Faculty Collaboration Database

Sensory percepts induced by microwire array and DBS microstimulation in human sensory thalamus. Brain Stimul 2018;11(2):416-422

Date

11/12/2017

Pubmed ID

29126946

Pubmed Central ID

PMC5803348

DOI

10.1016/j.brs.2017.10.017

Scopus ID

2-s2.0-85032918154 (requires institutional sign-in at Scopus site)   20 Citations

Abstract

BACKGROUND: Microstimulation in human sensory thalamus (ventrocaudal, VC) results in focal sensory percepts in the hand and arm which may provide an alternative target site (to somatosensory cortex) for the input of prosthetic sensory information. Sensory feedback to facilitate motor function may require simultaneous or timed responses across separate digits to recreate perceptions of slip as well as encoding of intensity variations in pressure or touch.

OBJECTIVES: To determine the feasibility of evoking sensory percepts on separate digits with variable intensity through either a microwire array or deep brain stimulation (DBS) electrode, recreating "natural" and scalable percepts relating to the arm and hand.

METHODS: We compared microstimulation within ventrocaudal sensory thalamus through either a 16-channel microwire array (∼400 kΩ per channel) or a 4-channel DBS electrode (∼1.2 kΩ per contact) for percept location, size, intensity, and quality sensation, during thalamic DBS electrode placement in patients with essential tremor.

RESULTS: Percepts in small hand or finger regions were evoked by microstimulation through individual microwires and in 5/6 patients sensation on different digits could be perceived from stimulation through separate microwires. Microstimulation through DBS electrode contacts evoked sensations over larger areas in 5/5 patients, and the apparent intensity of the perceived response could be modulated with stimulation amplitude. The perceived naturalness of the sensation depended both on the pattern of stimulation as well as intensity of the stimulation.

CONCLUSIONS: Producing consistent evoked perceptions across separate digits within sensory thalamus is a feasible concept and a compact alternative to somatosensory cortex microstimulation for prosthetic sensory feedback. This approach will require a multi-element low impedance electrode with a sufficient stimulation range to evoke variable intensities of perception and a predictable spread of contacts to engage separate digits.

Author List

Swan BD, Gasperson LB, Krucoff MO, Grill WM, Turner DA

Author

Max O. Krucoff MD Assistant Professor in the Neurosurgery department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Deep Brain Stimulation
Electrodes, Implanted
Feedback, Physiological
Female
Humans
Male
Somatosensory Cortex
Thalamus
Touch
Touch Perception