Research

Balance

  • Current Research
  • Previous Research

Overview

A three-time space shuttle commander uses the Galvanic vestibular stimulation (GVS) system during a space shuttle landing simulation. The GVS delivers small amounts of electricity to the vestibular nerve, which then sends the signals to the brain, resulting in sensorimotor disturbances that are similar to those experienced by astronauts when returning to Earth. (Photo courtesy of the Human Aerospace Laboratory at the Mount Sinai School of Medicine.) Click here for larger image.

Galvanic Vestibular Stimulation as an Analog of Post-Flight Sensorimotor Dysfunction

Galvanic Vestibular Stimulation as an Analog of Post-Flight Sensorimotor Dysfunction

The Galvanic vestibular stimulation (GVS) system delivers small amounts of current to a person's vestibular nerve, mimicking the sensorimotor disturbances that can affect an astronaut's ability to walk and stand and impact their ability to land a spacecraft, making it an excellent tool to train astronauts before missions. Mount Sinai School of Medicine's Dr. Steven Moore leads this National Space Biomedical Research Institute-funded project. (Photo courtesy of Eric Wolfe Photography.) Click here for larger image.

Principal Investigator:
Steven T. Moore, Ph.D.

Organization:
Mount Sinai School of Medicine

Spending significant time in reduced gravity can cause sensorimotor problems for astronauts. These problems can have an effect on docking and landing operations and post-landing activities.

Dr. Steven Moore has developed a prototype system that simulates post-flight sensorimotor effects. The system uses Galvanic vestibular stimulation (GVS), which uses electrodes behind the ear to safely induce the symptoms of post-flight sensorimotor disruption. The system accurately reproduces postural, locomotor, gaze and perceptual deficits observed in astronauts following short- and long-duration missions, without inducing significant motion sickness symptoms. Moore and colleagues seek to bring the system to operational readiness by answering three questions: What are the best operational parameters for using GVS; what is the long-term response to GVS; and how well does GVS reproduce post-flight deficits in shuttle landing performance.

NASA Taskbook Entry

Technical Summary

The NASA Small Assessment Team (SAT) and the NASA Human Research Program (HRP) Integrated Research Plan evaluated sensorimotor risks for future exploration-class missions. A high priority was placed on the development and validation of ground-based operational tests to determine the effects of long-term microgravity exposure on sensorimotor performance, particularly manned control or supervision of spacecraft during docking and landing maneuvers. Head-down bed rest (HDBR) was suggested as the ground-based analog with which to conduct these tests. However, our recent artificial gravity study has demonstrated that HDBR does not reproduce sensorimotor deficits observed following spaceflight.

There is currently no operational analog of post-flight sensorimotor effects, and the primary aim of this project is to deliver such a system to facilitate the sensorimotor risk assessments mandated by the NASA SAT and HRP, as well as for crew training and countermeasure development. To this end, we have developed a prototype ambulatory system that generates a reversible sensorimotor deficit.

The system uses Galvanic vestibular stimulation (GVS), which modulates afferent vestibular input with a pseudorandom current delivered via surface electrodes placed on the skin behind each ear. The GVS analog has been designed such that the sensorimotor perturbation delivered accurately reproduces postural, locomotor, gaze and perceptual deficits observed in astronauts following short- and long-duration missions, without inducing significant motion sickness symptoms. In this project, we aim to bring the GVS sensorimotor analog to operational readiness by answering the following critical questions:

  1. What are the optimal parameters for a single exposure to the GVS analog?

  2. What is the long-term response to GVS?

  3. How well does the GVS analog reproduce post-flight deficits in shuttle landing performance?

Earth Applications

Our Galvanic vestibular stimulation (GVS) paradigm disrupts normal functioning of the human vestibular system, essentially adding noise to veridical afferent information from the peripheral vestibular apparatus. In our studies, we have shown that GVS replicates the sensorimotor dysfunction observed in astronauts during re-entry and after flights (manual control, gait, gaze, and balance). The GVS approach may be useful for modeling spatial disorientation in commercial aviation. Another potential application is modeling of vestibular pathology.
This project's funding ended in 2012