on the equation display section 10 by controlling the lighting of a plurality of lamps.

The breathing depth measured by this breathing depth measuring section 11 can be determined by, for example, measuring the level difference ΔV between the highest and lowest values of the detection signal shown in FIG. It is measured as the integral value of the detection signal over the expiration time To.

Note that the visual display of the breathing state and/or the depth of breathing by the photoelectric display unit 10 is provided supplementary to the acoustic notification by the sound generating unit 6. That is, since a relaxed state in which the generation of alpha waves is enhanced is more easily achieved with the eyes closed or half-eyed than with the eyes open, the display on the photoelectric display unit 10 is only for reference for the subject.

Next, the operation of the embodiment shown in FIG. 1 will be explained with reference to the flowchart shown in FIG.

First, the power to the device is turned on with the sensor unit 1 fixed to the abdomen with a band or the like, and the subject takes a deep breath while sitting in a stable position on a chair or the like and performs deep abdominal breathing. Based on the detection signal from the sensor unit 1 due to abdominal breathing by the subject, the inspiratory time Ti and expiratory time To are measured in block 20 every time abdominal breathing is performed.
Determination block 22 checks whether one minute has passed since the start of the first measurement.
0 and the processing of the discrimination block 22, the inspiratory time Ti and expiratory time To in abdominal breathing for one minute
is measured. When one minute has elapsed from the start of the measurement, the process advances from judgment block 22 to block 24, where the inspiratory time Ti and expiratory time To obtained by abdominal breathing for one minute are calculated.
The average times Tia and Toa are calculated, and the respiration ratio K is calculated in block 26 based on these average values. Next, in judgment block 28, the preset reference value is
Ko and the calculated breathing ratio K are compared, and when the calculated breathing ratio K is larger than the reference value Ko, the process returns to block 20, and on the other hand, when the calculated breathing ratio K is less than the reference value Ko. When this occurs, the process proceeds to block 30, where the test subject is informed by acoustic output that the patient has entered a relaxed state in which the generation of alpha waves is enhanced, and the process returns to block 20, which is a time measurement process.

Note that the reference value Ko for determining the relaxed state by the reference value setting unit 5 shown in FIG. 1 takes a value of 1 or less, but the value of the reference value Ko can be freely changed depending on the subject. . In other words, if the subject's level of training is low, a higher standard value Ko is set,
As the training progresses, the reference value Ko is changed to a smaller value, and by changing the setting of the reference value Ko in this manner, it is possible to display the relaxed state in accordance with the degree of training.

FIG. 4 is a block diagram showing another embodiment of the present invention, and this embodiment is characterized in that the number of breaths during abdominal breathing is measured and displayed.

That is, the detection signal from the sensor section 1 is input to the respiration rate measuring section 12, and the respiration rate measuring section 12 measures the number of respirations N per unit time, for example, per minute. The respiration rate N measured by the respiration rate measurement unit 12 is given to the comparison unit 13, and the reference rate setting unit 14
When the measured number of respirations N becomes less than or equal to the reference number No., the display driver 9 causes the photoelectric display 10 to display that the number of respirations has also reached a relaxed state. That's what I do.

It should be noted that the number N measured by the respiratory rate measuring section 12 may be directly supplied to the display driving section 9 and the respiratory rate itself displayed on the photoelectric display section 10 without being compared with the reference number No. in the comparing section 13. good.

Note that the other circuit configurations are the same as the embodiment shown in FIG.

Furthermore, in the embodiments shown in FIGS. 1 and 4, the relaxation state determination output based on the breathing ratio K determined by the comparison unit 4 is notified to the subject only as an acoustic output by the sound generation unit 6. As shown by the dotted line, the output of the comparison section 4 is applied to the display drive section 9, and the photoelectric display section 1
0 may be displayed to indicate that the relaxed state has been reached.

Furthermore, the biofeedback device of the present invention includes:
The circuit may be configured by hardware as shown in FIGS. 1 and 4, or may be realized by program control by a microcomputer as shown in the flowchart of FIG.

Furthermore, in the above embodiment, the breathing ratio is calculated as (inhalation time)/(expiration time), but it may also be calculated as (expiration time)/(inspiration time).
In this case, the reference value for determining the relaxed state is set to an arbitrary value of 1 or more, and when this reference value is exceeded, an output for determining the relaxed state is generated.

(Effects of the Invention) As explained above, according to the present invention, the subject performs abdominal breathing so as to obtain an output for determining the relaxed state, thereby achieving a mentally relaxed state in which the incidence of alpha waves is enhanced. This state of mental relaxation, in which the incidence of alpha waves increases, can be easily achieved by the subject himself, and with repeated use of the device, the state of mental relaxation can be measured. By increasing the training level of abdominal breathing to a relaxed state and achieving a state of mental relaxation, imagination such as inspiration increases and free thinking is possible, and it is also very effective in recalling memories.
Furthermore, it can be expected to have great mental and functional effects through home use, such as making it easier to find solutions to given problems and enhancing memory ability.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a signal waveform diagram showing the detection signal from the sensor section of FIG. FIG. 4 is a flowchart showing the operation process of the invention, and a block diagram showing another embodiment of the invention. 1: Sensor part, 2: Exhalation/inspiration time measuring part,
3: Breathing comparison calculation section, 4, 13: Comparison section, 5: Reference value setting section, 6: Sound generation section, 7: Speaker,
8: Headphone, 9: Display drive section, 10: Photoelectric display section, 11: Breathing depth measuring section, 12: Breathing frequency measuring section, 14: Reference frequency setting section.

Claims (1)

[Scope of Claims] 1. A sensor that is attached to the abdomen of a subject and outputs a signal according to the movement of the abdominal wall due to abdominal breathing, and a breathing time that measures the inhalation time and expiration time based on the detection signal from the sensor. a measuring means, a calculating means for calculating the time ratio between the inspiratory time and the expiratory time measured by the respiration time measuring means as a respiration ratio, and comparing the respiration ratio obtained from the calculating means with a predetermined reference value. A biofeedback device characterized by comprising: a determining means for determining a relaxed state in which alpha waves mainly appear; and a reporting means for receiving the determination output of the determining means and notifying the subject that the subject is in a relaxed state. . 2. The biofeedback device according to claim 1, wherein the notifying means includes a sound generating section that notifies the relaxed state by sound output. 3. The biofeedback device according to claim 1, wherein the notification means includes a display section that visually displays the relaxed state. 4. The bio-office according to claim 2 or 3, wherein the notification means includes means for displaying the depth of respiration and/or the number of respirations in addition to the relaxation state notification means. Eid back device. 5. The biofeedback device according to claim 4, wherein the respiration frequency display means includes means for displaying that the respiration frequency per unit time has become equal to or less than a predetermined reference number of times.