An automated method of controlling neural stimulation. A neural stimulus is applied to a neural pathway in order to give rise to an evoked action potential on the neural pathway, and the stimulus is defined by at least one stimulus parameter. A neural compound action potential response evoked by the stimulus is measured. From the measured evoked response a feedback variable such as observed ECAP voltage (V) is derived. A feedback loop is completed by using the feedback variable to control the at least one stimulus parameter value for a future stimulus. The method adaptively compensates for changes in a gain of the feedback loop caused by electrode movement relative to the neural pathway. A compensating transfer function is applied to the feedback variable, the compensating transfer function being configured to compensate for both (i) a distance-dependent transfer function of stimulation, and (ii) a distance dependent transfer function of measurement which is distinct from (i).

A system may include one implantable pulse generator and at least one implantable lead. The pulse generator may include a processor, a driving system for driving electrodes, a communication circuit, and a housing configured to be subcutaneously implanted. The lead may be configured to extend from the pulse generator to at least one neural target on a left side of a head and a neural target on a right side of the head. The lead may include at least two electrode sets, each including at least two electrodes. The lead be configured to be used to subcutaneously place the at least two electrode sets near the at least two neural targets, respectively, and electrically connect the pulse generator to each of the at least two electrodes sets to enable the driving system to drive the at least two electrode sets to stimulate the at least two neural targets.

A method and device is described, which provides electrical stimulation to the brain of a person, where the device comprises an external portion and at least one implantable portion. The external portion provides the energy source for stimulation to the implantable portions. The implantable portions provide at least two conductive paths through the skull and use the skull's high impedance to generate a current loop with the focus of stimulation lying in the current path.

A neural stimulus comprises at least three stimulus components, each comprising at least one of a temporal stimulus phase and a spatial stimulus pole. A first stimulus component delivers a first charge which is unequal to a third charge delivered by a third stimulus component, and the first charge and third charge are selected so as to give rise to reduced artefact at recording electrodes. In turn this may be exploited to independently control a correlation delay of a vector detector and an artefact vector to be non-parallel or orthogonal.

A method is described, which provides electrical stimulation to a person, where the current flows from a subcranial electrode, through a target brain region, through a separate conductive path, and back to a subcutaneous electrode, and where the parameters of the electric current pulses are set to influence the resonant properties of the brain.

An implantable stimulator is provided having a conformable foil-like substrate, having a longitudinal axis extending from a pulse generator to a distal end of the substrate. The substrate comprising one or more adjacent polymeric substrate layers and an electrode array. The electrode array having a first and second electrode where one or more electrical interconnections are comprised in the substrate. The conformable foil-like substrate has a maximum thickness of 0.5 millimeter or less, proximate the electrodes. By providing a more easily patternable multilayer substrate, more complicated electrode array configurations may be supported, allowing a higher degree of flexibility to address transverse and/or longitudinal misalignment. By providing a relatively thin implantable electrode array user comfort may be increased through application of energy to tissue by the implantable stimulator.

In general, implantation of neurostimulation systems or device includes subcutaneous or percutaneous placement of at least the electrodes. Preferred are minimally invasive implantation procedures, systems and devices that can reliably operate for extended periods, and systems and devices providing a high degree of comfort for the subject. The implantation specialist may need to address adequate placement of the electrodes with respect to the nerve tissue to be stimulated, and to choose between one or more convenient locations for the elements of the system or device.

Methods are provided comprising forming a first 1250 and second 1260 incision on opposite sides of a target location, and introducing a first introducer sheath 3050a under the skin with a maximum internal transverse cross-section less than the further maximum transverse cross-section 710 of an implantable stimulator. Such a method is advantageous if the maximum transverse cross-section 710 of the further portion is at least 1.2 times greater than the maximum transverse cross-section 730 of the first portion—the dimensions of the implantation tools may be reduced.

A further method is provided wherein the first portion 630 with at least two electrodes 200, 400 is introduced in the skin layers between the nerve tissue 2003 to be stimulated and above or in the aponeurosis layer 2009.

By being implanted deeper and/or more accurately, comfort and/or reliability for the subject may be improved. In addition, the chance that the stimulator is implanted under the nerve tissue is greatly increased.

A method includes: transmitting a first set of radio-frequency (RF) pulses to an implantable wireless stimulator device such that electric currents are created from the first set of RF pulses and flown through a calibrated internal load on the implantable wireless stimulator device; in response to the electric currents flown through a calibrated internal load, recording a first set of RF reflection measurements; transmitting a second set of radio-frequency (RF) pulses to the implantable wireless stimulator device such that stimulation currents are created from the second set of RF pulses and flown through an electrode of the implantable wireless stimulator device to tissue surrounding the electrode; in response to the stimulation currents flown through the electrode to the surrounding tissue, recording a second set of RF reflection measurements; and characterizing an electrode-tissue impedance by comparing the second set of RF reflection measurements with the first set of RF reflections measurements.

A neural stimulus comprises at least three stimulus components, each comprising at least one of a temporal stimulus phase and a spatial stimulus pole. A first stimulus component delivers a first charge which is unequal to a third charge delivered by a third stimulus component, and the first charge and third charge are selected so as to give rise to reduced artefact at recording electrodes. In turn this may be exploited to independently control a correlation delay of a vector detector and an artefact vector to be non-parallel or orthogonal.

In certain variations, systems and/or methods for electromagnetic induction therapy are provided. One or more ergonomic or body contoured applicators may be included. The applicators include one or more conductive coils configured to generate an electromagnetic or magnetic field focused on a target nerve, muscle or other body tissues positioned in proximity to the coil. One or more sensors may be utilized to detect stimulation and to provide feedback about the efficacy of the applied electromagnetic induction therapy. A controller may be adjustable to vary a current through a coil to adjust the magnetic field focused upon the target nerve, muscle or other body tissues based on the feedback provide by a sensor or by a patient. In certain systems or methods, pulsed magnetic fields may be intermittently applied to a target nerve, muscle or tissue without causing habituation.