 The overall goal of the work in this laboratory is to develop and evaluate countermeasures
for space motion sickness (SMS), spatial disorientation and
sensorimotor disturbances associated with the microgravity
environment of space flight. In support of this goal a variety
of investigations are performed to better understand perceptual,
neurovestibular, and sensorimotor adaptation mechanisms.
Our research includes: (1) evaluation of the efficacy of
antimotion sickness medications and their effects on human
performance, (2) using virtual reality (VR) as a ground-based
model of the effects of microgravity on perception, spatial
orientation and sensorimotor functions, such as postural
control, eye-head and eye-hand coordination, (3) development
of countermeasures for the negative effects of microgravity
inflight and immediately postflight, and (4) evaluation of
different training methods to facilitate preflight adaptation.
 Image right: Device for Orientation and Motion Environments (DOME) Virtual
Reality System.
Image left: VR4 Head-Mounted Display (HMD)
The laboratory is equipped with two VR systems: (1) VR4 head-mounted display
(HMD), and (2) a 12 ft. spherical dome display called the
device for orientation and motion environments (DOME). In
addition, the laboratory houses the Tilt-Translation Device
(TTD), which is designed to examine the otolith tilt-translation
reinterpretation (OTTR) hypothesis, and to preadapt astronauts
to this new interpretation of otolith signals that occurs
during space flight. Evaluation of sensorimotor adaptive
responses to exposure to the VR devices and the TTD is accomplished
with: (1) Neurocom Equitest to evaluate postural control,
(2) binocular video-oculography system for eye movement  measurements,
and a (3) custom, computer-controlled target display for
visual and manual target acquisition.
Image right: Outside view of Tilt-Translation Device (TTD)
The Tilt-Translation Device in the
Preflight Adaptation Training facility was designed as
a ground-based analog to replicate the tilt-translation disturbances
following g transitions. Using this device, tilt chair
motion
is coupled with translation visual scene motion aligned
with the horizontal head axis, resulting in a visual-vestibular
mismatch in which both canals and otoliths signal tilt
while
vision does not. A new linear track in development will
provide an alternative paradigm during which the chair will
tilt
within an enclosure that will simultaneously translate
so that the resultant gravitoinertial force vector remains
 aligned
with the longitudinal body axis, resulting in a mismatch
in which the canals and vision signal tilt while the otoliths do not. The primary goals of this ground-based research investigation,
funded through NSBRI, are to explore physiological mechanisms
and operational implications of disorientation and tilt-translation
disturbances reported by crewmembers during and following
re-entry, and to evaluate a tactile prosthesis as a countermeasure
for improving control of whole-body orientation during
passive tilt and
translation motion paradigms.
Image left: Inside view of Tilt-Translation Device (TTD)
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