Abstract: A biopotential measurement device including a plurality of sensing electrodes and a controller is described. The plurality of sensing electrodes is adapted to measure one or more biopotential signals when the plurality of sensing electrodes is worn. The controller is coupled to the plurality of sensing electrodes and memory that stores instructions that when executed by the controller cause the biopotential measurement device to perform operations. The operations include collecting electrical signals over a first time period, each of the electrical signals associated with at least one of the plurality of sensing electrodes, mixing the electrical signals to generate a biopotential dataset that includes permutations of the electrical signals, and identifying a target biopotential signal included in the one or more biopotential signals based, at least in part, on the biopotential dataset.

Abstract: A method and monitor for monitoring vital signs. In one embodiment, the vital signs monitor includes a housing sized and shaped for fitting adjacent the ear of a wearer and an electronic module for measuring vital signs. The electronic module for measuring vital signs is located within the housing and includes a plurality of vital signs sensing modules in communication with a processor. The plurality of sensing modules includes at least two of the modules selected from the group of a ballistocardiographic (BCG) module, a photoplethysmographic (PPG) module, an accelerometer module, a temperature measurement module, and an electrocardiographic (ECG) module. In one embodiment, the processor calculates additional vital signs in response to signals from the plurality of vital signs sensing modules.

Abstract: The technology described in this document can be embodied in a method that includes obtaining a first pulse transit time (PTT) measurement and a second PTT measurement for a subject. The PTT represents a time taken by a pulse pressure wave traveling to the wrist of the subject. The first PTT is measured when the wrist of the subject is at a first height, and the second PTT is measured when the wrist of the subject is at a second height. The method also includes computing a hydrostatic difference in blood pressure as a function of the difference between the first height and the second height, and computing a calibration metric as a function of (i) the hydrostatic difference in blood pressure, and (ii) the difference between the first PTT and the second PTT.

Abstract: The technology described in this document can be embodied in a method that includes receiving optical data including information associated with a subject, and determining from the optical data, a first dataset and a second dataset. The first dataset represents time-varying color change at a first body part of the subject, and the second dataset represents time-varying characteristics at a second body part of the subject. The method includes identifying a first point in the first dataset, and a second point in the second dataset. The first point represents a time at which a pulse pressure wave traverses the first body part of the subject, and the second point represents a time at which the pulse pressure wave traverses the second body part of the subject. A pulse transit time (PTT) between the first and second body parts can be calculated as a difference between the first and second points.

Abstract: The technology described in this document is embodied in a method that includes processing data in a dataset that represents time-varying information about at least one pulse pressure wave propagating through blood in a subject acquired at a location of the subject. The method also includes determining whether one or more segments of the dataset were captured from a subject other than an expected subject by analyzing morphological features of the segments.

Abstract: The technology described in this document is embodied in a method that includes processing data in a first dataset that represents time-varying information about at least one pulse pressure wave propagating through blood in a subject acquired at a location of the subject. The method also includes providing information related to the data to a remote device.

Abstract: A weight-bearing device comprising: a weight-bearing surface configured to bear the weight of a subject; a first sensor module disposed in the device, the first sensor module configured to measure information about pulse waves propagating through blood in the subject, the subject located in contact with the weight-bearing surface; a second sensor module disposed in the device, the second sensor module configured to measure information about a motion of the subject; and a processing device configured to: receive a first dataset representing time-varying information about at least one pulse wave propagating through blood in the subject, wherein the time-varying information about the at least one pulse wave is measured using the first sensor module; receive a second dataset representing information about a time-varying motion of the subject, wherein the information about the time-varying motion is measured using the second sensor module; identify a first point in the first dataset, the first point representing a

Abstract: A watch comprising a deadfront window; a first OLED display disposed beneath the deadfront window such that the first OLED display can be observed through the deadfront window when the first OLED display is active; a movement for tracking time, the movement having a first portion that resides beneath the deadfront window and a second portion that protrudes through the deadfront window; and time-indicating members disposed above the deadfront window, the time indicating members being secured to the second portion of the movement.

Abstract: A circuit and method for long term electrocardiogram (ECG) monitoring is implemented with the goal of reducing power consumption, battery size, and consequently device size. In one embodiment, the integrated circuit includes an amplifier cell having a plurality of input terminals and an output terminal; a QRS amplifier cell in communication with the output of the amplifier cell; a baseline amplifier cell in communication with the output of the amplifier cell; a comparator cell having a first input terminal in communication with the output terminal of the QRS amplifier cell; and a VDC cell having an input in communication with the output of the baseline amplifier cell and an output in communication with the second input terminal of the comparator cell, wherein the comparator cell generates an output pulse in response to the output signal from the amplifier cell and the output signal from the baseline amplifier cell.

Abstract: The technology described in this document can be embodied in a method that includes obtaining, using a first sensor disposed in a device, a first data set representing time-varying information on at least one pulse pressure wave within vasculature at the wrist of a subject. The method also includes obtaining, using a second sensor disposed in the device, a second data set representing time-varying information about chest vibrations of the subject, and identifying first and second points in the first and second data sets, respectively. The first point represents an arrival time of the pulse pressure wave at the wrist. The second point represents a chest vibration corresponding to an earlier time at which the pulse pressure wave originates at the heart of the subject. Pulse transit time (PTT) is then computed as a difference between the first and second points.

Abstract: The technology described in this document is embodied in a method that includes processing data in a first dataset that represents time-varying information about at least one pulse pressure wave propagating through blood in a subject acquired at a location of the subject. The method also includes providing, based on the data, information about a medication regimen of the subject.

Abstract: The technology described in this document is embodied in a method that includes processing data in a first dataset that represents time-varying information about at least one pulse pressure wave propagating through blood in a subject acquired at a location of the subject. The data is acquired while the subject is in a situation associated with risk indicated by the data.

Abstract: The technology described in this document is embodied in a method that includes processing data in a first dataset that represents time-varying information about at least one pulse pressure wave propagating through blood in a subject acquired at a location of the subject. The method also includes providing information related to the data to a remote device.

Abstract: The technology described in this document is embodied in a method that includes deriving a metric associated with a state of a subject, the state of the subject being one or more members selected from the group consisting of health, sleep, fitness, and stress. Deriving the metric is based on data in a first dataset that represents time-varying information about at least one pulse pressure wave propagating through blood in the subject acquired at a location of the subject.

Abstract: The technology described in this document is embodied in a method that includes obtaining a first data set representing time-varying information on at least one pulse pressure wave at a first body part of a subject. The method also includes obtaining a second data set representing time-varying information about motion of the subject at the first body part of a subject. The method also includes identifying a first point in the first data set, the first point representing an arrival time of the pulse pressure wave at the first body part, and identifying a second point in the second dataset, the second point representing an earlier time at which the pulse pressure wave traverses a second body part of the subject. The method also includes computing a pulse transit time (PTT) as a difference between the first and second points.

Abstract: The technology described in this document is embodied in a method that includes processing data in a dataset that represents time-varying information about at least one pulse pressure wave propagating through blood in a subject acquired at a location of the subject. The method also includes determining whether one or more segments of the dataset were captured from a subject other than an expected subject by analyzing morphological features of the segments.

Abstract: The technology described in this document is embodied in a method that includes processing data in a first dataset that represents time-varying information about at least one pulse pressure wave propagating through blood in a subject acquired at a location of the subject while the subject is sleeping, processing data in a second dataset that represents time-varying information about motion of the subject acquired at the location of the subject while the subject is sleeping, and determining, based on the data, information about a characteristic of the subject's sleep.

Abstract: The technology described in this document is embodied in a method that includes processing data in a first dataset that represents time-varying information about at least one pulse pressure wave propagating through blood in a subject acquired at a location of the subject. The method also includes predicting a medical event of the subject based on the processed data.

Abstract: The technology described in this document is embodied in a method that includes processing data in a first dataset that represents time-varying information about at least one pulse pressure wave propagating through blood in a subject acquired at a location of the subject. The method also includes processing data in a second dataset that represents time-varying information about motion of the subject acquired at the location of the subject. The method also includes detecting arrhythmia of the subject based on the data.

Abstract: The technology described in this document is embodied in a method that includes processing data in a first dataset that represents time-varying information about at least one pulse pressure wave propagating through blood in a subject acquired at a location of the subject. The data in the first and second datasets is acquired while the subject is in a situation that requires at least a predetermined amount of alertness of the subject.