Abstract: A stimulator and a method of controlling the stimulator are provided. The method includes determining a waveform of a stimulus signal for a target, based on biological feedback of the target responding to a first stimulus signal, calculating a bioimpedance of the target based on a voltage waveform measured by applying the stimulus signal with the determined waveform to the target, and determining an operating voltage of the stimulator based on the determined waveform and the calculated bioimpedance.

Abstract: A motion sickness mitigation device includes a textile material having a first surface, a second surface disposed opposite the first surface, and a first raised portion extending from the first surface and configured for contacting a skin of a user. The textile material defines a first pocket and a second pocket therein between the first surface and the second surface, and the second pocket is spaced apart from the first pocket. The device further includes a controller disposed within the first pocket and configured for transmitting an electrical signal. The device also includes a first electrical excitation pad disposed within the second pocket, covered by the first raised portion, and disposed in electrical communication with the controller. The first electrical excitation pad is configured for receiving the electrical signal and electrically stimulating the skin of the user through the textile material to thereby mitigate motion sickness.

Abstract: An integrated circuit includes: a radio-frequency (RF) to direct current (DC) rectifying circuit coupled to one or more antenna on an implantable wirelessly powered device, the rectifying circuit configured to: rectify an input RF signal received at the one or more antennas and from an external controller through electric radiative coupling; and extract DC electric power and configuration data from the input RF signal; a logic control circuit connected to the rectifying circuit and a driving circuit, the logic control circuit configured to: generate a current for the driving circuit solely using the extracted DC electrical power; in accordance with the extracted configuration data, set polarity state information for each electrode; and a driving circuit coupled to one or more electrode, the driving circuit comprising current mirrors and being configured to: steer, to each electrode and via the current mirrors, a stimulating current solely from the generated current.

Abstract: An example of a system may include electrodes on at least one lead configured to be operationally positioned for use in modulating a volume of neural tissue, where the neural tissue has an activation function. The system may further include a neural modulation generator configured to deliver energy using at least some electrodes to generate a modulation field within the volume of neural tissue. The neural modulation generator may be configured to use a programmed modulation parameter set to generate the modulation field. The programmed modulation parameter set having values selected to control energy delivery using the at least some electrodes to achieve an objective function specific to the activation function of the volume of neural tissue to promote uniformity of a response to the modulation field in the volume of neural tissue along a span of the at least one lead.

Abstract: Systems and methods for determining a parameter set and programming a neuromodulation system with the parameter set are disclosed. The system includes a user interface having a display screen to display simplified graphical representations (SGRs) of the lead with at least one virtual electrode (VE) that represents one or more electrodes, and control elements. The SGRs of the lead can provide longitudinal and circumferential representations of the VE, respectively representing longitudinal or circumferential position, size, shape, or spread of the VE. The control elements may include longitudinal and circumferential control elements to enable the user to respectively adjust the longitudinal or circumferential position, size, shape, or spread of the VE. The system may generate the neuromodulation parameter set using the longitudinal and circumferential representations of the VE, and program the neuromodulation system with the neuromodulation parameter set.

Abstract: An electrical stimulation system includes a control module that provides electrical stimulation signals to an electrical stimulation lead coupled to the control module for stimulation of patient tissue. The system also includes a sensor to be disposed on or within the body of the patient and to measure a biosignal; and a processor to communicate with the sensor to receive the biosignal and to generate an adjustment to one or more of the stimulation parameters based on the biosignal. The adjustment can be configured and arranged to steer the electrical stimulation signals to stimulate a region of the patient tissue that is different, at least in part, from a region of the patient tissue stimulated prior to the adjustment. Alternatively or additionally, the biosignal is indicative of a particular patient activity and the adjustment is a pre-determined adjustment selected for the particular patient activity.

Abstract: Restless Leg Syndrome (RLS) or Periodic Limb Movement Disorder (PLMD) can be treated using high frequency (HF) electrostimulation. This can include selecting or receiving a subject presenting with RLS or PLMD. At least one electrostimulation electrode can be located at a location associated with at least one of, or at least one branch of, a sural nerve, a peroneal nerve, or a femoral nerve. HF electrostimulation can be delivered to the subject, which can include delivering subsensory, subthreshold, AC electrostimulation at a frequency that exceeds 500 Hz and is less than 15,000 Hz to the location to help reduce or alleviate the one or more symptoms associated with RLS or PLMD. A charge-balanced controlled-current HF electrostimulation waveform can be used.

Abstract: Electronic devices that detect their position and/or orientation with respect to earth's frame of reference are described. A coupler can removeably maintain the electronic devices in physical proximity of one another. Each electronic device can have a housing and the coupler can be included on the housing and arranged to physically connect the housing of the electronic device to the housing of at least one other electronic device. Alternatively, the coupler can be a packaging that maintains the electronic devices in physical proximity of one another. Each electronic device can be calibrated using the orientation or position information obtained by other electronic devices maintained by the coupler. Further, each electronic device can include a power source that remains inactive until the device is ready for use.

Abstract: A method and system for calibrating a wireless sensor device are disclosed. In a first aspect, the method comprises determining a vertical calibration vector and determining a rotation matrix using the vertical calibration vector to line up native axes of the wireless sensor device with body axes. In a second aspect, a wireless sensor device comprises a processor and a memory device coupled to the processor, wherein the memory device includes an application that, when executed by the processor, causes the processor to determine a vertical calibration vector and to determine a rotation matrix using the vertical calibration vector to line up native axes of the wireless sensor device with body axes.

Abstract: A therapeutic neuromodulation system configured for providing therapy to a patient. The therapeutic neuromodulation system comprises a plurality of electrical terminals configured for being respectively coupled to a plurality of electrodes implanted within tissue, analog output circuitry configured for delivering therapeutic electrical energy between the plurality of electrical terminals in accordance with a set of modulation parameters that includes a defined current value, a voltage regulator configured for supplying an adjustable compliance voltage to the analog output circuitry, and control/processing circuitry configured for automatically performing a compliance voltage calibration process at a compliance voltage adjustment interval by periodically computing an adjusted compliance voltage value as a function of a compliance voltage margin.

Abstract: Portable transdermal electrical stimulation (TES) applicators for modifying a subject's cognitive state by applying stimulation to the subject's skin. One or more electrode may be on the subject's mastoid, and/or on or near the back of the subject's neck. The portable applicators are configured and adapted to be lightweight and may be wearable, and to deliver a high-intensity TES able to evoke or enhance a predetermined cognitive effect to stimulate either the trigeminal, facial and/or cervical plexus. These TES applicators may include a pair of electrodes and a TES control module comprising a processor, a timer and a waveform generator.

Abstract: A method and apparatus for using low levels of electrical stimulation to treat focal dystonia by stimulating the afferent nervous system and/or altering the function of the gamma motor neurons innervating muscles which experience symptomatic spasms.

Abstract: This disclosure describes techniques for generation of sleep quality information based on posture state data. The techniques may include obtaining posture state data sensed by a medical device for a patient, generating sleep quality information based on lying posture state changes indicated by the posture state data, and presenting the sleep quality information to a user via a user interface.

Abstract: A system is configured to provide sensory stimuli to a subject at a first intensity level, determine the effectiveness of the provided sensory stimuli, and incrementally increase the intensity level of the sensory stimuli based on the determined effectiveness. The effectiveness determination and the corresponding intensity increase are repeated one or more times during a given slow wave sleep episode. The system is configured to continue the effectiveness determinations and the corresponding intensity increases during the slow wave sleep episode until the intensity level reaches a maximum level, until an arousal level of the subject breaches an arousal level threshold, and/or until expiration of the period of slow wave sleep.

Abstract: A device and method for monitoring pain of a user (50) are presented. The device (10) comprises a receiving unit (12) for receiving an accelerometer signal (38) from an accelerometer sensor (30) worn by the user (50), wherein the accelerometer signal (38) comprises components of a pulse signal (20) and a respiration signal (22); and a processing unit (14) configured to: derive the pulse signal (20) and the respiration signal (22) from the accelerometer signal (38); adapt the pulse signal (20) based on the respiration signal (22) in order to obtain a corrected pulse signal (40); and derive a pain descriptor based on the corrected pulse signal (40).

Abstract: Systems and methods are provided for delivering neurostimulation therapies to patients for treating chronic heart failure. A neural fulcrum zone is identified and ongoing neurostimulation therapy is delivered within the neural fulcrum zone. The implanted stimulation device includes a physiological sensor for recording the patient's response to the neurostimulation therapy on an ambulatory basis over extended periods of time.

Abstract: An implantable medical device (IMD) is disclosed having measurement circuitry for measuring one or more currents in the IMD, such as the currents drawn from various power supply voltages. Such currents are measured without disrupting normal IMD operation, and can be telemetered from the IMD for review. Switching circuitry in line with the current being measured is temporarily opened for a time period to disconnect the power supply voltage from the circuitry being powered. A voltage across a capacitance in parallel with the circuitry is measured when the switching circuitry is opened and again closed at the end of the time period, with the circuitry drawing power from the charged capacitance during this time period. The average current drawn by the power supply voltage is determined using the difference in the measured voltages, the known capacitance, and the time period between the measurements.

Abstract: An antenna guide assembly including a guide body having a proximal end defining at least one proximal entry, a distal end defining at least one distal port, and at least one guide passage extending between the proximal and distal ends. The at least one guide passage is configured to receive at least a portion of an antenna therethrough via the at least one proximal entry such that a distal portion of the antenna extends through and distally from the at least one distal port for insertion into tissue. A locking assembly disposed at the distal end of the guide body is configured to receive the distal portion of the antenna therethrough. The locking assembly is configured to selectively engage the distal portion of the antenna to prevent translation of the antenna within the at least one guide passage.

Abstract: A neuromodulation system comprises a plurality of electrical terminals configured for being respectively coupled to a plurality of electrodes, a user interface configured for receiving input from a user that selects one of a plurality of different shapes of a modulating signal and/or selects one of a plurality of different electrical pulse parameters of an electrical pulse train, neuromodulation output circuitry configured for outputting an electrical pulse train to the plurality of electrical terminals, and pulse train modulation circuitry configured for modulating the electrical pulse train in accordance with the selected shape of the modulating signal and/or selected electrical pulse parameter of the electrical pulse train.

Abstract: Systems and methods are provided for determining optimized settings for a closed-loop stimulation system based on analyzing a phase response curve measured from electrophysiological activity, such as electrical nerve activity or electrical muscle activity. The slope of the phase response curve is computed and used to determine a phase window during which phasic burst stimulation should be provided to achieve a desired effect on oscillations in the subject. When the slope of the phase response curve is positive, a phasic burst stimulation applied during the phase window will decrease synchrony of the oscillations. When the slope of the phase response curve is negative, a phasic burst stimulation applied during the phase window will increase synchrony of the oscillations.

Abstract: One aspect of the present disclosure relates to a system for treating obstructive sleep apnea in a subject. The system can include a power source and a neuromuscular stimulator in electrical communications with the power source. The neuromuscular stimulator can include a controller and at least one electrode. The controller can be configured to receive certain power and stimulation parameters associated with a therapy signal from the power source. The at least one electrode can be configured to deliver the therapy signal to a target tissue associated with control of a posterior base of the tongue of the subject.

Abstract: A device for directing energy to a target volume of tissue includes a monopole antenna assembly that includes a monopole antenna radiating section having a monopole antenna element surrounded by a dielectric material. The monopole antenna assembly also includes a ground plane disposed at a proximal end of the monopole antenna radiating section, wherein the ground plane is configured to direct energy into the target volume of tissue.

Abstract: An electrosurgical energy channel splitter apparatus includes a channel input a plurality of channel outputs, and a controller. The channel input is configured to receive electrosurgical energy from an electrosurgical energy source. Each channel output is configured to couple to a respective electrosurgical device. The controller is coupled to the channel input and the plurality of channel outputs. The controller is configured to selectively direct the electrosurgical energy from the channel input to one of the plurality of channel outputs.

Abstract: The present disclosure provides systems and methods for correlating measurement in neurostimulation systems. A neurostimulation system includes a first sensor configured to acquire movement measurements for a subject, a second sensor configured to acquire neural measurements for the subject, and a computing device communicatively coupled to the first and second sensors. The computing device is configured to receive a movement signal from the first sensor, and receive a neural signal from the second sensor, wherein one of the movement signal and the neural signal is a trigger signal and the other of the movement signal and the neural signal is a signal of interest. The computing device is further configured to detect at least one trigger event in the trigger signal, and use the signal of interest based on the at least one trigger event.

Abstract: An apparatus for controlling the stimulation of neural tissue which includes a neural stimulator, an input device for providing input to the neural stimulator for neural stimulation, at least one electrode electrically connected to and driven by the neural stimulator and suitable to stimulate neural tissue, a device capable of determining a charge per phase by calculating a discrete integral of the wave form of the input for the at least one electrode, a calculating device for comparing the charge per phase to a predetermined maximum and determining a reduced stimulation for the at least one electrode by the amount necessary not to exceed the predetermined maximum for the at least one electrode, and a current pulse generator for stimulating the neural tissue according to the reduced stimulation level.

Abstract: Systems and methods are provided for delivering neurostimulation therapies to patients for treating chronic heart failure. A computer-implemented control system is operated to automatically identify a neural fulcrum zone based on a monitored patient physiological response. Ongoing neurostimulation therapy is delivered within the neural fulcrum zone.

Abstract: A system for assisted coughing includes a first sensor for measuring a parameter which can indicate a closed glottis and producing a first signal, a processor for receiving the first signal, determining a state indicating the closed glottis and generating an instruction for a Functional Electric Stimulation (FES) controller based, at least in part, on the determining, and a FES controller for generating an electric stimulation signal.

Abstract: A system embodiment comprises a neural stimulator having a housing with an electrode on the housing and having a neural stimulation lead with an electrode on the neural stimulation lead. The neural stimulator is configured to deliver a neural stimulation therapy through the neural stimulation lead and remotely sense a heart rate using the electrode on the neural stimulation lead and the electrode on the housing of the neural stimulator.

Abstract: Devices for controlling spinal cord modulation for inhibiting pain, and associated systems and methods, including controllers for modulation program recommendation are disclosed. A particular embodiment includes receiving, from multiple computing devices, ratings for modulation programs executed by implantable medical devices for a plurality of patients, ranking the modulation programs based on the received ratings and based on at least one characteristic of the patients and the symptoms described by the patients, receiving a recommendation request for a modulation program for a particular patient; and transmitting one or more of the highest ranking modulation programs in response to the request for a modulation program for the particular patient.

Abstract: A system for stimulating the release of satiety hormone in a subject comprises a stimulus device which is implantable in the subject and adapted to apply an electrical stimulus to a tissue of a gastrointestinal system of said subject, and a detection device which is implantable in the subject and adapted to continuously monitoring at least one of a mechanical characteristic and an electrical characteristic of the subject to detect an ingestion of food by said subject, wherein the detection device cooperates with the stimulus device such that the stimulus device applies said electrical stimulus in response to a detected ingestion of food.

Abstract: A positionally sensitive spinal cord stimulation apparatus and method using near-infrared (NIR) reflectometry are provided for automatic adjustments of spinal cord stimulation. The system comprises an electrode assembly with an integrated optical fiber sensor for sensing spinal cord position. The integrated optical fiber sensor, comprising a pair of optical elements for emitting light from an IR emitter and for collecting reflected light into a photodetector, determines a set of measured photocurrents. As the spinal cord changes position, the angles of incidence for light from the IR emitter and the measured optical intensities change. Electrode pulse characteristics are adjusted in real time, based on the set of measured optical intensities, to minimize changes in stimulation perceived by the patient during motion. The system includes automatic calibration of the optical fiber sensor when the patient is at rest, and a patient orientation detection.

Abstract: A medical device and associated method record signals from each real axis of a multi-axis sensor. An optimal axis for monitoring a physiological signal of the patient is identified from the real axes of the multi-axis sensor and multiple virtual axes. Coordinates defining the optimal axis are stored as respective weighting factors of the signals from each real axis of the multi-axis sensor. A metric of the physiological signal is determined using the multi-axis sensor signals and the weighting factors.

Abstract: Methods and circuitry for determining an implanted-neurostimulator patient's position, and adjusting a situation program delivered by the neurostimulator based on the determined position, is disclosed. Impedance measurements of the patient's tissue are taken at the neurostimulator's electrodes, which measurements can comprise complex impedance measurements (magnitude and phase) taken at different frequencies. Such impedance measurements, which can be taken interleaved with stimulation therapy, are used to determine an “impedance fingerprint.” This fingerprint can be compared to other known fingerprints stored in the IPG, which known fingerprints are associated with particular stimulation programs. When a measured fingerprint matches one stored in the IPG, the stimulation program associated with the stored fingerprint is automatically used for patient therapy.

Abstract: A method and apparatus for using low levels of electrical stimulation to treat focal dystonia by stimulating the afferent nervous system and/or altering the function of the gamma motor neurons innervating muscles which experience symptomatic spasms.

Abstract: A method, including obtaining data indicative of an ability of a recipient of a hearing prosthesis to discriminate between tokens of respective token pairs of a plurality of token pairs in respective evoked hearing percepts induced by the hearing prosthesis and adjusting one or more but less than all frequency channels of a plurality of frequency channels of the hearing prosthesis based on the obtained data.

Abstract: An example of a system may include an electrode arrangement, a neural modulation generator configured to use electrodes in the electrode arrangement to generate a modulation field, a communication module configured to receive commands, a memory configured to store modulation field parameter data, and a controller configured to control the neural modulation generator to generate the modulation field. The controller may be configured to implement a trolling routine to troll the modulation field through neural tissue positions, and implement a marking routine multiple times as the modulation field is trolled through the neural tissue positions to identify when the modulation field provides patient-perceived modulation.

Abstract: A biological information measurement apparatus includes a phase/frequency comparison unit that outputs a deviation signal based on a phase difference between a biological signal and an oscillation signal; a loop filter; and a voltage controlled oscillation unit that generates the oscillation signal in accordance with the deviation signal that has passed through the loop filter. The apparatus further includes a CPU that estimates a SN ratio of the biological signal and analyzes a phase difference/frequency difference between the biological signal and the oscillation signal. A variable low pass filter is provided that selectively blocks a signal of a predetermined frequency band contained in the deviation signal that has passed through the loop filter and the CPU changes a cutoff frequency of the variable low pass filter based on the SN ratio and the phase difference/frequency difference.

Abstract: The present disclosure relates to methods and apparatus for the treatment of spasmodic dysphonia, such as methods of treating spasmodic dysphonia that include providing a system that includes a stimulating electrode operably connected with a processor configured to set one or more stimulation parameters for an electrical impulse deliverable by said electrode, placing the electrode in electrical contact with the superior laryngeal nerve, using the processor to set the stimulation parameters such that the electrical impulse causes a level of stimulation that does not exceed the excitability threshold of one or more alpha motor neurons located within the thyroarytenoid muscle; and delivering the electrical impulse to the superior laryngeal nerve.

Abstract: A therapeutic neurostimulation system configured for providing therapy to a patient. The neurostimulation system comprises a neurostimulation lead having an array of electrodes arranged along a longitudinal axis configured for being implanted along a spinal cord of a patient, a neurostimulation device configured for delivering electrical stimulation energy to active ones of the electrode array, and control/processing circuitry for instructing the neurostimulation device to configure an active electrode as a cathode, and two active electrodes longitudinally flanking and laterally offset from the cathode as anodes, selecting a ratio of stimulation amplitude values for the two anodes based on a known longitudinal location of the implanted neurostimulation lead relative to the spinal cord, and instructing the neurostimulation device to distribute the electrical stimulation energy between the two anodes in accordance with the selected stimulation amplitude value ratio.

Abstract: A system includes a therapy control circuit, a therapy output circuit; and a physiologic interval sensing circuit configured to receive information about subject physiologic intervals. The therapy circuit is configured to determine a change in therapy that is provided by the therapy output circuit, determine that the change in therapy includes a change to a maximum interval of cardiac electrostimulation provided according to the therapy, detecting a change in a ventricular filling characteristic of the subject in response to the change in maximum interval of cardiac electrostimulation, determine an indication of a physiologic response of the subject to the therapy change using information about the change in the ventricular filling characteristic, and update the subject therapy provided by the therapy output circuit when the determined indication of the physiologic response to the therapy change indicates an increased likelihood of worsening health status of the subject.

Abstract: Apparatus and method for treating an arrhythmia in a patient using an electrotherapy device such as a subcutaneous pacing device. The device applies a series of electrotherapy pulses in response to the presence of the arrhythmia. Various provisions are disclosed for mitigating pain or discomfort as a result of the electrotherapy pulses.

Abstract: An embodiment relates to a method for delivering a vagal stimulation therapy to a vagus nerve, including delivering a neural stimulation signal to non-selectively stimulate both afferent axons and efferent axons in the vagus nerve according to a predetermined schedule for the vagal stimulation therapy, and selecting a value for at least one parameter for the predetermined schedule for the vagal stimulation therapy to control the neural stimulation therapy to avoid physiological habituation to the vagal stimulation therapy. The parameter(s) include at least one parameter selected from the group of parameters consisting of a predetermined therapy duration parameter for a predetermined therapy period, and a predetermined intermittent neural stimulation parameter associated with on/off timing for the intermittent neural stimulation parameter.

Abstract: A therapeutic neuromodulation system configured for providing therapy to a patient. The therapeutic neuromodulation system comprises a plurality of electrical terminals configured for being respectively coupled to a plurality of electrodes implanted within tissue, analog output circuitry configured for delivering therapeutic electrical energy between the plurality of electrical terminals in accordance with a set of modulation parameters that includes a defined current value, a voltage regulator configured for supplying an adjustable compliance voltage to the analog output circuitry, and control/processing circuitry configured for automatically performing a compliance voltage calibration process at a compliance voltage adjustment interval by periodically computing an adjusted compliance voltage value as a function of a compliance voltage margin.

Abstract: A tissue stimulation system and computer software and method of monitoring a neurostimulation lead having a plurality of electrodes implanted within a patient (e.g., adjacent the spinal cord) is provided. Neurostimulation lead models are provided, each of which includes estimated electrical parameter data (e.g., electrical field potential data) corresponding to a predetermined position of the neurostimulation lead. Electrical energy is transmitted to or from the electrodes, and electrical parameter data (e.g., electrical field potential data) is measured in response to the transmitted electrical energy. The measured electrical parameter data is compared with the estimated electrical parameter data of each of the neurostimulation lead models, and a position of the neurostimulation lead is determined based on the comparison.

Abstract: Sensors are applied to the heart and sensor data is supplied to a rules engine. The rules engine applies rules that reflect a CRM pharmaceutical regime of the patient to the sensor data to determine whether an electrical waveform should be applied to the heart. When electrical stimulation is warranted, the drug “awareness” rules are used by the rules engine to instruct a multi-phase cardiac stimulus generator to generate an electrical waveform that improves the performance of the drugs administered to the patient, allow the patient to be administered a lower dose of a particular drug, and/or reduce or eliminate side effects from the drugs.

Abstract: System and methods for programming and delivering electrical stimulation to treat hypertension are described. In various embodiments, an ambulatory stimulator system, such as an implantable medical device, can detect a respiration-mediated heart rate variation (RM-HRV), monitor the efficacy of hypertension therapy and adjust the stimulation parameters using the detected RM-HRV to achieve desired therapy outcome. In some embodiments, the system can be configured to synchronize the detected heart rates to one or more respiration cycles or respiration phases within the respiration cycles, and determine the RM-HRV using the heart rates synchronized with the respiration cycles or the respiration phases. The RM-HRV may be presented to the system operator to monitor the efficacy of the AHT therapy. The ambulatory stimulator system can adjust the stimulation parameters using at least the RM-HRV.

Abstract: Systems and methods are provided for delivering neurostimulation therapies to patients for treating chronic heart failure. A neural fulcrum zone is identified and ongoing neurostimulation therapy is delivered within the neural fulcrum zone. The implanted stimulation device includes a physiological sensor for recording the patient's response to the neurostimulation therapy on an ambulatory basis over extended periods of time.

Abstract: A device includes a pulse generator coupled to a neurostimulation lead placed around the nerve and a set of electrodes individually connected to the generator by a splitter circuit controlled to preferentially stimulate certain regions of the nerve relative to other regions. The device performing an iterative search of an optimal configuration operating by selection of a plurality of different stimulation configurations, storing of a cardiac physiological parameter measured for each selected stimulation configuration, and designation as optimal stimulation configuration of the one of said selected different stimulation configurations, depending on at least the stored values of the physiological parameter measured for different electrode configurations.

Abstract: A microwave ablation system includes an energy source adapted to generate microwave energy and a power splitting device having an input adapted to connect to the energy source and a plurality of outputs. The plurality of outputs are configured to be coupled to a corresponding plurality of energy delivery devices. The power splitting device is configured to selectively divide energy provided from the energy source between the plurality of energy devices.

Abstract: A method and apparatus for using low levels of electrical stimulation to treat focal dystonia by stimulating the afferent nervous system and/or altering the function of the gamma motor neurons innervating muscles which experience symptomatic spasms.