Abstract: An electrochemical impedance spectrogram (EIS) measurement system includes a working electrode configured to provide a triangular excitation signal to a subject, and a counter electrode configured to measure an electrical parameter in response to the triangular excitation signal. Based on the triangular excitation signal and the measured electrical parameter, an EIS of the subject is obtained. A method for measuring an EIS of a subject includes causing a triangular excitation signal to be applied to a subject and obtaining electrical parameter measurements in response to the triangular excitation signal. The EIS of the subject is obtained based on the triangular excitation signal and the electrical parameter measurements.

Abstract: A system and method for modulating optogenetic vagus neurons in a noninvasive and transcutaneous manner is disclosed. The system and method comprises a two-dimensional array of organic light emitting diodes (OLEDs), a voltage-generating unit, a control unit, and a feedback loop. The array is placed on a subject's outer ear. Because the array is flexible, it can be closely placed on the skin of the outer ear. The array can deliver optical therapy and monitor heart rate variability (HRV) of the subject simultaneously, and the pixels of the array can be individually addressed. The voltage-generating unit generates pulsed voltage to the OLEDs. The control unit is connected to the array and controls the array and therapeutic patterns. The feedback loop uses the HRV to identify the therapeutic patterns.

Abstract: Rapid assessment of microcirculation in tissue to realize closed-loop systems is provided. Microcirculatory assessment systems according to embodiments described herein allow a user to assess changes in local blood flow in microvasculature in real-time using conventional electrical techniques. Some embodiments provide a closed-loop system that allows calibrated doses of electrical stimulation to be delivered in a deep brain stimulation (DBS) system depending on blood flow changes (in specific regions of the brain) being fed back to a controller. The approach described here is readily translatable with very minimal changes to existing hardware. Such closed-loop systems will improve the accuracy of electrode placement in DBS surgery and potentially reduce surgery time, optimize the delivery of electrical stimulation, increase battery life of implantable DBS systems, reduce post-surgical visits to medical practitioners and improve the quality of life of patients.

Abstract: A microelectromechanical device and method for neuroprosthetics comprises microactuators and microelectrodes. The microelectrodes are to be positioned in a nerve bundle and bonded with the microactuators through an interconnect. The position of each of the microactuators can be individually tuned through control signals so that the microelectrodes are implanted at desired positions in the nerve bundle. The control signals are transmitted to the microactuators and generated with a open-loop or closed-loop control scheme that uses signals acquired by the microelectrodes from the nerve bundle as feedback.

Abstract: A soft conductive composition can include: a crosslinked silicone composition; and single-walled or multi-walled carbon nanotubes in the silicone composition. A neural probe or other implant can include the soft conducive composition on a least a portion of the implant body. A method of making an implant can include: selecting PDMS precursors; cross-linking the PDMS precursor to obtain an elastic modulus of about 3-9 kPa or +/? 1%, 5%, 10%, 20%, or 50%; selecting the carbon nanotubes; introducing the carbon nanotubes into the crosslinked PDMS to form a soft conductive composite composition; and coating the soft conductive composite composition onto at least a portion of an implant. A method of measuring properties at a neural interface can include: providing a neural probe having a soft conductive composition; implanting the neural probe having the soft conductive composition at a neural interface; and measuring a property with the neural probe.

Abstract: Systems and methods for improved control and performance of cochlear implants are disclosed. In an embodiment, the audio environment is sampled, and a neural network determines suggested filter setting for the cochlear implant. The process is repeated such that, as the user moves through various audio environments having differing noise levels, satisfactory performance of the cochlear implant is maintained for the user.

Abstract: A soft conductive composition can include: a crosslinked silicone composition; and single-walled or multi-walled carbon nanotubes in the silicone composition. A neural probe or other implant can include the soft conducive composition on a least a portion of the implant body. A method of making an implant can include: selecting PDMS precursors; cross-linking the PDMS precursor to obtain an elastic modulus of about 3-9 kPa or +/?1%, 5%, 10%, 20%, or 50%; selecting the carbon nanotubes; introducing the carbon nanotubes into the crosslinked PDMS to form a soft conductive composite composition; and coating the soft conductive composite composition onto at least a portion of an implant. A method of measuring properties at a neural interface can include: providing a neural probe having a soft conductive composition; implanting the neural probe having the soft conductive composition at a neural interface; and measuring a property with the neural probe.

Abstract: A soft conductive composite composition can include a soft matrix containing a conductive member that is associated with a bioactive component. The soft matrix can be formed from a silicone composition. The conductive member can be carbon nanotubes in the silicone composition. The carbon nanotubes can have at least two walls and be conductive. Also, the carbon nanotubes can be a mixture of functionalized carbon nanotubes and non-functionalized carbon nanotubes, which mixture can have a ratio of 1:2 to 1:20 w/w of functionalized to non-functionalized carbon nanotubes per gram of the silicone composition. The bioactive component (e.g., enzyme) can be associated with at least a first portion of the carbon nanotubes. A second portion of the carbon nanotubes can be devoid of the bioactive component.

Abstract: A soft conductive composition can include: a crosslinked silicone composition; and single-walled or multi-walled carbon nanotubes in the silicone composition. A neural probe or other implant can include the soft conducive composition on a least a portion of the implant body. A method of making an implant can include: selecting PDMS precursors; cross-linking the PDMS precursor to obtain an elastic modulus of about 3-9 kPa or +/?1%, 5%, 10%, 20%, or 50%; selecting the carbon nanotubes; introducing the carbon nanotubes into the crosslinked PDMS to form a soft conductive composite composition; and coating the soft conductive composite composition onto at least a portion of an implant. A method of measuring properties at a neural interface can include: providing a neural probe having a soft conductive composition; implanting the neural probe having the soft conductive composition at a neural interface; and measuring a property with the neural probe.

Abstract: A micro-scale implantable bioelectronic medical device system that allows multichannel neurostimulation of peripheral nerve bundles so to affect a more localized and specific control over neuromodulation of body tissues and organs. Such systems can be used in medical therapeutic applications for the treatment of a wide variety of disorders of the human body and may be applied in the growing field of medical neuromodulation. Systems and processes may also provide a way of interfacing to nerve and muscle for purposes of the control of advanced robotic prosthetics as well as man-machine interfaces. Apparatus, systems and processes may be adapted in various embodiments to the stimulation of brain and other bioelectrically excitable tissues in the human body as well.

Abstract: Rapid assessment of microcirculation in tissue to realize closed-loop systems is provided. Microcirculatory assessment systems according to embodiments described herein allow a user to assess changes in local blood flow in microvasculature in real-time using conventional electrical techniques. Some embodiments provide a closed-loop system that allows calibrated doses of electrical stimulation to be delivered in a deep brain stimulation (DBS) system depending on blood flow changes (in specific regions of the brain) being fed back to a controller. The approach described here is readily translatable with very minimal changes to existing hardware. Such closed-loop systems will improve the accuracy of electrode placement in DBS surgery and potentially reduce surgery time, optimize the delivery of electrical stimulation, increase battery life of implantable DBS systems, reduce post-surgical visits to medical practitioners and improve the quality of life of patients.

Abstract: Systems and methods to determine an electrochemical impedance spectrogram (EIS) rapidly in real time are provided. Embodiments described herein provide an approach to determine an EIS rapidly (e.g., much less than one second) over a wide band of frequencies. Since the EIS is a foundational diagnostic that is used in a wide variety of applications involving electrochemical events, the proposed approach will significantly impact a wide range of applications. Novel waveforms and systems analysis techniques are used to determine the electrochemical impedance over a wide range of frequencies simultaneously. Embodiments can be readily integrated into conventional electrochemical workstations and embedded devices. Other embodiments can be instantiated into custom-made hardware depending on the needs of a given application. The speed and resolution of the EIS obtained using this approach can be tailored to a wide variety of applications.

Abstract: A system and method for modulating optogenetic vagus neurons in a noninvasive and transcutaneous manner is disclosed. The system and method comprises a two-dimensional array of organic light emitting diodes (OLEDs), a voltage-generating unit, a control unit, and a feedback loop. The array is placed on a subject's outer ear. Because the array is flexible, it can be closely placed on the skin of the outer ear. The array can deliver optical therapy and monitor heart rate variability (HRV) of the subject simultaneously, and the pixels of the array can be individually addressed. The voltage-generating unit generates pulsed voltage to the OLEDs. The control unit is connected to the array and controls the array and therapeutic patterns. The feedback loop uses the HRV to identify the therapeutic patterns.

Abstract: Systems and methods for improved control and performance of cochlear implants are disclosed. In an embodiment, the audio environment is sampled, and a neural network determines suggested filter setting for the cochlear implant. The process is repeated such that, as the user moves through various audio environments having differing noise levels, satisfactory performance of the cochlear implant is maintained for the user.

Abstract: A microelectromechanical device and method for neuroprosthetics comprises microactuators and microelectrodes. The microelectrodes are to be positioned in a nerve bundle and bonded with the microactuators through an interconnect. The position of each of the microactuators can be individually tuned through control signals so that the microelectrodes are implanted at desired positions in the nerve bundle. The control signals are transmitted to the microactuators and generated with a open-loop or closed-loop control scheme that uses signals acquired by the microelectrodes from the nerve bundle as feedback.

Abstract: A system and method for modulating optogenetic vagus neurons in a noninvasive and transcutaneous manner is disclosed. The system and method comprises a two-dimensional array of organic light emitting diodes (OLEDs), a voltage-generating unit, a control unit, and a feedback loop. The array is placed on a subject's outer ear. Because the array is flexible, it can be closely placed on the skin of the outer ear. The array can deliver optical therapy and monitor heart rate variability (HRV) of the subject simultaneously, and the pixels of the array can be individually addressed. The voltage-generating unit generates pulsed voltage to the OLEDs. The control unit is connected to the array and controls the array and therapeutic patterns. The feedback loop uses the HRV to identify the therapeutic patterns.

Abstract: A microelectromechanical device and method for neuroprosthetics comprises microactuators and microelectrodes. The microelectrodes are to be positioned in a nerve bundle and bonded with the microactuators through an interconnect. The position of each of the microactuators can be individually tuned through control signals so that the microelectrodes are implanted at desired positions in the nerve bundle. The control signals are transmitted to the microactuators and generated with a open-loop or closed-loop control scheme that uses signals acquired by the microelectrodes from the nerve bundle as feedback.

Abstract: Systems and methods for stimulating neural tissue are disclosed. An array of optically emissive pixels is configured to deliver light to the neural tissue of a subject. Individual pixels within the array can be addressed to selectively illuminate a portion of the neural tissue when a neurological event occurs. The system can also include an array of microelectrodes in electrical communication with the array of pixels and a power source. A biocompatible substrate can be used to support the microelectrodes pixels, and the power source. A microelectrode circuit and a pixel circuit can also be supported by the biocompatible substrate.

Abstract: A micro-scale implantable bioelectronic medical device system that allows multichannel neurostimulation of peripheral nerve bundles so to affect a more localized and specific control over neuromodulation of body tissues and organs. Such systems can be used in medical therapeutic applications for the treatment of a wide variety of disorders of the human body and may be applied in the growing field of medical neuromodulation. Systems and processes may also provide a way of interfacing to nerve and muscle for purposes of the control of advanced robotic prosthetics as well as man-machine interfaces. Apparatus, systems and processes may be adapted in various embodiments to the stimulation of brain and other bioelectrically excitable tissues in the human body as well.

Abstract: Systems and methods for stimulating neural tissue are disclosed. An array of optically emissive pixels is configured to deliver light to the neural tissue of a subject. Individual pixels within the array can be addressed to selectively illuminate a portion of the neural tissue when a neurological event occurs. The system can also include an array of microelectrodes in electrical communication with the array of pixels and a power source. A biocompatible substrate can be used to support the microelectrodes pixels, and the power source. A microelectrode circuit and a pixel circuit can also be supported by the biocompatible substrate.