Eye Tracking Device (ETD)
Research Area: Nervous and Vestibular Systems
Expedition(s): 9, 11, 13, 14, 16
Principal Investigator(s): ● Andrew Clarke, PhD, Charité Universitätsmedizin,
Berlin, Germany
RESEARCH OBJECTIVES
The Eye Tracking Device (ETD) determines the influence of prolonged microgravity and the
accompanying vestibular (inner ear) adaptation on the orientation of Listing's Plane (a
coordinate framework, which is used to define the movement of the eyes in the head). This
study has important implications for understanding basic mechanisms of motor control in
microgravity and for rehabilitative training of neurological patients with impaired motor
control.
EARTH BENEFITS
This study has important implications in understanding basic mechanisms of motor control in
microgravity and for rehabilitative training of neurological patients with impaired motor
control.
SPACE BENEFITS
Examination of the orientation of the Listing’s Plane during the course of a prolonged space
mission is of particular interest; as on Earth, the Listing’s Plane appears to be dependent on
input from the vestibular system, ie, detected through the head position with relation to
gravity. By exposing the astronaut to the weightlessness of space, this experiment can follow
the subsequent adaptation of the astronaut’s vestibular system during the flight and after re-
entry.
RESULTS
Visual functions were observed in flight
for 31 astronauts under prolonged
microgravity conditions. The precision
and speed parameters of visual tracing
such as fixational rotations of the eyes
(saccades), smooth tracking of linear and
curved movements of a focal point
stimulus, and following a vertical
pendulum-like movement stimuli
became worse. In a number of cases, a
complete disintegration of the smooth
tracing reflex occurred as well as an
increase in the time taken to fix the gaze
on a target (by factors of 2 or more) and
decreased in the frequency of stimulus
tracking. During the initial period of
European Space Agency astronaut Thomas Reiter wears the
Eye Tracking Device on the International Space Station in- ESA image.