JP5900153B2 - Information processing apparatus, sleep state evaluation method, sleep state evaluation program, and evaluation system - Google Patents

Description

  The present invention relates to an information processing device, a sleep state evaluation method, a sleep state evaluation program, and an evaluation system.

  Healthy people are able to turn over moderately during sleep. Rolling over has the role of relieving body pain and blood flow squeezed by weight. For this reason, it is considered indispensable to turn over moderately to obtain good sleep, but elderly people with impaired exercise ability, Parkinson's disease patients, etc. cannot turn over well. Moreover, even if it is a healthy person, when it is hard to sleep, the number of times of turning over increases.

  In short, turning over reflects the person's overall health as well as during sleep. Therefore, it is very important to quantitatively evaluate the rollover from the viewpoint of daily health management, and a method of measuring the rollover with a mat-type sensor non-invasively and without restraint (for example, Patent Document 1). And a method of measuring a turn by attaching an acceleration sensor to the body (for example, see Patent Document 2).

JP 2011-21858 A JP 2010-148829 A International Publication No. 2011/040259 Pamphlet

  About turning over, it is defined in the “Regarding correction of notification related to revision of medical fee in FY 2008” by the Ministry of Health, Labor and Welfare as “the operation to move from the supine position to either the left or right side”. Therefore, in the field of nursing, it is not determined that a person will be turned upside-down unless he / she is in a complete lateral position, but in general, a case where he / she does not turn sideways is also considered to be turned over.

  In this way, the definition of turning over remains ambiguous. Therefore, when quantifying the frequency and angle of turning over, a method is adopted in which a certain threshold value is provided, and when the body rotates around the body axis exceeding the threshold value, it is counted as turning over. However, in this method, if the threshold value is set incorrectly, the sleep state of the subject is erroneously evaluated.

  Therefore, an object of the present invention is to provide an information processing apparatus, a sleep state evaluation method, and a sleep state evaluation program that can evaluate a subject's sleep state in such a way that the sleep state of the subject is not erroneously evaluated due to a mistake in setting a threshold. And providing an evaluation system.

In order to solve the above problems, one of the aspects of the present invention is an information processing apparatus,
Based on a plurality of turning angles A that are rotation angles around the body axis in each turning behavior performed by the subject during bedtime, for each of a plurality of angle values A, the turning behavior of the subject with a turning angle of A degree or more is set. A frequency value calculation unit for calculating a frequency value Z (A) representing an execution frequency;
A plurality of frequency values Z (A calculated by the frequency value calculation unit for the plurality of angle values A
) On the basis of the calculation and output unit for calculating and outputting the turnover frequency factor α for the subject,
Is provided.

  That is, the information processing apparatus according to the present invention has a function of calculating and outputting a turnover frequency factor α corresponding to the number of execution times of the subject's turnover behavior (the turnover operation and the operation to turn over). Such a turnover frequency factor α is a value that has a correlation with the sleep state of the subject and a value that can be uniquely determined without setting a threshold value for determining whether or not the subject has turned over. . Therefore, if this information processing apparatus is used, the sleep state of the subject can be evaluated in such a way that the sleep state of the subject is not erroneously evaluated due to a mistake in setting the threshold value.

In realizing the information processing apparatus of the present invention, when the frequency value Z (A) is, in said plurality of turn angle, the number of turn angle whose value is in the x and denoted as P (x) It can be made to become a value represented by the following formula.

  Further, as the frequency value Z (A), the sum of the maximum values of the turning angle in each time zone in which the turning behavior with a turning angle of A degrees or more is continuously performed can be calculated.

Further, as the calculation / output unit of the information processing apparatus of the present invention, α and β are set so that each Z (A) calculated by the frequency value calculation unit is approximated by the following regression equation. It is possible to employ one that calculates and outputs the calculated α as the rolling frequency factor α.

  Further, as the calculation / output unit, a unit that outputs the calculated α as the turnover frequency factor and outputs the calculated β as the turnover energy β can be adopted.

  Further, the information processing apparatus according to the present invention, based on the turnover frequency factor α calculated by the calculation / output unit, determines whether the sleep state of the subject is a plurality of predetermined sleep states, It is also possible to realize a sleep state evaluation unit that outputs a discrimination result as a device further provided.

The information processing apparatus of the present invention
A frequency value calculation process for calculating the frequency value Z (A) for each angle value A from the turn angle related to the turnover behavior made in the evaluation time zone corresponding to the first time width in the plurality of turn angles, A second frequency value calculation unit that executes for each of a plurality of evaluation target time zones with different start times;
For each of the plurality of evaluation target time zones, the turnover frequency factor α is calculated from the plurality of frequency values Z (A) calculated by the frequency value calculation processing related to the evaluation target time zone, and for each evaluation target time zone A second calculation / output unit for outputting the calculated turnover frequency factor α in a form in which the correspondence relationship with the evaluation target time zone is understood;
Can also be realized as a further equipped device.

The information processing apparatus of the present invention is
Based on rotation angle information including a rotation angle around the body axis of the subject who is sleeping for each of a plurality of times, a turn angle information generating unit that generates a turn angle information including a plurality of turn angles is further provided,
The frequency value calculation unit is realized as a device that calculates the frequency value Z (A) for each angle value A based on the plurality of turn angles in the turn angle information generated by the turn angle information generation unit. You can keep it.

Further, when realizing the information processing apparatus of the present invention as such a device,
The rotation angle information includes a fall angle that is an inclination angle of the body axis of the subject at each time for each of the plurality of times,
The turning angle information generating unit can generate the turning angle information only from the rotation angle in which the fall angle is an angle within a specified range in the rotation angle information.

Further, the information processing apparatus according to the present invention generates the turning angle information including a plurality of turning angles from the acceleration information in three directions for the sleeping subject recorded in time series by the motion sensor. Part further,
The frequency value calculation unit is configured as a device that calculates the frequency value Z (A) for each angle value A based on the plurality of turn angles in the turn angle information generated by the turn angle information generation unit. You can also keep it.

  Moreover, the other aspect of this invention is a computer-readable medium which recorded the sleep state evaluation method, sleep state evaluation program, evaluation system, and sleep state evaluation program which have the characteristic similar to information processing apparatus.

  According to the present invention, an information processing apparatus, a sleep state evaluation method, a sleep state evaluation program, and an evaluation that can evaluate a subject's sleep state in a manner that does not erroneously evaluate the sleep state of the subject due to a mistake in setting a threshold value. Can provide a system.

FIG. 1A is a schematic configuration diagram of a sleep state evaluation system according to an embodiment of the present invention. FIG. 1B is a functional block diagram of the information processing apparatus included in the sleep state evaluation system according to the embodiment. FIG. 2 is a flowchart of analysis processing executed by the information processing apparatus in the sleep state evaluation system according to the embodiment. FIG. 3A is an explanatory diagram of a rotation angle. FIG. 3B is an explanatory diagram of the falling angle. FIG. 4 is an explanatory diagram of a procedure for calculating the turning angle. FIG. 5 is an explanatory diagram of data prepared in the information processing apparatus by analysis processing. FIG. 6 is an explanatory diagram of data (turning angle group) prepared in the information processing apparatus by analysis processing. FIG. 7 is a graph showing the relationship between the A value and the logZ (A) value. FIG. 8 is an explanatory diagram of the relationship between the turnover frequency factor and the turnover energy and the sleep state of the subject. FIG. 9 is an explanatory diagram of the relationship between the turnover frequency factor and the turnover energy and the sleep state of the subject. FIG. 10 is a flowchart of second analysis processing executed by the information processing apparatus according to the embodiment. FIG. 11 is an explanatory diagram of an example of a processing result obtained by the second analysis processing. FIG. 12 is an explanatory diagram of information obtained from the processing result of the second analysis processing. FIG. 13 is an explanatory diagram of a calculation method of Z (A) that can be employed.

  Embodiments of the present invention will be specifically described below with reference to the drawings.

  FIG. 1A shows a configuration of a sleep state evaluation system according to an embodiment of the present invention.

  The sleep state evaluation system according to the present embodiment is a system used for evaluating the sleep state of a human (hereinafter referred to as a subject). As illustrated, the sleep state evaluation system includes a subject behavior measurement device 10 and an information processing device 20.

  The subject behavior measuring device 10 according to the present embodiment is a small device (so-called motion sensor) that is fixed to the subject's body in order to measure the motion of the subject's body during sleep. Although FIG. 1 shows a state in which the subject behavior measuring device 10 and the information processing device 20 are connected by the cable 18, this sleep state evaluation system is usually “independent (information processing device The subject behavior measuring apparatus 10 is made to function by connecting the subject behavior measuring apparatus 10 to the information processing apparatus 20 after the subject behavior measuring apparatus 10 collects information related to the body movement of the subject. The information collected by the information processing device 20 is analyzed ”.

  As shown in FIG. 1, the subject behavior measuring apparatus 10 includes an inertial sensor 11, a storage unit 12, an interface circuit (IF in the figure) 13, and a microprocessor 14. In addition, the subject behavior measuring apparatus 10 starts recording a battery (secondary battery; not shown) for supplying power to each unit in the apparatus, and recording acceleration (details will be described later) into the storage unit 12 by the microprocessor 14. Also provided is a slide switch (not shown) for ending.

  The inertial sensor 11 is a triaxial acceleration sensor that can measure accelerations in the X, Y, and Z axis directions. In the subject behavior measuring apparatus 10, the X, Y, and Z axis directions of the inertial sensor 11 are the subject's left-right direction (left is a plus direction), up-down direction (up is a plus direction), and front-back direction (front is a plus direction). ) Is fixed to the subject by a dedicated belt or the like. In addition, the fixed position of the test subject behavior measuring apparatus 10 is usually the center of the trunk (the center of the abdomen or the center of the back). Hereinafter, the X, Y, and Z axis directions of the inertial sensor 11 in the subject behavior measuring apparatus 10 fixed to the subject are denoted as the X, Y, and Z directions of the subject, respectively.

  The storage unit 12 is a storage device for storing a measurement result of acceleration by the inertial sensor 11. The storage unit 12 of the subject behavior measuring apparatus 10 according to the present embodiment is a memory card (flash ROM (Read Only Memory)) that can be removed from the subject behavior measuring apparatus 10.

The interface circuit 13 is a unit (in this embodiment, a so-called USB (Universal Serial Bus) interface circuit) for performing communication (information exchange) with the information processing apparatus 20. The interface circuit 13 is also used for charging the battery of the subject behavior measuring apparatus 10. Note that the subject behavior measurement device 10 and the information processing device 20 each have a wireless communication interface, and exchange of information (including subject behavior information described later) between them is performed through a wireless link. You can also. In addition, the subject behavior measuring device 10 and the information processing device 20 each include a drive device for a portable recording medium (for example, an SD card), so that information can be exchanged from one of the portable recording media. It may be implemented by mounting on the other side and reading information.

  The microprocessor 14 is a processor capable of executing processing (hereinafter referred to as measurement recording processing) for periodically recording the measurement results of acceleration in the X, Y, and Z directions of the subject by the inertial sensor 11 in the storage unit 12. . The microprocessor 14 is configured (programmed) so as to set (specify) an acceleration recording period during measurement recording processing by transmitting a command in a predetermined format from the information processing apparatus 20.

  Further, when the slide switch provided in the subject behavior measuring apparatus 10 is turned ON, the microprocessor 14 records the current time and the set recording cycle in the storage unit 12 and is then set. The measurement recording process is started at a certain recording cycle, and the measurement recording process is terminated when the slide switch is turned off. This processing (processing for recording the current time and recording cycle in the storage unit 12 + measurement recording processing) performed by the microprocessor 14 is performed by storing various data in the storage unit 12 as files having file names generated from the current time. It is a process to memorize.

The information processing apparatus 20 includes a computer storage unit 24 (HDD (Hard Disk Drive)) including an input device 21 (keyboard, mouse, etc.), a display 22, a computer main body 23, and the like.
, SSD (Solid State Drive), etc.) is a device in which the sleep state evaluation program 35 developed for this system is installed. Note that the storage unit 24 (HDD, SSD, etc.) of the information processing apparatus 20 corresponds to a computer-readable medium. Further, the information processing apparatus 20 (computer functioning as the information processing apparatus 20) may be a PC (Personal Computer), WS (Work Station) or the like, a mobile phone, a smartphone, or the like. Installation of the sleep state evaluation program 35 on the computer (information processing apparatus 20) is performed by reading from a portable recording medium such as a CD-ROM in which the sleep state evaluation program 35 is recorded or downloading from a server.

  Hereinafter, functions of the information processing apparatus 20 will be described. In the following description, the subject behavior information is information including measurement results of acceleration in three directions at each time of the subject stored as a file in the storage unit 12 by operating the subject behavior measuring apparatus 10. It is.

  FIG. 1B shows a functional block diagram of the information processing apparatus 20 according to the present embodiment. As shown in the figure, the computer main body 23 (mainly the CPU 31) of the information processing apparatus 20 according to the present embodiment includes a turning angle information generation unit 40, a frequency value calculation unit 41, a calculation / output unit 42, and a sleep state evaluation unit. 43, functions as a second frequency value calculation unit 44 and a second calculation / output unit 45.

  The turning angle information generation unit 40 uses a plurality of turning angles from the subject behavior information on the storage unit 12, that is, the acceleration information in three directions about the sleeping subject recorded in time series by the subject behavior measuring device 10. Is a unit (functional block) for generating the turn angle information including. The turn-over angle is a rotation angle around the subject's body axis in each turn-over behavior (turn-over operation, operation to try to turn over) performed by the subject.

This turn angle information generation unit 40 may generate turn angle information including turn angles at all times (all turn angles that can be calculated from subject behavior information). However, the turning angle information generating unit 40 included in the information processing apparatus 20 according to the present embodiment calculates the average value of the turning angle for each predetermined time as the turning angle for each predetermined time. Further, the turning angle information generating unit 40 obtains the falling angle (inclination angle) of the body axis and the rotation angle around the body axis of the sleeping subject at each time based on the subject behavior information, and the falling angle is within a specified range. The turning angle information is generated only from the rotation angle that is the inner angle.

  When the information processing device 20 is configured as a device that processes the turn angle information generated by another device (device equivalent to the subject behavior measurement device 10), the turn angle information generation unit 40 is removed from the information processing device 20. You can keep it.

  The frequency value calculation unit 41 has a turn behavior of a subject whose turn angle is greater than or equal to A degrees for each of a plurality of angle values A based on the plurality of turn angles in the turn angle information generated by the turn angle information generation unit 40. This is a unit for calculating a frequency value Z (A) representing the execution frequency. The frequency value calculation unit 41 according to the present embodiment, as the frequency value Z (A), the number P (x) of the turn angles whose value is x among the plurality of turn angles included in the turn angle information. The value represented by the following formula is calculated.

That is, the frequency value calculation unit 41 according to the present embodiment calculates the sum of the turning angles included in the turning angle information whose value (angle) is A degrees or more as the frequency value Z (A). It has become.

  However, the frequency value Z (A) may be a value representing the execution frequency of the turning behavior of the subject whose turning angle is A degrees or more. Therefore, the frequency value calculation unit 41 can be configured to calculate the frequency value Z (A) by an expression different from the expression (1) (details will be described later).

  The calculation / output unit 42 is a unit that calculates and outputs a turnover frequency factor α (details will be described later) of the subject based on each frequency value Z (A) calculated by the frequency value calculation unit 41. The calculation / output unit 42 outputs the calculated rollover frequency factor α to the display 22 as schematically shown by an arrow in FIG. 1B. That is, the calculation / output unit 42 according to the present embodiment is a unit that displays information representing the calculated turnover frequency factor α on the screen of the display 22. However, the calculation / output unit 42 only needs to calculate the rollover frequency factor α and output it in some form. Accordingly, the calculation / output unit 42 is configured to cause the printer to print the calculated turnover frequency factor α, or to store the calculated turnover frequency factor α in a storage device (the storage unit 24 or a USB attached to the USB port of the information processing device 20). The unit can be stored in a memory or the like.

The sleep state evaluation unit 43 determines whether the sleep state of the subject is a predetermined number (for example, three) of sleep states based on the turnover frequency factor α calculated by the calculation / output unit 42. And a unit for outputting a discrimination result. As schematically shown in FIG. 1B, the sleep state evaluation unit 43 according to the present embodiment is also a unit that outputs the discrimination result to the display 22 (displays the discrimination result on the screen of the display 22). . However, the sleep state evaluation unit 43 only needs to determine the sleep state of the subject based on the turnover frequency factor α and output the determination result in some form. Therefore, the sleep state evaluation unit 43 can be a unit that causes the printer to print the discrimination result or a unit that stores the discrimination result in the storage device.

  The second frequency value calculation unit 44, from the turn angle related to the turnover behavior made in the evaluation target time zone for the first time width, among the plurality of turnover angles in the turnover angle information generated by the turnover angle information generation unit 40, This is a unit that executes the frequency value calculation process for calculating the frequency value Z (A) for each angle value A for each of a plurality of evaluation target time zones with different start times.

  The second calculation / output unit 45 includes a plurality of frequency values calculated by the frequency value calculation process related to the evaluation target time zone for each of the plurality of evaluation target time zones for which the function calculation processing has been performed by the second frequency value calculation unit 44. This is a unit that calculates the turnover frequency factor α from the frequency value Z (A) and outputs the turnover frequency factor α calculated for each evaluation target time zone in a form in which the correspondence relationship with the evaluation target time zone is known. The second calculation / output unit 45 according to the present embodiment also outputs the turnover frequency factor α to the display 22 (the turnover frequency factor α is displayed on the screen of the display 22 in a form in which the correspondence relationship with the evaluation target time zone is known. Unit). However, the second calculation / output unit 45, like the sleep state evaluation unit 43, also has a unit that causes the printer to print information indicating the correspondence relationship between the turnover frequency factor α and the evaluation target time zone, and the information Can be stored as a unit in the storage device.

  Hereinafter, the various functions described above of the information processing apparatus 20 according to the present embodiment will be described more specifically together with a method for using the sleep state evaluation system, using a flowchart and the like.

  When the sleep state of a subject is evaluated using this sleep state evaluation system (see FIG. 1A), first, the subject behavior measurement device 10 is connected to the information processing device 20, and the subject behavior measurement device 10 is provided with an acceleration recording cycle. Processing to set is performed. Note that the default value of the acceleration recording period of the subject behavior measuring apparatus 10 is 10 ms. This default value is a value that can accurately determine the turnover angle (rotation angle around the body axis in each turnover action (turnover action, action to turn over) performed by the subject) for a general subject. . Therefore, the process of setting (changing) the acceleration recording cycle is usually omitted.

  After changing the recording cycle setting or not changing the recording cycle, the subject behavior measuring device 10 is fixed to the subject by a dedicated belt or the like, and the slide switch of the subject behavior measuring device 10 is turned on. Is called. Then, in this state, the subject takes a sleep, and the slide switch is turned off after the subject wakes up.

  Thereafter, the subject behavior measuring apparatus 10 is removed from the dedicated belt or the like and connected to the information processing apparatus 20.

  The computer on which the CPU 31 executes the sleep state evaluation program 35 (that is, the information processing apparatus 20) operates in a state where it accepts input of various instructions from the operator.

Then, the information processing apparatus 20 processes a certain file on the storage unit 12 of the subject behavior measuring apparatus 10 (a file holding the current time, the recording cycle, and the measurement results of acceleration in three directions at various times) by the operator. When instructed to do so, the analysis processing of the procedure shown in FIG. 2 is executed. Although not described in detail, the information processing apparatus 20 also has a function of performing this analysis processing on a file obtained by copying a file stored in the storage unit 12 to another storage device. Further, the part / function of the information processing device 20 that performs the processing of steps S101 to S103 of this analysis processing is the function of the CPU 31 corresponding to the turning angle information generation unit 40 described above, and step S104 of the information processing device 20 is performed. The part / function for performing the process is the function of the CPU 31 corresponding to the frequency value calculation unit 41 described above. Furthermore, the part / function of the information processing apparatus 20 that performs the processing of steps S105 and S106 is the function of the CPU 31 corresponding to the calculation / output unit 42 or the calculation / output unit 42 and the sleep state evaluation unit 43.

As shown in FIG. 2, during this analysis process, the information processing apparatus 20 (the CPU 31 in the information processing apparatus 20) first operates from the storage unit 12 (or other storage device) of the subject behavior measurement apparatus 10. The content of the file designated by the user is read, and based on the read acceleration group, recording cycle, etc., the average acceleration X (T _n ) per second in the X direction and the average acceleration Y (T _n per second in the Y direction) ), An average acceleration Z (T _n ) per second in the Z direction is calculated (step S101). Note that in _{T n} in X _{(T n)} or the like, after the start of measurement, by the n-1 th second n seconds th (n = 1, 2, 3 ...) to the time zone (second) is there.

  In short, the acceleration measurement result by the subject behavior measuring apparatus 10 does not result from the subject's rollover behavior (the subject's complete rollover operation or an attempt to roll over) (detection result of acceleration when the body shakes finely) And noise). And although details will be described later, since this analysis process is a process for evaluating the sleep state of the subject based on the frequency of the turnover behavior, by averaging the acceleration, detailed information is obtained from the information to be processed thereafter. It removes information about movements that the body does not turn over, such as trembling.

  The information processing apparatus 20 that has finished the process of step S101 obtains the falling angle Fall and the rotation angle Turn at each time by the following equations (step S102).

Here, arccos is an arc cosine function, and arctan is an arc tangent function.

  As already described (defined), X, Y, and Z are the left-right direction (left is a plus direction), the up-down direction (up is a plus direction), and the front-back direction (front is a plus direction), respectively. Accordingly, in step S102, the angle shown in FIG. 3A, that is, the rotation angle around the subject's body axis (“0” when the front of the subject's body is directly above) is calculated as the rotation angle Turn. Will be. In step S102, the angle shown in FIG. 3B, that is, the elevation angle of the subject is calculated as the fall angle Fall.

  When the process of step S102 is completed, data (time-series rotation angle group and time-series fall angle group) having contents as shown in FIG. 4 is stored in the information processing apparatus 20 (in this embodiment, the information processing apparatus). 20 RAM).

  The information processing apparatus 20 that has prepared such data therein calculates the turning angle, which is the rotation angle of each turning behavior performed by the subject during sleep, from the rotation angle calculated for each time with reference to the fall angle. The process (step S103) to perform is performed.

  Details of the processing in step S103 will be described below.

  In the process of step S103, basically, the absolute value of the difference between the rotation angle of each local minimum point and the rotation angle of the local maximum point immediately after each local minimum point is calculated as the turning angle of each local minimum point, and each local maximum point is calculated. And the absolute value of the difference between the rotation angle of the local maximum point and the rotational angle of the local maximum immediately after each local maximum point is calculated as the turning angle of each local maximum point. Here, as schematically shown in FIG. 5, the minimum point and the maximum point are times smaller than the rotation angles of the preceding and succeeding times and times larger than the rotation angles of the preceding and following times, respectively. . However, in the process of step S103, the turning angle is calculated according to the above procedure only for the rotation angle at which the falling angle at the same time is a predetermined angle (70 degrees in this embodiment) or more. Yes.

  That is, in the process of step S103, basically, an operation that can be said to be turned over even by a general standard, and an operation that slightly rotates the body that cannot be said to be turned up by a general standard are regarded as "rolling behavior". This is a process of calculating the rotation angle around the body axis of the subject at each turning behavior as the turning angle.

  Then, when the subject has never woken up while sleeping, the rotation angle (turning angle) for each turning behavior can be calculated by the above procedure. However, the subject's body also rotates around the body axis when the subject wakes up while sleeping (when the subject does not turn over). Therefore, when the subject wakes up several times during bedtime, in the above procedure, the rotation angle around the body axis of the subject at the time of behavior other than the turning behavior is calculated as the turning angle.

  And it can be judged from a fall angle whether the subject woke up. For this reason, the processing in step S103 is performed as described above.

  The information processing apparatus 20 that has finished the process of step S103 determines that the value is A for each of a plurality of predetermined angle values A (in this embodiment, an angle for each degree from 10 degrees to 45 degrees). The cumulative sum of the turning angles that are greater than or equal to degrees is calculated as a frequency value Z (A) (step S104).

  That is, in step S104, the information processing apparatus 20 performs a process of calculating the frequency value Z (A) by using the above-described equation (1) for each of a plurality of predetermined angle values A.

Next, the information processing apparatus 20 calculates the coefficients α and β so that the calculated frequency values Z (A) are approximated by the following regression equation (step S105).

  Here, the reason why the processing having the above contents is adopted as the processing of steps S105 and S106 will be described.

  When developing this sleep state evaluation system (mainly the sleep state evaluation program 35), information on the behavior during sleep of various subjects (subjects with normal sleep, subjects with insomnia, etc.) (acceleration in three directions) Collecting and analyzing the collected information and the relationship between the sleep state of the subject is performed. As a result, the following is known.

When the logarithmic value of the frequency value Z (A) described above is plotted against the A value, regardless of the subject, the graph as shown in FIG. 6, that is, log A in the region where the A value is 10 degrees to 45 degrees. A graph in which (A) changes linearly with respect to A is obtained (that is, when the A value is in the range of 10 to 45 degrees, it can be approximated by Z (A) in the above regression equation). The graph shown in FIG. 6 is obtained by calculating the frequency value Z (A) from the data (turning angle group) shown in FIG.

The value of the logZ (A) axis intercept of the straight line portion of the graph (FIG. 6) in which the logarithmic value of the frequency value Z (A) is plotted against the A value (hereinafter referred to as the rollover frequency factor α) and the inverse of the slope There is a correlation as shown in FIG. 8 between the sleep energy (hereinafter referred to as “rolling energy β”) and the sleep state of the subject.

  The correlation between the turnover frequency factor α and the turnover energy β shown in FIG. 8 and the sleep state of the subject is obtained by combining the experimental results as shown in FIG. 9 as an example.

  Specifically, FIG. 9 is a diagram showing experimental results for a total of four subjects, two healthy subjects and two Parkinson's disease patients (hereinafter also referred to as PD patients). The turnover frequency factor shown in FIG. 9 is a value (α / sleep time) converted into a numerical value per unit time.

  As is clear from FIG. 9, both of the healthy persons (*) have a turnover frequency factor α of 200 or more and a turnover energy β of 60 or more, and both the turnover frequency factor α and the turnover energy β are large. ing. One PD patient (◯, Δ, □) has a rollover frequency factor α of 100 or less and a rollover energy β of 30 or less, both of which are small. In addition, the calculation results (、, Δ, □) of the turnover frequency factor α and the turnover energy β for PD patients indicate reproducible values that do not depend on the measurement date.

  Another PD patient (●) has a very low turnover energy β, but has a very high turnover frequency factor α. In this way, the PD patient who cannot move is less likely to turn over, and conversely, if the patient cannot fall asleep, the turnover frequency is increased.

  Since the above has been found from the experimental results, the coefficients α (rolling frequency factor) and β (rolling energy) of the regression equation are calculated in step S105. Further, the frequency value Z (A) value outside the range of 10 degrees to 45 degrees is unnecessary for the calculation of α and β. Therefore, the frequency value Z (A) is calculated only for each angle from 10 degrees to 45 degrees in step S106.

  The information processing apparatus 20 that has finished the process of step S106 displays the value of the turnover frequency factor α on the screen of the display 22 (step S106). The value of the turnover frequency factor α of the subject who cannot sleep well is a high value (usually about 400) (see FIGS. 8 and 9). Therefore, the operator can grasp the sleep state of the subject from the turnover frequency factor α shown on the screen of the display 22.

  When a predetermined instruction is input, the information processing apparatus 20 displays information (message) indicating the sleep state of the subject (see FIG. 8) determined from the α value on the screen of the display 22 in step S106. indicate. Furthermore, when another predetermined instruction is input, the information processing apparatus 20 displays the sleep state classification of the subject determined from the α value and the β value on the screen of the display 22 (steps A to 8 in FIG. 8). Information (message) indicating F) is displayed. Therefore, the operator of the information processing device 20 can grasp what state the subject's sleeping state is by using this function.

  Then, the information processing apparatus 20 ends the analysis process (the process of FIG. 2) when instructed to end the process (or start the process for data in another file).

  In addition, when the information processing apparatus 20 is instructed by the operator to display the time dependency of the turnover frequency factor α for a certain file on the storage unit 12 (or another storage apparatus), The second analysis process of the procedure shown in FIG. Note that the function of the information processing apparatus 20 that performs the processes of steps S201 to S203 of the second analysis process is the function of the CPU 31 corresponding to the turning angle information generation unit 40 described above. The functions of the information processing apparatus 20 that perform the processes of steps S204 and S205 and the function of performing the process of step S206 are functions of the CPU 31 that correspond to the second frequency value calculation unit 44 and the second calculation / output unit 45, respectively. It is.

  The processes of steps S201 to S204 of the second analysis process are the same as the processes of steps S101 to S104 described above.

  The process of step S205 includes a plurality of evaluation objects for the same time width Tw (> ΔT, for example, 1 hour), in which the start time is shifted by a predetermined time ΔT (for example, 10 minutes) for all time zones in which acceleration is measured. This is a process of virtually dividing into time zones and performing the same processing as the processing of step S105 described above for each divided evaluation target time zone.

  And the process of step S206 of a 2nd analysis process is a process which displays the turnover frequency factor (alpha) calculated about each evaluation object time slot | zone on the screen of the display 22 as a graph as shown in FIG. . The graph actually displayed on the screen of the display 22 does not display the arrow and the character string “REM sleep” shown in FIG.

  In general, turning over is often seen when switching between non-REM sleep and REM sleep. Therefore, it can be estimated that the state of the subject in the time zone in which the turnover frequency factor α is particularly large in the processing result of the second analysis processing (FIG. 11) is the state at the start of REM sleep or the state in REM sleep. . Moreover, it can be estimated that the subject is in a deeper sleep state in a time zone in which the turnover frequency factor α is small.

  Further, as schematically shown in FIG. 12, when the person does not fall asleep, the turnover frequency factor α changes over time, and when the person cannot take a deep sleep, the turnover frequency factor α does not change much over time. The value is in the vicinity of 500. Furthermore, when good sleep is achieved, the turnover frequency factor α rises and falls within the range of about 0 to 500 with the passage of time, and the turnover frequency factor α of Parkinson's disease patients is low with little time change. Take the value. Therefore, it can be understood from the processing result of the second analysis process (FIG. 11) what kind of sleep the subject is taking.

  As described above in detail, the sleep state evaluation system according to the present embodiment corresponds to the number of executions of the subject's turn-over behavior (the turn-over operation, the operation to turn over) based on the behavior information of the subject during sleep. It has a function of calculating and outputting the turnover frequency factor α. The turnover frequency factor α is a value that has a correlation with the sleep state of the subject and a value that can be uniquely determined without setting a threshold value.

  Therefore, if the sleep state evaluation system according to the present embodiment is used, the sleep state of the subject can be evaluated in such a way that the sleep state of the subject is not erroneously evaluated due to a threshold setting error.

<Modification>
Various modifications can be made to the sleep state evaluation system according to the embodiment described above. For example, with the information processing apparatus 20 as each Z (A), as schematically shown in FIG. 13, the maximum value of the turn angle in the time zone in which the turn behavior with the turn angle of the angle A or more is continuously performed. It can be transformed into a device for calculating the sum of (● in the figure).

Incidentally, the sum of the maximum value of such a turn angle, for example, greater than before and after the turn angle, and its value is earlier occurrence time t _i of turn behavior of the large turn angle W (t _i) than A If you specify in order from the (or later), and then add all the specified W (ti) (i = 1 to n: n is the total number of the specified turning angle) as in the following formula, Can be obtained.

The information processing apparatus 20 may be transformed into an apparatus that calculates each frequency value Z (A) from the above-described P (x) (the number of turn angles at which x and its value match) by the following expression. I can do it.

In other words, the information processing device 20 can be transformed into a device that calculates the total number n of the turning angles having a value of A or more as each frequency value Z (A) as in the following equation.

Further, the information processing apparatus 20 can be modified to use the following Pareto function as a regression equation for obtaining the rollover frequency factor α and the rollover energy β.

The information processing apparatus 20 can be transformed into a regression equation for obtaining the rollover frequency factor α and the rollover energy β into the following using a cut Pareto function,

  Further, the information processing apparatus 20 calculates more frequency values Z (A) in the process of step S104 (or S204), and calculates the rollover frequency factor α and the rollover energy β during the process of step S105 (or S205). The range of the frequency value Z (A) used in the above can be shifted back and forth to change to a device that calculates the turnover frequency factor α and the turnover energy β with the smallest difference (error).

A system in which the process up to step S101, the process up to step S102, or the process up to step S103 is performed on the subject behavior measuring apparatus 10 side, and the subsequent process is performed on the information processing apparatus 20 side. It can also be transformed into

  The information processing device 20 of the sleep state evaluation system is a device that does not have the function of performing the second analysis process (FIG. 10) (the device that does not have the second frequency value calculation unit 44 and the second calculation / output unit 45). It can also be transformed. The information processing apparatus 20 can be transformed into an apparatus that allows the operator to set (change) the average time in the processing of step S102 and / or step S202.

  In addition, the above-mentioned turnover frequency factor α is a value that can be calculated as long as the turnover angle at each turnover behavior of the subject can be understood. If the rotation angle around the body axis at each time is known, the value can be calculated. Therefore, the subject behavior measuring apparatus 10 may be an apparatus including an inertial sensor other than the inertial sensor 11 (three-axis acceleration sensor) described above. As the inertial sensor 11 other than the triaxial acceleration sensor that can detect the rotation angle around the body axis of the subject, a gyro sensor and a speed sensor of a biaxial acceleration sensor can be exemplified. The inertial sensor 11 may be a combination of one or two axis acceleration sensors.

  The inertial sensor 11 is not limited to the inertial sensor. The inertial sensor 11 captures the subject with a camera, analyzes the captured image and obtains the motion of the subject as an operation signal, and the movement of the marker attached to the subject is optical or mechanical. A device that detects an operation signal by a magnetic tracker (sensor), that is, a so-called motion capture device may be used.

  In addition, the sleep state evaluation system can be transformed into a system in which a measurement cycle such as acceleration by the subject behavior measuring apparatus 10 cannot be set. In addition, when transforming the sleep state evaluation system into such a system, the measurement period such as acceleration is set to a value of about 1 ms to 1 s, particularly about 5 ms to 50 ms so that the turning angle can be accurately calculated. (Sampling frequency such as acceleration is preferably about 1 to 1000 Hz, particularly about 20 to 200 Hz).

In addition, in the sleep state evaluation system, communication between the subject behavior measurement device 10 and the information processing device 20 is performed wirelessly, or a part of the unit (functional block) group of the information processing device 20 illustrated in FIG. Or, ASIC etc. (application specific integrated circuit)
Of course, things that you may want to do in are natural.

DESCRIPTION OF SYMBOLS 10 ... Subject behavior measuring apparatus 11 ... Inertial sensor 12 ... Memory | storage part 13 ... Interface circuit 14 ... Microprocessor 18 ... Cable 20 ... Information processing apparatus 21 ... Input device 22 ... Display 23 ... Computer main body 24 ... Storage unit 31 ... CPU
35 ... Sleep state evaluation program 40 ... Rolling angle information generation unit 41 ... Frequency value calculation unit 42 ... Calculation / output unit 43 ... Sleep state evaluation unit 44 ... Second frequency value calculation 45: Second calculation / output unit

Claims (14)

Based on a plurality of turn angles that are rotation angles around the body axis in each turn behavior performed by the subject during sleep, execution of the turn behavior of the subject with a turn angle of A degrees or more for each of a plurality of angle values A A frequency value calculation unit for calculating a frequency value Z (A) representing the frequency;
A calculation / output unit that calculates and outputs a turnover frequency factor α for the subject based on a plurality of frequency values Z (A) calculated by the frequency value calculation unit for the plurality of angle values A;
An information processing apparatus comprising: The frequency value Z (A) is a value represented by the following expression when the number of the turn angle whose value is x among the plurality of turn angles is expressed as P (x).
The information processing apparatus according to claim 1. 2. The information processing according to claim 1, wherein the frequency value Z (A) is a sum of the maximum values of the turning angle in each time zone in which the turning behavior with a turning angle of A degrees or more is continuously performed. apparatus. The calculation / output unit calculates α and β so that each Z (A) calculated by the frequency value calculation unit is approximated by the following regression equation, and the calculated α is turned over to the turn Output as frequency factor α
The information processing apparatus according to claim 1, wherein the information processing apparatus is an information processing apparatus. The information processing apparatus according to claim 4, wherein the calculation / output unit outputs the calculated α as the turnover frequency factor α and outputs the calculated β as the turnover energy β. A sleep state evaluation unit that determines which sleep state of the subject is a plurality of predetermined sleep states based on the turnover frequency factor α calculated by the calculation / output unit, and outputs a determination result The information processing apparatus according to claim 4, further comprising: A frequency value calculation process for calculating the frequency value Z (A) for each angle value A from the turn angle related to the turnover behavior made in the evaluation time zone corresponding to the first time width in the plurality of turn angles, A second frequency value calculation unit that executes for each of a plurality of evaluation target time zones with different start times;
For each of the plurality of evaluation target time zones, the turnover frequency factor α is calculated from the plurality of frequency values Z (A) calculated by the frequency value calculation processing related to the evaluation target time zone, and for each evaluation target time zone A second calculation / output unit for outputting the calculated turnover frequency factor α in a form in which the correspondence relationship with the evaluation target time zone is understood;
The information processing apparatus according to any one of claims 1 to 6, further comprising: Based on rotation angle information including a rotation angle around the body axis of the subject who is sleeping for each of a plurality of times, a turn angle information generating unit that generates a turn angle information including a plurality of turn angles is further provided,
The frequency value calculation unit calculates the frequency value Z (A) for each angle value A based on the plurality of turn angles in the turn angle information generated by the turn angle information generation unit. The information processing apparatus according to any one of claims 1 to 7. The rotation angle information includes a fall angle that is an inclination angle of the body axis of the subject at each time for each of the plurality of times,
The turning angle information generating unit generates the turning angle information only from a rotation angle in which the fall angle is an angle within a specified range in the rotation angle information. Information processing device. A turnover angle information generating unit that generates turnover angle information including a plurality of turnover angles from the acceleration information in three directions for the sleeping subject recorded in time series by the motion sensor, and further includes:
The frequency value calculation unit calculates the frequency value Z (A) for each angle value A based on the plurality of turn angles in the turn angle information generated by the turn angle information generation unit. The information processing apparatus according to any one of claims 1 to 9. Computer
Based on a plurality of turn angles that are rotation angles around the body axis in each turn behavior performed by the subject during sleep, execution of the turn behavior of the subject with a turn angle of A degrees or more for each of a plurality of angle values A A frequency value Z (A) representing the frequency is calculated,
A sleep state evaluation method comprising: calculating and outputting a turnover frequency factor α of the subject based on a plurality of frequency values Z (A) calculated for the plurality of angle values A. On the computer,
Based on a plurality of turn angles that are rotation angles around the body axis in each turn behavior performed by the subject during sleep, execution of the turn behavior of the subject with a turn angle of A degrees or more for each of a plurality of angle values A A process of calculating a frequency value Z (A) representing the frequency;
A sleep state evaluation program characterized by performing a process of calculating and outputting the turnover frequency factor α of the subject based on a plurality of frequency values Z (A) calculated for the plurality of angle values A. An evaluation system including a subject behavior measuring device and an information processing device for measuring the behavior of a sleeping subject,
The information processing apparatus includes:
Based on a plurality of turn angles that are rotation angles around the body axis in each turn behavior performed by the subject during sleep, determined from the measurement results of the subject behavior measurement device, for each of a plurality of angle values A, A frequency value calculation unit that calculates a frequency value Z (A) that represents the execution frequency of the turnover behavior of the subject whose turnover angle is A degrees or more;
A calculation / output unit that calculates and outputs a turnover frequency factor α for the subject based on a plurality of frequency values Z (A) calculated by the frequency value calculation unit for the plurality of angle values A;
Comprising
An evaluation system characterized by that. The subject behavior measuring device is
The evaluation system according to claim 13, wherein the evaluation system is an apparatus that measures acceleration in three directions of the subject.