Donald E. Parker, Ph.D.

Donald E. Parker, Ph.D.

Curriculum Vitae

After working for 40 years as a scientist and professor, I've accumulated numerous titles currently including: Affiliate Professor, Department of Otolaryngology - Head and Neck Surgery, University of Washington, Faculty Associate, Human Interface Technology Laboratory, University of Washington; Professor Emeritus, Department of Psychology, Miami University, Ohio.

Honors that I've received include the Space Act Award in 1993, election to membership in the International Academy of Astronautics in 1985 and selection as Alternate Payload Specialist for Spacelab SL-1 Mission in 1978.

I've devoted most of my career to studying responses evoked by vestibular and auditory stimulation With colleagues at Johnson Space Center, I examined eye movements and perceived self-motion following prolonged exposure to microgravity and was the first to report that perceived self-translation can be elicited by roll or pitch head motions during landing and immediately postflight. These observations led to the tilt-translation reinterpretation model of sensory-motion adaptation to weightlessness and to development of apparatus, the Tilt-Translation Device and procedures to "preadapt" astronauts to some features of the stimulus rearrangement experienced during weightless space flight.

Current Research Interests

I'm currently attempting to develop materials and procedures for assessing vestibular contributions to spatial cognition. My recent research has focused on self-motion perception reporting.In a study published in 1998, my colleagues and I found that self-motion reports were not superior using animations relative to those recorded when subjects selected from written descriptions. In order to implement that study, all subjects were trained to use a self-motion vocabulary. Failure to observe an advantage for the animation procedure may have been due to the vocabulary training. Phillips and I (Parker & Phillips, 1999) recently described a new procedure for assessing self-motion perception using real-time computer-generated animations. This procedure doesn't require the motion vocabulary training used earlier. Following cross coupled angular acceleration, we observed vertical eye movements in the expected direction; however, perceived self-motion was in the expected direction only for about 50% of trials. It's important to note that self-motion assessed by real-time computer animations was quite reliable (r > 0.8). Use of perceptual procedures to facilitate assessment of patients who suffer from equilibrium system disturbance is in its infancy. We have developed what appears to be a reliable and valid procedure for examining complex self-motion. Dr. Phillips and I plan to compare eye movement and self-motion perception assessments in adults and children who suffer from balance disorders.

A second line of research examines visual-vestibular interaction. Using a cross-over procedure developed with former graduate students Dr. Ted Carpenter-Smith and Dr. Jerry Prothero, we can examine the relative influence of visual and inertial cues on perceived self-motion. Preliminary observations suggest that we may be able to detect response asymmetries, which would allow us to identify whether the left or right horizontal semicircular canal is damaged. If the procedure works for horizontal canals, extension to vertical canal assessment, which is very difficult using currently available procedures, is quite likely. The cross-over asymmetry procedure holds a promise for significant clinical applications

Finally, in response to documented cases of astronauts experiencing disorientation in space, Dr. Max Wells and I have submitted a proposal to NASA for development of "Virtual Gravity" (VRg). One instantiation of VRg would use a see-through head-mounted display (HMD), wireless communication, and a body-worn computer to overlay a space-stabilized independent visual background over a portion of the wearer's field-of-view. Our first goal will be to evaluate VRg in virtual mazes that permit some orientation disturbances similar to those encountered in microgravity.

Current Research Support

NASA Grant NAG5-407, Self -motion perception assessed by computer-made animations.