Abstract: The invention relates to a method for characterizing a target polynucleic acid by providing a surface containing a channel of a dimension sufficient to allow sequential monomer-by-monomer passage of a single-stranded polynucleic acid, but not of a double-stranded polynucleic acid; providing a source of hybridized target polynucleic acid at the surface; inducing passage of the target polynucleic acid through the channel, whereby the target polynucleic acid undergoes base pair separation (melts) prior to its passage; and making one or more measurements over time as the target polynucleic acid moves relative to the channel yielding data suitable to determine a monomer-dependent characteristic of the target polynucleic acid.

Abstract: Methods of delivering optical stimulation to a target tissue from an optical stimulation device are provided. One method comprises sensing a temperature at the optical stimulation device or proximate to the optical stimulation device, and adjusting the delivery of light to the target tissue based on the sensed temperature. Another method comprises delivering the light to the target tissue with an optical light guide and sensing bioelectric signals with a sense electrode, wherein the optical light guide and the sense electrode each comprise a material that produces substantially no induced current in an electromagnetic field. Another method comprises delivering light from a light source of an optical stimulation device to a window of the optical stimulation device, delivering the light from the window to an optical light guide optically connected to the window, and delivering the light to a target tissue via the optical light guide.

Abstract: This disclosure describes a chopper mixer telemetry circuit for use in a wireless receiver. The receiver may be located in an implantable medical device (IMD) or external programmer. The chopper mixer telemetry circuit may include a mixer amplifier that operates as a synchronous demodulator to provide selective extraction of wireless signals received from a transmitter while suppressing out-of-band noise that can undermine the reliability of the telemetry link between an IMD or programmer and another device. The mixer amplifier may utilize parallel signal paths to convert the received telemetry signal into an in-phase (I) signal component and a quadrature (Q) signal component and recombine the I and Q signal components to reconstruct the total signal independently of the phase mismatch between the transmitter and receiver. Each signal path may include a chopper-stabilized mixer amplifier that amplifies telemetry signals within a desired band while suppressing out-of-band noise.

Abstract: This disclosure describes techniques for controlling spectral aggressors in a sensing device that uses a low power sleep mode to manage the power consumed by the device. In some examples, the techniques for controlling spectral aggressors may include configuring one or more of an algorithm processing rate for a processor, a buffering rate for the processor, a sampling rate for an analog-to-digital converter, an execution unit processing rate for the processor, and an algorithm subdivision factor for the processor such that spectral interference caused by a sleep cycle rate of the processor occurs outside of one or more target frequency bands of a sampled signal. The techniques of this disclosure may be used to reduce noise in a sensing system that uses a low power sleep mode to manage the power consumed by the device.

Abstract: This disclosure describes techniques for controlling spectral aggressors in a sensing device that uses a chopper amplifier to amplify an input signal prior to sampling the signal. In some examples, the techniques for controlling spectral aggressors may include generating a chopper-stabilized amplified version of an input signal based on a chopper frequency, sampling the chopper-stabilized amplified version of the input signal at a sampling rate to generate a sampled signal, and analyzing a target frequency band of the sampled signal. The chopper frequency and the sampling rate may cause spectral interference that is generated due to the chopper frequency to occur in the sampled signal at one or more frequencies that are outside of the target frequency band of the sampled signal. The techniques for controlling spectral aggressors may reduce the noise caused by the chopper frequency in the resulting sampled signal, thereby improving the quality of the signal.

Abstract: This disclosure describes a chopper mixer telemetry circuit for use in a wireless receiver. The receiver may be located in an implantable medical device (IMD) or external programmer. The chopper mixer telemetry circuit may include a mixer amplifier that operates as a synchronous demodulator to provide selective extraction of wireless signals received from a transmitter while suppressing out-of-band noise that can undermine the reliability of the telemetry link between an IMD or programmer and another device. The mixer amplifier may utilize parallel signal paths to convert the received telemetry signal into an in-phase (I) signal component and a quadrature (Q) signal component and recombine the I and Q signal components to reconstruct the total signal independently of the phase mismatch between the transmitter and receiver. Each signal path may include a chopper-stabilized mixer amplifier that amplifies telemetry signals within a desired band while suppressing out-of-band noise.

Abstract: Various embodiments concern delivering electrical stimulation to the brain at a plurality of different levels of a stimulation parameter and sensing a bioelectrical response of the brain to delivery of the electrical stimulation for each of the plurality of different levels of the stimulation parameter. A suppression window of the stimulation parameter can be identified as having a suppression threshold as a lower boundary and an after-discharge threshold as an upper boundary based on the sensed bioelectrical responses. A therapy level of the stimulation parameter can be set for therapy delivery based on the suppression window. The therapy level of the stimulation parameter may be set closer to the suppression threshold than the after-discharge threshold within the suppression window. Data for hippocampal stimulation demonstrating a suppression window is presented.

Abstract: An external medical device generates a drive signal inductively coupled to an implantable coil from an external coil. A regulator module coupled to the implantable coil generates an output signal in response to the inductively coupled signal and a feedback signal correlated to an amplitude of the inductively coupled signal. A signal generator receives the output signal for generating a therapeutic electrical stimulation signal. The control module adjusts the drive signal in response to the feedback signal to control the electrical stimulation signal.

Abstract: Bioelectrical signals may be sensed within a brain of a patient with a plurality of sense electrode combinations. A stimulation electrode combination for delivering stimulation to the patient to manage a patient condition may be selected based on the frequency band characteristics of the sensed signals. In some examples, a stimulation electrode combination associated with the sense electrode combination that sensed a bioelectrical brain signal having a relatively highest relative beta band power level may be selected to deliver stimulation therapy to the patient. Other frequency bands characteristics may also be used to select the stimulation electrode combination.

Abstract: Bioelectrical signals may be sensed within a brain of a patient with a plurality of sense electrode combinations. A stimulation electrode combination for delivering stimulation to the patient to manage a patient condition may be selected based on the frequency band characteristics of the sensed signals. In some examples, a stimulation electrode combination associated with the sense electrode combination that sensed a bioelectrical brain signal having a relatively highest relative beta band power level may be selected to deliver stimulation therapy to the patient. Other frequency bands characteristics may also be used to select the stimulation electrode combination.

Abstract: Various embodiments concern delivering electrical stimulation to the brain at a plurality of different levels of a stimulation parameter and sensing a bioelectrical response of the brain to delivery of the electrical stimulation for each of the plurality of different levels of the stimulation parameter. A suppression window of the stimulation parameter can be identified as having a suppression threshold as a lower boundary and an after-discharge threshold as an upper boundary based on the sensed bioelectrical responses. A therapy level of the stimulation parameter can be set for therapy delivery based on the suppression window. The therapy level of the stimulation parameter may be set closer to the suppression threshold than the after-discharge threshold within the suppression window. Data for hippocampal stimulation demonstrating a suppression window is presented.

Abstract: Bioelectrical signals may be sensed within a brain of a patient with a plurality of sense electrode combinations. A stimulation electrode combination for delivering stimulation to the patient to manage a patient condition may be selected based on the frequency band characteristics of the sensed signals. In some examples, a stimulation electrode combination associated with the sense electrode combination that sensed a bioelectrical brain signal having a relatively highest relative beta band power level may be selected to deliver stimulation therapy to the patient. Other frequency bands characteristics may also be used to select the stimulation electrode combination.

Abstract: The invention relates to a method for characterizing a target polynucleic acid by providing a surface containing a channel of a dimension sufficient to allow sequential monomer-by-monomer passage of a single-stranded polynucleic acid, but not of a double-stranded polynucleic acid; providing a source of hybridized target polynucleic acid at the surface; inducing passage of the target polynucleic acid through the channel, whereby the target polynucleic acid undergoes base pair separation (melts) prior to its passage; and making one or more measurements over time as the target polynucleic acid moves relative to the channel yielding data suitable to determine a monomer-dependent characteristic of the target polynucleic acid.

Abstract: Seizure prediction systems and methods include measuring impedance and a potential within a brain of a patient to determine whether the brain is in a state indicative of a possibility of seizure. In some embodiments, at least one of the measured impedance or the measured potential may be used as a primary indication of the brain state indicative of a possibility of seizure. In one embodiment, if one of the measured impedance or the measured potential indicates a seizure, the other measurement (impedance or potential) may be used to validate whether the brain is in the state indicative of the possibility of seizure.

Abstract: Aspects of this disclosure relate to coupling and decoupling a power source of a device with circuitry within the device. For example, in aspects of this disclosure, when a short develops within the device, a switch circuit may decouple the power source from the some of the circuitry within the device. Decoupling the power source when a short develops may extent the operational time of the power source, and may reduce thermal excursion.

Abstract: This disclosure describes techniques for generating stimulation current pulses that have differing pulse shapes in a medical device. A circuit architecture is described that is configured to charge a capacitor to an initial amount of charge, modulate the amount of charge stored in the capacitor based on a control signal, and generate a stimulation current pulse that has an amplitude based on the amount charge stored in the capacitor. The circuit architecture may be configured to generate complex pulse shapes, such as, e.g., steps, ramps, bursts, and combinations thereof.

Abstract: The invention relates to a method for characterizing a target polynucleic acid by providing a surface containing a channel of a dimension sufficient to allow sequential monomer-by-monomer passage of a single-stranded polynucleic acid, but not of a double-stranded polynucleic acid; providing a source of hybridized target polynucleic acid at the surface; inducing passage of the target polynucleic acid through the channel, whereby the target polynucleic acid undergoes base pair separation (melts) prior to its passage; and making one or more measurements over time as the target polynucleic acid moves relative to the channel yielding data suitable to determine a monomer-dependent characteristic of the target polynucleic acid.

Abstract: A movement state of a patient is detected based on brain signals, such as an electroencephalogram (EEG) signal. In some examples, a brain signal within a dorsal-lateral prefrontal cortex of a brain of the patient indicative of prospective movement of the patient may be sensed in order to detect the movement state. The movement state may include the brain state that indicates the patient is intending on initiating movement, initiating movement, attempting to initiate movement or is actually moving. In some examples, upon detecting the movement state, a movement disorder therapy is delivered to the patient. In some examples, the therapy delivery is deactivated upon detecting the patient is no longer in a movement state or that the patient has successfully initiated movement. In addition, in some examples, the movement state detected based on the brain signals may be confirmed based on a signal from a motion sensor.

Abstract: A system and method for determining complex intercardiac impedance to detect various cardiac functions are disclosed involving a signal generator means for providing an adjustable direct current signal, a modulator for modulating the adjustable direct current signal to produce a modulated signal, at least one electrode for propagating the modulated signal across a myocardium, at least one sensor for detecting an outputted modulated signal from the myocardium, and at least one circuit to reduce the influence of process noise (aggressors) in the outputted modulated signal. The at least one circuit comprises an amplifier, a demodulator, and an integrator. The amplitude and phase of the final outputted modulated signal indicate the complex impedance of the myocardium. Changes in the complex impedance patterns of the myocardium provide indication of reduced oxygen and blood flow to the myocardium.

Abstract: Bioelectrical signals may be sensed within a brain of a patient with a plurality of sense electrode combinations. A stimulation electrode combination for delivering stimulation to the patient to manage a patient condition may be selected based on the frequency band characteristics of the sensed signals. In some examples, a stimulation electrode combination associated with the sense electrode combination that sensed a bioelectrical brain signal having a relatively highest relative beta band power level may be selected to deliver stimulation therapy to the patient. Other frequency bands characteristics may also be used to select the stimulation electrode combination.