JP2008173280A - Cough detecting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cough detection system which enables the better detection of coughs. <P>SOLUTION: Information on a subject's blood stream is sensed with a pulse oximeter (blood stream detection part) 10 and the subject's coughs are detected with a cough detection part 20 based on the information on the blood stream detected. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cough detection system.

  Cough is a common symptom of respiratory diseases (particularly asthma, chronic obstructive pulmonary disease, bronchitis, etc.). The current situation is that cough diagnosis relies on an interview, but the patient does not necessarily have cough at the time of the examination, and the doctor can only hear the subjective symptoms from the patient. Moreover, even if the patient remembers the symptoms at the time of awakening during the day, the cough during sleep is limited to expressions such as severe cough and inability to sleep. Therefore, there has been a problem that objective evaluation cannot be performed and effective treatment cannot be performed.

  Therefore, in order to perform an objective evaluation of cough, a technique for detecting cough by a voice uttered by a subject (see Patent Document 1), or a technique for detecting cough by an operation of the subject's throat (Patent Document 2). For example).

  The technique described in Patent Document 1 is a technique for detecting and monitoring cough by attaching a microphone near the subject's sternum and identifying and extracting a cough voice signal from a voice signal input from the microphone. is there.

In addition, the technique described in Patent Document 2 determines whether or not a cough is present by attaching an acceleration sensor to the subject's throat and comparing a signal obtained from the acceleration sensor with a pre-registered cough signal. It is a technology to do.
JP-A-7-376 Japanese Patent Laid-Open No. 9-98964

  However, in the technique of detecting cough by the sound uttered by the subject, it is difficult to distinguish cough when a sound similar to cough is generated, and there is a possibility that cough is erroneously detected.

  In addition, in the technique of detecting cough by the operation of the subject's throat or the like, it is difficult to accurately detect cough only by the operation of the subject, and erroneous detection may occur.

  Therefore, the present inventors have studied the provision of a technique that can solve the above-described problem of false detection and can perform good cough detection. The present inventors have found that when coughing, changes in blood flow and blood pressure appear, a pulse oximeter or the like can be used to detect a subject's cough, and a good cough can be detected. . If an objective evaluation of the subject's cough can be performed using a pulse oximeter or the like, it is not necessary to attach a microphone, an acceleration sensor, or the like to the subject, and the burden on the subject can be reduced. The subject who detects cough is often a patient, and it is convenient that the patient's medical condition may be confirmed by a pulse oximeter, blood pressure monitor, electrocardiograph or the like.

  Accordingly, an object of the present invention is to provide a cough detection system capable of detecting cough satisfactorily.

In order to achieve the above object, the cough detection system according to the present invention comprises:
A blood flow detector that detects information about the blood flow of the subject;
A cough detection unit for detecting a cough of the subject based on information on blood flow detected by the blood flow detection unit;
It is characterized by having.
Further, the cough detection system according to the present invention,
An action potential measurement unit that measures temporal changes in action potentials in the subject's heart;
A cough detection unit for detecting a cough of the subject based on a temporal change in the action potential measured by the action potential measurement unit;
It is characterized by having.

Further, the cough detection system according to the present invention,
A blood flow detector that detects information about the blood flow of the subject;
A subject detection unit for detecting a voice emitted from the subject or a body movement of the subject;
A cough detection unit for detecting a cough of the subject based on at least one of information on the blood flow detected by the blood flow detection unit or a result detected by the subject detection unit;
It is characterized by having.

Further, the cough detection system according to the present invention,
An action potential measurement unit that measures temporal changes in action potentials in the subject's heart;
A subject detection unit for detecting a voice emitted from the subject or a body movement of the subject;
A cough detection unit for detecting a cough of the subject based on at least one of a temporal change in the action potential measured by the action potential measurement unit or a result detected by the subject detection unit;
It is characterized by having.

  In the present invention, “information on the blood flow of a subject” refers to information obtained from a pulse oximeter, an electrocardiograph, a sphygmomanometer, etc., shown in the following best mode for carrying out the invention. In this way, it represents physical characteristics of blood flow itself, characteristic information for attracting blood flow, characteristic information attracted from blood flow, and the like.

  According to the cough detection system according to the present invention, cough can be detected satisfactorily.

  Moreover, according to the cough detection system according to the present invention, the cough detection accuracy can be improved by performing cough detection using a plurality of detection methods in combination.

  FIG. 1 is a configuration diagram of a cough detection system using a pulse oximeter, and shows a typical configuration.

  The cough detection system 1 includes a pulse oximeter 10 and a cough detection unit 20, and the pulse oximeter 10 is connected to the cough detection unit 20 via a communication medium L. This communication medium L may be wired or wireless. When connected wirelessly, the chance of giving unnecessary noise can be reduced, and restrictions on the behavior of the subject can be reduced.

  The pulse oximeter 10 that functions as a blood flow detection unit detects information related to the blood flow of the subject (specifically, information related to the blood flow of the subject). More specifically, the pulse oximeter 10 irradiates a plurality of lights having different wavelengths from the surface of the skin, detects reflected light signals of the plurality of lights or transmitted light of the plurality of lights, and detects the detected signals. The arterial oxygen saturation SpO2 is calculated. The time for one cough is approximately 1 second or less, and the temporal resolution of detection by the pulse oximeter is preferably 1 Hz or more (more preferably 5 Hz or more, and further preferably 100 Hz or more).

  The probe 11 includes a light emitting element for infrared light, a light emitting element for red light (irradiation unit), and a light receiving element for infrared light and a light receiving element for red light (light receiving unit). Reflected light or transmitted light is converted into an electrical signal by the probe 11 and input to the head amplifier 12. An infrared DC signal and a red DC signal are output from the head amplifier 12. Next, the infrared AC component and the red AC component are extracted by the high-pass filter 14.

  The infrared DC signal and the red DC signal are amplified by the amplifier 13, and the infrared AC signal and the red DC signal are amplified by the amplifier 15. The amplified signals are input to the AD converter 16. The AD converter 16 converts an analog electric signal into a digital electric signal. The signal converted by the AD converter 16 is input to the cough detection unit 20 through the I / F 17.

  The cough detection unit 20 may be configured with a dedicated information processing apparatus or a general-purpose personal computer. If it is a personal computer, it is preferably a personal digital assistant (PDA) that can be easily carried.

  A CPU (Central Processing Unit) 22 controls the overall operation of the cough detection system 1 and is connected to a ROM (Read Only Memory) 23, a RAM (Random Access Memory) 24, and the like. The CPU 22 reads out various programs stored in the ROM 23 and develops them in the RAM 24 to control the operation of each unit. Further, the CPU 22 executes various processes according to the program expanded in the RAM 24, stores the processing results in the RAM 24, and causes the display unit 27 to display them. Then, the processing result stored in the RAM 24 is stored in a predetermined storage destination.

  The ROM 23 stores programs, data, and the like in advance, and this recording medium is composed of a magnetic or optical recording medium or a semiconductor memory.

  The external storage device 25 stores the processing results in the CPU 22 on a hard disk, DVD-R, CD-R, or the like.

  The input unit 26 has a function of inputting data to the cough detection unit 20.

  The infrared DC signal, red DC signal, infrared AC signal, and red AC signal input to the I / F 21 are input to the CPU 22, and the arterial oxygen saturation SpO2 is calculated by the CPU 22. The calculated result is displayed on the display unit 27.

  The pulse oximeter 10 detects information related to the blood flow of the subject. When the subject coughs, the waveform of the above-described infrared DC signal, infrared AC signal, or the like changes. This point will be described in detail with reference to FIG.

  FIG. 2 is an explanatory diagram showing the waveform of the infrared AC signal acquired by the pulse oximeter 10.

  The blood flow of the subject in a state where no cough has occurred is stable, and the infrared AC signal acquired by the pulse oximeter 10 has a stable waveform as shown in FIG. However, when a cough occurs, the blood flow of the subject is disturbed, and the infrared AC signal acquired by the pulse oximeter 10 shows a unique waveform as indicated by α in FIG. Therefore, if this unique waveform in the infrared AC signal is detected, the subject's cough can be detected with high accuracy.

  As a specific method for detecting cough, it is conceivable to detect based on waveform pattern authentication, waveform rising slope, waveform time width, waveform peak-to-peak value, and the like.

  In FIG. 2, the description is based on the infrared AC signal acquired by the pulse oximeter 10, but the waveform changes in the same way for other signals such as the red AC signal, the infrared DC signal, and the red DC signal. It is possible to detect cough based on

  FIG. 3 is a flowchart relating to an operation for detecting cough.

  The operation for detecting cough shown in FIG. 3 is executed by the CPU 22 based on the cough detection program in the ROM 33. It is assumed that an ID for identifying the subject is input in advance by the input unit 26.

  First, the CPU 22 determines whether or not an instruction to start cough detection is given from the input unit 26 (step S1). If it is determined that the start of cough detection is instructed (step S1; Yes), the CPU 22 observes the blood flow waveform (for example, the waveform of the infrared AC signal) acquired by the pulse oximeter 10 (step S2), and cough is detected. Perform the action to detect. As described above, the cough detection operation is detected based on the waveform pattern authentication, the waveform rising slope, the waveform time width, the waveform peak-to-peak value, and the like.

  If cough is detected (step S3; Yes), the detection result is stored in the external storage device 35 via the RAM 24 (step S4). If it is determined that the end of cough detection is not instructed (step S5; No), the process returns to step S2 and the observation of the blood flow waveform is continued.

  When there is an instruction to end cough detection (step S5; Yes), the operation for detecting a series of cough is ended. When the detection operation is finished, the result of cough detection is stored in the external storage device 25 in association with the subject, so that the appropriate number of coughs, the time zone when the cough occurred, etc. Treatment is possible.

  As described above, if a subject's cough is detected based on information about the blood flow of the subject, false detection can be reduced and cough can be detected satisfactorily.

  Next, a cough detection system that detects cough using an electrocardiograph will be described.

  FIG. 4 is a configuration diagram of a cough detection system using an electrocardiograph and shows a typical configuration.

  As shown in FIG. 4, the cough detection system 2 includes an electrocardiograph (action potential measurement unit) 30 that measures a temporal change in action potential in the subject's heart, and bioelectricity detected by the electrocardiograph 30. The cough detection unit 20 detects cough using a signal.

  An electrode unit 31 composed of a negative electrode, a positive electrode, and an indifferent electrode is brought into contact with a part of the subject's body to acquire an action potential in the subject's heart.

  The electric signal acquired by the electrode unit 31 is input to the amplifier 32. The amplifier 32 amplifies the input electric signal and outputs it to the high pass filter 33. The high pass filter 33 removes a noise component from the input electric signal and outputs it to the A / D converter 34. The A / D converter 34 converts the input analog electrical signal (biological electrical signal) into a digital electrical signal. The signal converted by the AD converter 34 is input to the cough detection unit 20 through the I / F 17.

  The configuration of the electrocardiograph 30 is an example, and any form such as a 12-dielectric electrocardiograph may be used as long as it can measure a temporal change in action potential in the subject's heart.

  The cough detection unit 20 in FIG. 4 has the same configuration as the cough detection unit 20 in FIG. The CPU 22 analyzes the input digital signal in real time and creates an electrocardiogram waveform. The electrocardiogram waveform is displayed on the display unit 27 and temporarily stored in the RAM 24.

  FIG. 5 is an explanatory diagram showing an electrocardiographic waveform acquired using the electrocardiograph 30.

  The heart rate of the subject in a state where cough has not occurred is stable, and the waveform of the bioelectric signal acquired using the electrocardiograph 30 is a stable waveform as shown in FIG. . However, when a cough occurs, the heartbeat of the subject is disturbed, and the bioelectric signal acquired using the electrocardiograph 30 shows a specific waveform as indicated by β and γ in FIG. Therefore, if this unique waveform in the waveform of the bioelectric signal is detected, the cough of the subject can be detected with high accuracy.

  As a specific method for detecting cough, it is conceivable to detect based on waveform pattern authentication, waveform rising slope, waveform time width, waveform peak-to-peak value, and the like.

  The operation for detecting cough in the cough detection system 2 using the electrocardiograph 30 is the same as the operation shown in FIG. When the cough detection operation based on the waveform of the bioelectric signal is finished, the cough detection result is stored in the external storage device 25 in association with the subject. Thus, an appropriate treatment or the like can be performed on the subject.

  As described above, if the subject's cough is detected based on the temporal change of the action potential in the subject's heart, false detection can be reduced and the cough can be detected satisfactorily.

  Next, a cough detection system that detects cough using a sphygmomanometer will be described.

  FIG. 6 is a configuration diagram of a cough detection system using a sphygmomanometer, and shows a typical configuration.

  The sphygmomanometer 40 measures the blood pressure by inserting a catheter 41 into the blood vessel of the subject.

  The catheter 41 and the pressure transducer 43 are connected via a pressure tube (not shown). A catheter 41 filled with physiological saline is inserted into the blood vessel of the subject through the pressure tube, and the pressure change of the physiological saline is detected by the pressure transducer 43. The change in the blood pressure value of the subject appears as a change in the physiological saline pressure.

  The flashback 42 is a pressurization type and pressurizes physiological saline to which heparin as an antithrombotic agent is added and supplies it to the pressure transducer 43 through a vinyl tube (not shown) to prevent blood coagulation in the pressure transducer 43. To do.

  The pressure change detected by the pressure transducer 43 is converted into a voltage value by the amplifier 44 and then amplified and input to the frequency filter 45. The frequency filter 45 extracts only the frequency necessary for measurement and inputs the obtained voltage value to the A / D converter 46. The AD converter 46 converts the input voltage value into a digital value. The voltage value converted by the AD converter 46 is input to the cough detection unit 20 through the I / F 47.

  The cough detection unit 20 in FIG. 6 has the same configuration as the cough detection unit 20 in FIG. The CPU 22 creates a waveform related to the blood pressure value based on the input voltage value. The waveform related to the blood pressure value is displayed on the display unit 27 and is temporarily stored in the RAM 24.

  The waveform of the blood pressure value acquired using the sphygmomanometer 40 is usually a stable waveform. However, when cough occurs, the blood pressure value is disturbed, and the waveform is unique like the waveform related to blood flow and the waveform of the bioelectric signal described above. Will be shown. Therefore, if this unique waveform in the waveform relating to the blood pressure value is detected, the cough of the subject can be detected with high accuracy.

  A specific method for detecting cough can be detected based on waveform pattern authentication or the like regarding the blood pressure value, and the operation of detecting cough in the cough detection system 3 using the sphygmomanometer 40 is the operation shown in FIG. It is the same.

  As described above, even if a subject's cough is detected based on information on the blood pressure of the subject, false detection can be reduced and cough can be detected satisfactorily.

  By the way, in consideration of the case where cough detection accuracy is further improved or the cough detection operation is disturbed, the voice or test performed by the subject to the cough detection system shown in FIG. 1, FIG. 4, FIG. It is also possible to include a function of detecting coughing based on a person's body movement. Hereinafter, a cough detection system that detects cough based on at least one of two waveforms will be described in detail.

  FIG. 7 is a configuration diagram of a cough detection system using a pulse oximeter and a voice detection unit, and shows a typical configuration.

  The pulse oximeter 10 is configured as described in FIG.

  The voice detection unit 50 functioning as a subject detection unit detects a voice uttered by the subject.

  The sound detection unit 50 includes a microphone 51 that converts input sound into a sound signal, an amplifier 52 that amplifies the sound signal converted by the microphone 51, a smoothing circuit 53 that smoothes the sound signal amplified by the amplifier 52, and smoothing An A / D converter 54 that converts the audio signal smoothed by the circuit 53 into a digital audio signal, and an I / F 55 that transmits the digital audio signal converted by the A / D converter 54 to the cough detection unit 20. It is composed of

  When sound is detected using the microphone 51, noise is generated when the human body or clothes and the microphone come into contact with each other. However, if the distance from the human body is too far away, the effect of external noise increases, so it is preferable to provide them as close as possible.

  In addition to the microphone, a piezo microphone or an accelerometer can be used to contact the pharynx or the like to detect sound by vibration. In this case, since it is in contact with the human body, the influence of external noise sound is small.

  The cough detection unit 20 is configured as described in FIG.

  The operation of detecting cough based on a signal such as an infrared AC signal acquired by the pulse oximeter 10 in the cough detection unit 20 is as described above. In addition to the operation, the cough detection unit 20 detects cough based on the audio signal acquired by the audio detection unit 50. The audio signal from the audio detection unit 50 is received by the I / F 21, and the CPU 22 processes the audio signal received by the I / F 21 according to a program.

  FIG. 8 is a diagram showing a waveform of an audio signal emitted by the subject.

  FIG. 8 shows the waveform of the audio signal Sv when the subject coughs, with the elapsed time on the horizontal axis and the signal level on the vertical axis. Cough is performed by storing air in the abdomen and calling the air all at once after closing the throat, and a strong sound is emitted in a short time. Therefore, as shown in the figure, in the case of cough, the rising slope θv of the audio signal Sv is steep and the time width Tv is shortened. Therefore, it is possible to detect whether the voice uttered by the subject is a cough based on the rising gradient θv and the time width Tv.

  In the cough detection system 4, it is conceivable to detect cough based on at least one of a signal related to blood flow acquired by the pulse oximeter 10 and a sound signal acquired by the sound detection unit 50. For example, when it is determined that noise has occurred in the voice signal acquired by the voice detection unit 50, the cough is detected from the signal related to blood flow acquired by the pulse oximeter 10. In this way, cough can be detected even when one of the pulse oximeter 10 and the voice detection unit 50 is troubled.

  It is also conceivable to detect cough on the basis of both the signals related to blood flow acquired by the pulse oximeter 10 and the audio signal acquired by the audio detector 50. If it is determined that a true cough has occurred when cough is detected simultaneously based on both signals, the accuracy of cough detection can be improved.

  Next, a cough detection system having a function of detecting cough based on a body motion signal of a subject instead of detecting cough based on an audio signal will be described.

  FIG. 9 is a configuration diagram of a cough detection system using a pulse oximeter and a body motion detection unit, and shows a typical configuration.

  The pulse oximeter 10 is configured as described in FIG.

  The body motion detection unit 60 that functions as a subject detection unit detects the body motion of the subject.

  The body motion detection unit 60 smoothes the body motion signal amplified by the accelerometer 61 that converts the input body motion into a body motion signal, the amplifier 62 that amplifies the body motion signal converted by the accelerometer 61, and the amplifier 62. Smoothing circuit 63 for converting the body motion signal smoothed by the smoothing circuit 63 into a digital body motion signal, and the digital body motion signal converted by the A / D converter 64 The I / F 65 is transmitted to the cough detection unit 20.

  The accelerometer 61 for detecting body movement is preferably provided in the abdomen, chest, or neck, and particularly preferably in the abdomen or chest. This is because the diaphragm and the chest move characteristically when coughing.

  The accelerometer 61 is preferably attached directly or indirectly to the human body with a double-sided tape or the like applied with an adhesive having low sensitivity to the skin. Further, it is preferable to provide a cover material or cushion material for preventing noise around the accelerometer 61.

  The cough detection unit 20 is configured as described in FIG.

  The operation of detecting cough based on a signal such as an infrared AC signal acquired by the pulse oximeter 10 in the cough detection unit 20 is as described above. In addition to the operation, the cough detection unit 20 detects cough based on the body motion signal acquired by the body motion detection unit 60. The body motion signal from the body motion detection unit 60 is received by the I / F 21, and the CPU 22 processes the body motion signal received by the I / F 21 according to a program.

  FIG. 10 is a diagram showing a waveform of a body motion signal generated by the subject.

  FIG. 10 shows the waveform of the audio signal Sm when the subject coughs, with the elapsed time on the horizontal axis and the signal level on the vertical axis. Cough is performed by storing air in the abdomen and calling the air all at once after closing the throat, and a strong sound is emitted in a short time. Therefore, as shown in the figure, in the case of cough, the rising slope θm of the audio signal Sm is steep and the time width Tm is shortened. Therefore, it is possible to detect whether the voice uttered by the subject is a cough based on the rising gradient θm and the time width Tm.

  In the cough detection system 5, it is conceivable to detect cough based on at least one of the signal related to blood flow acquired by the pulse oximeter 10 and the body motion signal acquired by the body motion detection unit 60. For example, when it is determined that noise has occurred in the body motion signal acquired by the body motion detection unit 60, the cough is detected from the signal related to the blood flow acquired by the pulse oximeter 10. In this way, cough can be detected even when either the pulse oximeter 10 or the body motion detection unit 60 has a problem.

  It is also conceivable to detect cough on the basis of both the signal relating to blood flow acquired by the pulse oximeter 10 and the body motion signal acquired by the body motion detector 60. If it is determined that a true cough has occurred when cough is detected simultaneously based on both signals, the accuracy of cough detection can be improved.

  FIG. 11 is a configuration diagram of a cough detection system 6 using an electrocardiograph and a voice detection unit.

  The cough detection system 6 is similar to the cough detection system 4 using the pulse oximeter and the voice detection unit shown in FIG. 7, and the bioelectric signal acquired by the electrocardiograph 30 and the voice signal acquired by the voice detection unit 50. The cough can be detected based on at least one of the signals, or the cough can be detected based on both signals.

  FIG. 12 is a configuration diagram of a cough detection system 7 using an electrocardiograph and a body motion detection unit.

  The cough detection system 7 is acquired by the bioelectric signal acquired by the electrocardiograph 30 and the body motion detection unit 60 in the same manner as the cough detection system 65 using the pulse oximeter and the body motion detection unit shown in FIG. Cough can be detected based on at least one of the body movement signals, or cough can be detected based on both signals.

  A cough detection system in which the sphygmomanometer 40 shown in FIG. 6 is installed instead of the electrocardiograph 30 shown in FIG. 11 or FIG. 12 is also conceivable, and the same effect as the cough detection system shown in FIG. 11 or FIG. .

  In addition, this invention is not limited to the said embodiment, Even if there exists a change and addition in the range which does not deviate from the summary of this invention, it is contained in this invention.

  In the “cough detection system” of the present invention, the elements constituting the system (for example, the paroximeter 10 and the cough detection unit 20) are separate from each other, and the elements constituting the system are integrated. A mode in which two devices are formed is also conceivable.

It is a block diagram of the cough detection system using a pulse oximeter. It is explanatory drawing which showed the waveform of the infrared AC signal acquired with the pulse oximeter. It is a flowchart figure regarding the operation | movement which detects a cough. It is a block diagram of a cough detection system using an electrocardiograph. It is explanatory drawing which showed the electrocardiogram waveform acquired using the electrocardiograph. It is a block diagram of a cough detection system using a sphygmomanometer. It is a block diagram of a cough detection system using a pulse oximeter and a voice detection unit. It is the figure which showed the waveform of the audio | voice signal which the subject emitted. It is a block diagram of the cough detection system using a pulse oximeter and a body motion detection part. It is the figure which showed the waveform of the body movement signal which the subject emitted. It is a block diagram of a cough detection system using an electrocardiograph and a voice detection unit. It is a block diagram of the cough detection system using a body motion detection part.

Explanation of symbols

1-7 Cough detection system 10 Pulse oximeter 20 Cough detection unit 30 Electrocardiograph 40 Sphygmomanometer 50 Voice detection unit 60 Body motion detection unit

Claims (10)

A blood flow detector that detects information about the blood flow of the subject;
A cough detection unit for detecting a cough of the subject based on information on blood flow detected by the blood flow detection unit;
A cough detection system comprising: The cough detection system according to claim 1, wherein the information related to blood flow is information related to blood flow. The blood flow detection unit includes an irradiation unit that irradiates a subject with light, and a light receiving unit that receives transmitted light or reflected light of the light irradiated by the irradiation unit. Cough detection system as described in. The cough detection system according to claim 1, wherein the information related to the blood flow is information related to blood pressure. An action potential measurement unit that measures temporal changes in action potentials in the subject's heart;
A cough detection unit for detecting a cough of the subject based on a temporal change in the action potential measured by the action potential measurement unit;
A cough detection system comprising: A blood flow detector that detects information about the blood flow of the subject;
A subject detection unit for detecting a voice emitted from the subject or a body movement of the subject;
A cough detection unit for detecting a cough of the subject based on at least one of information on the blood flow detected by the blood flow detection unit or a result detected by the subject detection unit;
A cough detection system comprising: The cough detection system according to claim 6, wherein the information related to the blood flow is information related to a blood flow. The blood flow detection unit includes an irradiation unit that irradiates light to the subject, and a light receiving unit that receives transmitted light or reflected light of the light irradiated by the irradiation unit. Cough detection system as described in. The cough detection system according to claim 6, wherein the information related to blood flow is information related to blood pressure. An action potential measurement unit that measures temporal changes in action potentials in the subject's heart;
A subject detection unit for detecting a voice emitted from the subject or a body movement of the subject; and
A cough detection unit for detecting a cough of the subject based on at least one of a temporal change in the action potential measured by the action potential measurement unit or a result detected by the subject detection unit;
A cough detection system comprising:

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