Systems and methods are presented for monitoring brain pulsatility. A change in volume of the brain is estimated based at least in part on an output of a non-contact, surface measuring sensor (e.g., a distance sensor or a camera). A metric indicative of brain pulsatility is then calculated based at least in part on a ratio of the estimated change in volume of the brain relative to a change in arterial blood pressure.

A photoplethysmogram (PPG) sensor includes a pixel array that collects light, a pixel sampler that converts the light collected through the pixel array into a plurality of pixel data, an effective area determiner that determines an effective area and a non-effective area of the pixel array based on the pixel data, a power controller that is operable to cut off power to the non-effective area of the pixel array, and a PPG data generator that generates PPG data from pixel data corresponding to the effective area among the pixel data.

A photoplethysmogram (PPG) sensor includes a pixel array that collects light, a pixel sampler that converts the light collected through the pixel array into a plurality of pixel data, an effective area determiner that determines an effective area and a non-effective area of the pixel array based on the pixel data, a power controller that is operable to cut off power to the non-effective area of the pixel array, and a PPG data generator that generates PPG data from pixel data corresponding to the effective area among the pixel data.

Disclosed are one or more proximity sensors. At least one of the proximity sensors includes a first dielectric layer, an electrically conductive layer, and an electrode. The first dielectric layer includes an inner surface and an outer surface. The electrically conductive layer is positioned proximate to one of the inner surface or the outer surface of the first dielectric layer. The electrode includes an outer surface. The outer surface of the electrode is positioned proximate the inner surface of the first dielectric layer. The outer surface of the electrode and the electrically conductive layer define a gap.

A system includes a collar that is worn around a neck of the user. A stimulator is coupled to the collar such that the stimulator is positioned adjacent to an airway of the user. The sensor is coupled to the collar and configured to generate data associated with the airway of the user. The memory is coupled to the collar and storing machine-readable instructions. The control system is coupled to the collar and includes one or more processors configured to execute the machine-readable instructions to determine, based at least on an analysis of the generated data, that the user is currently experiencing an apnea event. In response to the determination, the control system causes the stimulator to provide electrical stimulation, at a first intensity level, to one or more muscles of the user that are adjacent to the airway to aid in stopping the apnea event.

A vascular baroreflex-related sympathetic activity (VBRSA) detection device, a VBRSA detection program, and a VBRSA detection method capable of detecting in a simple and non-invasive manner VBRSA, which is sympathetic nervous activity of a blood vessel involved in a baroreflex function, are provided. The VBRSA detection device detects the VBRSA based on pulse wave data on a biological artery and a beat interval corresponding to the pulse wave data. The VBRSA detection device includes a VBRSA-series detecting unit that detects, as a VBRSA series indicative of VBRSA, a series where, from among the series in which the beat interval increases or decreases by n (n is a natural number 3 or more) beats consecutively, a correlation coefficient for the beat interval and pulse wave data is greater than any positive threshold up to the (n-1)-th beat and the correlation coefficient at the n-th beat falls to or below the threshold.

A vascular baroreflex-related sympathetic activity (VBRSA) detection device, a VBRSA detection program, and a VBRSA detection method capable of detecting in a simple and non-invasive manner VBRSA, which is sympathetic nervous activity of a blood vessel involved in a baroreflex function, are provided. The VBRSA detection device detects the VBRSA based on pulse wave data on a biological artery and a beat interval corresponding to the pulse wave data. The VBRSA detection device includes a VBRSA-series detecting unit that detects, as a VBRSA series indicative of VBRSA, a series where, from among the series in which the beat interval increases or decreases by n (n is a natural number 3 or more) beats consecutively, a correlation coefficient for the beat interval and pulse wave data is greater than any positive threshold up to the (n-1)-th beat and the correlation coefficient at the n-th beat falls to or below the threshold.

An electronic device includes an information acquisition unit, a display information determination unit, and a display control unit. The information acquisition unit acquires first pulse wave information indicating a pulse wave of a part of a body based on image information of the body in a first image obtained by imaging at least the part of the body, and acquires second pulse wave information indicating a pulse wave of a part of the body based on image information of the body in a second image obtained by imaging the part of the body after the first image has been obtained. The display information determination unit determines a display range of a display color of a display image or brightness corresponding to a blood flow variation of a part of the body based on first pulse wave information and second pulse wave information. The display control unit controls display of the display image by the display color determined based on the display range or brightness and the second pulse wave information.

An electronic device includes a sensor, a memory, and a display, and a processor. The processor is configured to determine bio-information and blood pressure information of a user measured through the sensor, determine reliability of calibration of the blood pressure information, based on at least one of elapsed time of the calibration, the bio-information, and the blood pressure information, determine, based on the reliability of the calibration, whether an event associated with the calibration occurs, and display a user interface (UI) to request another calibration, through the display, when the event is determined to have occurred.

An electronic device includes a sensor, a memory, and a display, and a processor. The processor is configured to determine bio-information and blood pressure information of a user measured through the sensor, determine reliability of calibration of the blood pressure information, based on at least one of elapsed time of the calibration, the bio-information, and the blood pressure information, determine, based on the reliability of the calibration, whether an event associated with the calibration occurs, and display a user interface (UI) to request another calibration, through the display, when the event is determined to have occurred.