Abstract: An example apparatus includes a shell portion configured to be worn over a head of a subject. The shell portion defines a plurality of apertures. The apparatus also includes a plurality of spherical fiducial structures disposed on the shell portion. Each of the fiducial structures includes a first material doped with a second material. The second material is a contrast agent for magnetic resource imaging (MRI). The apparatus also includes a mounting structure disposed on the shell portion and configured to secure the shell portion to the head of the subject.

Abstract: This specification describes systems, methods, devices, and other techniques for activating muscle groups in a mammal using an implantable epidural electrical stimulation (EES) system, and for using spinal landmarks to determine implant locations for an EES probe. In some aspects, a first set of electrodes of an EES system is provided at a first set of locations on the dura mater of a spine of a mammal, the first set of locations on the dura mater corresponding to a first muscle group of the mammal, a second set of electrodes is provided at a second set of locations on the dura mater of the spine of the mammal, the second set of locations on the dura mater corresponding to a second muscle group of the mammal, and the first and second sets of locations on the dura mater are stimulated by electrically energizing the first and second sets of electrodes.

Abstract: Epidural electrical stimulation (EES) systems and techniques for accessing and locating targeted spinal cord segments are disclosed. In some examples, a method includes providing a first set of electrodes of an EES system at a first set of locations on the dura mater of a spine of a mammal, the first set of locations on the dura mater corresponding to a first muscle group of the mammal; providing a second set of electrodes of the epidural electrical stimulation system at a second set of locations on the dura mater of the spine of the mammal, the second set of locations on the dura mater corresponding to a second muscle group of the mammal; and stimulating the first and second sets of locations on the dura mater by electrically energizing the first and second sets of electrodes, respectively, thereby activating the first and second muscle groups in a coordinated manner.

Abstract: Systems, methods, and devices for generating multiple cyclic square-waveforms and sloped-edge square waveforms. Aspects of the techniques disclosed herein include applying the generated waveforms to an electrode used in voltammetry, e.g., to measure a level of a neurochemical in neural tissue. An electrode can be located in a solution, and an electrical stimulus applied to the solution through the electrode using a multiple cyclic square waveform. An electrical current response to the stimulus is measured, and a level of an analyte (e.g., dopamine or other neurochemical(s)) determined based on the electrical current response.

Abstract: This document provides methods and materials involved in detecting and delivering neurochemical signals, electrophysiological signals, ions, or combinations thereof within a mammal. For example, systems that can include one or more implantable devices containing probes configured to detect neurochemical signals (e.g., neurotransmitter concentrations), electrical signals, ions, or combinations thereof and one or more implantable devices containing electrodes and/or microfluidic delivery components configured to deliver neurochemical signals (e.g., neurotransmitters), electrical signals, ions, or combinations thereof to one or more locations within a mammal are provided.

Abstract: Techniques are described for determining a voltammogram that characterizes a result of a fast-scan cyclic voltammetry process. The FSCV process can be performed using a sensing apparatus at least partially immersed in a volume of blood of a mammal. A system can process the voltammogram to determine a concentration of a neurochemical in the volume of blood of the mammal.

Abstract: This specification describes systems, methods, devices, and other techniques for activating muscle groups in a mammal using an implantable epidural electrical stimulation (EES) system, and for using spinal landmarks to determine implant locations for an EES probe. In some aspects, a first set of electrodes of an EES system is provided at a first set of locations on the dura mater of a spine of a mammal, the first set of locations on the dura mater corresponding to a first muscle group of the mammal, a second set of electrodes is provided at a second set of locations on the dura mater of the spine of the mammal, the second set of locations on the dura mater corresponding to a second muscle group of the mammal, and the first and second sets of locations on the dura mater are stimulated by electrically energizing the first and second sets of electrodes.

Abstract: A surgical system includes a skull attachment device that includes a support base configured to seat against a skull of a patient and one or more pins extending from a bottom surface of the support base and configured to pierce the scalp to seat the skull attachment device against the skull. The surgical system also includes an interface disposed along a top surface of the support base and having a shape that compliments a profile of a mating feature of a stereotactic device for defining a position and an orientation of the stereotactic device with respect to the support base while the interface is engaged with the mating feature.

Abstract: This document provides methods and materials involved in assessing concentrations of analytes in an environment using a diamond-containing carbon electrode. For example, methods and materials for using FSCV or paired pulse voltammetry to discriminate analytes based on their adsorption characteristics to a diamond-containing carbon electrode are described herein.

Abstract: This document provides methods and materials involved in assessing concentrations of analytes in an environment using a diamond-containing carbon electrode. For example, methods and materials for using FSCV or paired pulse voltammetry to discriminate analytes based on their adsorption characteristics to a diamond-containing carbon electrode are described herein.

Abstract: This document provides methods and materials involved in detecting and delivering neurochemical signals, electrophysiological signals, ions, or combinations thereof within a mammal. For example, systems that can include one or more implantable devices containing probes configured to detect neurochemical signals (e.g., neurotransmitter concentrations), electrical signals, ions, or combinations thereof and one or more implantable devices containing electrodes and/or microfluidic delivery components configured to deliver neurochemical signals (e.g., neurotransmitters), electrical signals, ions, or combinations thereof to one or more locations within a mammal are provided.

Abstract: This document provides methods and materials involved in detecting and delivering neurochemical signals, electrophysiological signals, ions, or combinations thereof within a mammal. For example, systems that can include one or more implantable devices containing probes configured to detect neurochemical signals (e.g., neurotransmitter concentrations), electrical signals, ions, or combinations thereof and one or more implantable devices containing electrodes and/or microfluidic delivery components configured to deliver neurochemical signals (e.g., neurotransmitters), electrical signals, ions, or combinations thereof to one or more locations within a mammal are provided.

Abstract: This document provides methods and materials involved in detecting and delivering neurochemical signals, electrophysiological signals, ions, or combinations thereof within a mammal. For example, systems that can include one or more implantable devices containing probes configured to detect neurochemical signals (e.g., neurotransmitter concentrations), electrical signals, ions, or combinations thereof and one or more implantable devices containing electrodes and/or microfluidic delivery components configured to deliver neurochemical signals (e.g., neurotransmitters), electrical signals, ions, or combinations thereof to one or more locations within a mammal are provided.

Abstract: Techniques are described for determining a voltammogram that characterizes a result of a fast-scan cyclic voltammetry process. The FSCV process can be performed using a sensing apparatus at least partially immersed in a volume of blood of a mammal. A system can process the voltammogram to determine a concentration of a neurochemical in the volume of blood of the mammal.

Abstract: This document provides methods and materials involved in detecting and delivering neurochemical signals, electrophysiological signals, ions, or combinations thereof within a mammal. For example, systems that can include one or more implantable devices containing probes configured to detect neurochemical signals (e.g., neurotransmitter concentrations), electrical signals, ions, or combinations thereof and one or more implantable devices containing electrodes and/or microfluidic delivery components configured to deliver neurochemical signals (e.g., neurotransmitters), electrical signals, ions, or combinations thereof to one or more locations within a mammal are provided.

Abstract: This document provides methods and materials involved in assessing concentrations of analytes in an environment using a diamond-containing carbon electrode. For example, methods and materials for using FSCV or paired pulse voltammetry to discriminate analytes based on their adsorption characteristics to a diamond-containing carbon electrode are described herein.

Abstract: This document provides methods and materials involved in differentiating analytes detected using a FSCV method. For example, methods and materials for using paired pulse voltammetry to discriminate analytes based on their adsorption characteristics to an electrode (e.g., a carbon fiber electrode) are provided.

Abstract: This document relates to methods and materials involved in detecting neurochemical signals, electrophysiological signals, ions, or combinations thereof with brain tissue. For example, methods and materials for using probes to detect neurochemical signals (e.g., neurotransmitter concentrations), electrical signals, or combinations thereof during deep brain stimulation are provided.

Abstract: Materials and methods for using kinetic cyclic voltammetry to measure analyte levels and assess analyte kinetics.

Abstract: This document provides methods and materials involved in detecting and delivering neurochemical signals, electrophysiological signals, ions, or combinations thereof within a mammal. For example, systems that can include one or more implantable devices containing probes configured to detect neurochemical signals (e.g., neurotransmitter concentrations), electrical signals, ions, or combinations thereof and one or more implantable devices containing electrodes and/or microfluidic delivery components configured to deliver neurochemical signals (e.g., neurotransmitters), electrical signals, ions, or combinations thereof to one or more locations within a mammal are provided.