Therapeutic Effects of Electrical Vestibular Stimulation (EVS) on Balance and Gait

Condition(s) studied

Investigational drug(s) / intervention(s)

electrical vestibular stimulation (EVS): EVS involves electrically activating the vestibular nerves by passing small electrical currents through electrodes placed on the mastoid processes (behind the ears) via battery powered, constant current isolated stimulators.

Sham Comparator: No current is applied during EVS treatment

Study summary

The aim of the study to is determine the safety, feasibility, efficacy, and persistence of non-invasive EVS to improve balance and gait performance in healthy individuals across the lifespan. Specifically, our objective is to measure balance and gait performance before, during and after exposure to single sessions and across repeated sequences of EVS at multiple study partner sites.

Eligibility

Primary outcome measure(s)

• Postural Sway Measure of Balance Performance — From enrollment through the end of treatment and up to 6 months post treatment
  Postural sway will be calculated from acceleration profiles of the head measured using data from a head-mounted accelerometer in eyes open and eyes closed conditions. The raw acceleration signals are in units of G. The outcome measure is expressed as a sway power value (in Watts). Sway power measured during static standing has been shown to be a precise, quickly administered assessment of balance performance with excellent sensitivity in the identification of older adult fallers. We will complete the above 2-minute postural sway assessment (60 seconds eyes open followed by 60 seconds eyes closed) immediately before and after each of the 18 EVS treatment sessions in order to track each study participant's changes in balance performance following each treatment session and the cumulative change following completion of the 18 session treatment protocol.
• Sensory Integration Measure of Balance Performance — From enrollment through the end of treatment and up to 6 months post treatment
  Sensory integration will be calculated from acceleration profiles of the head measured using data from a head-mounted accelerometer in eyes open and eyes closed conditions. The raw acceleration signals are in units of G. The outcome measure is calculated using a frequency spectrum analysis of the normalized contributions of the three sensory inputs (visual, vestibular, proprioceptive) to balance control. Sensory integration measured during static standing using wearable sensors or computerized dynamic posturography has been shown to be a precise, quickly administered assessment of sensory contributions to balance control with excellent sensitivity in the identification of sensory impairments that disrupt balance in older adults. Sensory reweighting will be calculated using the head acceleration data from the above 2-minute postural sway assessment (60 seconds eyes open followed by 60 seconds eyes closed) immediately before and after each of the 18 EVS treatment sessions in order to tr
• Gait Velocity Measure of Gait Performance — From enrollment through the end of treatment and up to 6 months post treatment
  Dynamic gait performance will be measured using data from a head-mounted accelerometer. The raw acceleration signals are in units of G. For dynamic gait tasks, the outcome measures will be the peak walking speed (in Meters per Second) achieved over a set of pre-defined distances from 3 meters to 100 meters. Wearable sensor-based gait velocity tests are widely used in research for older adults with and without pathology, and have norm referenced values and robust clinimetric properties. The above gait velocity measurements will be carried out prior to the first EVS treatment session and following the final (18th) EVS treatment session in order to track the cumulative change in each study participant's gait performance following completion of the 18 session treatment protocol.
• Gait Cadence Measure of Gait Performance — From enrollment through the end of treatment and up to 6 months post treatment
  Dynamic gait performance will be measured using data from a head-mounted accelerometer. The raw acceleration signals are in units of G. For dynamic gait tasks, the outcome measures will be gait cadence (in Steps per Second) over a set of pre-defined distances from 3 meters to 100 meters. Wearable sensor-based gait cadence tests are widely used in research for older adults with and without pathology, and have norm referenced values and robust clinimetric properties. The above gait cadence measurements will be carried out prior to the first EVS treatment session and following the final (18th) EVS treatment session in order to track the cumulative change in each study participant's gait performance following completion of the 18 session treatment protocol.
• Step Length Measure of Gait Performance — From enrollment through the end of treatment and up to 6 months post treatment
  Dynamic gait performance will be measured using data from a head-mounted accelerometer. The raw acceleration signals are in units of G. For dynamic gait tasks, the outcome measures will be step length (in Meters) over a set of pre-defined distance from 3 meters to 100 meters. Wearable sensor-based step length tests are widely used in research for older adults with and without pathology, and have norm referenced values and robust clinimetric properties. The above step length measurements will be carried out prior to the first EVS treatment session and following the final (18th) EVS treatment session in order to track the cumulative change in each study participant's gait performance following completion of the 18 session treatment protocol.
• Step Trajectory Measure of Gait Performance — From enrollment through the end of treatment and up to 6 months post treatment
  Dynamic gait performance will be measured using data from a head-mounted accelerometer. The raw acceleration signals are in units of G. For dynamic gait tasks, the outcome measures will be the distribution of head trajectories during each step (in Angular Degrees) over a set of pre-defined distances from 3 meters to 100 meters. Wearable sensor-based step trajectory tests are widely used in research for older adults with and without pathology, and have norm referenced values and robust clinimetric properties. The above step trajectory measurements will be carried out prior to the first EVS treatment session and following the final (18th) EVS treatment session in order to track the cumulative change in each study participant's gait performance following completion of the 18 session treatment protocol.

Trial sites (4)