Vestibular Implants Tested in Human Subjects

Summary

The goal of this study is to improve the vestibular implant's ability to reduce the vestibular-dependent perceptual, postural, and visual symptoms that affect patients with severe peripheral vestibular damage. The long-term research plan is focused on exploring the three questions which must be answered to assess the clinical utility of a vestibular implant (VI) in vestibulopathic patients - i) how can information transfer from the VI sensors to the brain be optimized; ii) how does the three-dimensional angular velocity information provided by the VI interact in the brain with other sensorimotor (vision, otolith, efferent) signals; and iii) how effectively does the VI alleviate the behavioral deficits and subjective symptoms experienced by patients with severe vestibular damage. The current study will be used to focus on two key subsets of these questions. Over one year, the investigators will study approximately 5 patients who have severe bilateral vestibular damage and functioning VI's, which will focus on aim 1: how the angular velocity information sensed by the VI can be optimally transferred to the brain; and aim 2: how effectively the VI improves the clinical status of vestibulopathic patients when they receive acute and sub-acute (3 days) motion-modulated stimulation. In sum, the investigators aim to improve the efficacy of the VI in human subjects by developing new knowledge about how the brain processes motion cues provided by the VI and correlating this information with behavioral outcomes.

Conditions

• Vestibular Disorder
• Vestibular Ataxia
• Vestibular Loss, Bilateral

Interventions

DEVICE

Vestibular prosthesis/implant

The intervention is a vestibular prosthesis which our collaborators at the University of Geneva are implanting into the inner ear in deaf patients without vestibular function who are receiving a cochlear implant. The vestibular implant (VI) has three rate sensors and senses angular head velocity in three dimensions and provides this information to the brain by stimulation the afferent nerves innervating the three semicircular canals. Our goal is to use the VI to better understand how the brain processes this prosthetic information and uses it to generate meaningful behavioral responses including eye movements, postural control, and perception.

DEVICE

Vestibular Implant Stimulation

VI subjects will be studied before the implant is activated (pre) and then after it is turned on (acute On); this will take about 2 hrs. Then they will have 8 hours of motion-modulated VI stimulation while they actively explore the hospital environment, after studies will be repeated (chronic On). Each set of outcome experiments will be performed twice, once with and once without low-levels of stochastic noise added to the VI stimulation provided for the 8-hour period. The noise amplitude is tailored to each patient to maximize stochastic resonance so extraction \& integration of spatial signal provided by the VI will always be the first experiment, but the order of the subsequent outcome sessions (active/passive head rotations, tilt/translation motion discrimination and VOR behavioral changes \& postural control) will be randomized. VI subjects will participate in 4 full-day sessions, each separated by at least a month.

Sponsors & Collaborators

• Ohio State University

  collaborator OTHER

• University of Geneva, Switzerland

  collaborator OTHER

• Massachusetts Eye and Ear Infirmary

  lead OTHER

Study Design

Allocation

NA

Purpose

BASIC_SCIENCE

Masking

NONE

Model

SINGLE_GROUP

Eligibility

Min Age

18 Years

Max Age

65 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2019-08-01

Primary Completion

2021-01-31

Completion

2021-01-31

Countries

• United States
• Switzerland

Study Locations