An elongated device adapted for insertion, including self-insertion, through the body, especially the skull is disclosed. The device has at least one effector or sensor and is configured to permit implantation of multiple functional components through a single entry site into the skull by directing the components at different angles. The device may be used to provide electrical, magnetic, and other stimulation therapy to a patient's brain. The lengths of the effectors, sensors, and other components may completely traverse skull thickness (at a diagonal angle) to barely protrude through to the brain's cortex. The components may directly contact the brain's cortex, but from there their signals can be directed to targets deeper within the brain. Effector lengths are directly proportional to their battery size and ability to store charge. Therefore, longer angled electrode effectors not limited by skull thickness permit longer-lasting batteries which expand treatment options.

An electrode configured to provide electrical contact with skin of a subject is provided. The electrode includes an electrode body configured to be removably coupled with the skin of the subject and to receive electrical signals from and/or transmit electrical signals to the skin of the subject, and an electrical coupling that facilitates coupling the electrode to an external computing system. The electrode body includes a conductive silicone material configured to enable uptake or diffusion of moisture from the skin of the subject over which the electrode body is disposed; and a detergent configured to facilitate a flow of ions through the conductive silicone material.

An apparatus comprising: at least one electrode, having a first potential, arranged to sense a biosignal; a conductive shield provided over the at least one electrode where the conductive shield is configured to be driven to a second potential wherein the second potential is equivalent to the first potential plus a multiple of an inverted common mode voltage; and wherein the conductive shield is coupled to a drain to enable triboelectric charges to be dissipated.

An electrode system for neurological monitoring is disclosed, including a housing with a recess dimensioned to hold an electrode. A conductive is applied to said electrode to limit direct contact by said electrode to a patient's skin. The recess defines a wall in said housing that engages the patient's skin. A thin bead of adhesive applied to the top surface of the wall secures the housing, and therefore the electrode, to the patient. Finer electrical conductor wires in a more flexible insulator lead from the electrode to a connector that fits into a neurological monitoring amplifier.

A method may include identifying a simulated three-dimensional representation corresponding to an internal anatomy of a subject based on a match between a computed two-dimensional image corresponding to the simulated three-dimensional representation and a two-dimensional image depicting the internal anatomy of the subject. Simulations of the electrical activities measured by a recording device with standard lead placement and nonstandard lead placement may be computed based on the simulated three-dimensional representation. A clinical electrogram and/or a clinical vectorgram for the subject may be corrected based on a difference between the simulations of electrical activities to account for deviations arising from patient-specific lead placement as well as variations in subject anatomy and pathophysiology.

One variation of a method for testing contact quality of electrical-biosignal electrodes includes: outputting a drive signal through a driven electrode, the drive signal comprising an alternating-current component oscillating at a reference frequency and a direct-current component; reading a set of sense signals from a set of sense electrodes at a first time; calculating a first combination of the set of sense signals; calculating a first direct-current value comprising a combination of the first combination and the direct-current component of the drive signal at approximately the first time; and at a second time succeeding the first time, shifting the direct-current component of the drive signal output by the driven electrode to the first direct-current value.

One variation of a method for testing contact quality of electrical-biosignal electrodes includes: outputting a drive signal through a driven electrode, the drive signal comprising an alternating-current component oscillating at a reference frequency and a direct-current component; reading a set of sense signals from a set of sense electrodes at a first time; calculating a first combination of the set of sense signals; calculating a first direct-current value comprising a combination of the first combination and the direct-current component of the drive signal at approximately the first time; and at a second time succeeding the first time, shifting the direct-current component of the drive signal output by the driven electrode to the first direct-current value.

In general, innovative aspects of the subject matter described in this specification can be embodied in an electrode headset and methods of using an electrode headset. An exemplary electrode headset includes a head covering, an electrode assembly, and a plurality of electrodes. The head covering has a plurality of holes and the electrode assembly includes a plurality of first connectors arranged to align with the plurality of holes of the head covering. Each electrode has a second connector configured to releasably mate with one of the first connectors of the electrode assembly through one of the plurality of holes of the head covering.

A system and method to extract the timing of ECG events without reliance on ECG. The system and method are based on effects of scalp pulsation (due to blood flow) on electrode location. The electrodes in the system with the closest proximity to the facial arteries are re-referenced to create a [Mean Left-Mean Right] signal (LRM). A constrained peak detection algorithm is then used to find the BCG events. Finally, an automatic error checking and correction algorithm based on inter-beat timing is applied.

Devices, methods and systems for transmitting signals through a device located in a blood vessel of an animal, for stimulating and/or sensing activity of media proximal to the device, wherein the media includes tissue and/or fluid.