Space, the vestibular system, and MIT's Man-Vehicle Laboratory.

On March 5, 2009, a symposium on Strategic Planning Activity on Aerospace Medical and Human Factors Challenges was held at the Man-Vehicle Laboratory (MVL) at the Massachusetts Institute of Technology. The program was divided into three sections: Aviation Human Factors, Sensorimotor Challenges in Space, and Earth and Clinical Applications. The symposium was held on the occasion of the 65th birthday of Dr. Charles M. Oman, the Director of the MVL; participants and MVL colleagues were invited to submit manuscripts for this special issue. The Man-Vehicle Laboratory was founded in 1962, with a goal of better defining the physiological and cognitive limitations of pilots and passengers of aircraft and spacecraft, and to optimize overall human-vehicle system effectiveness and safety. As part of this mission, providing a better understanding of the role that the vestibular system plays in motor and sensory processing, particularly during the skilled tasks involved in vehicular flight, has been an important part of the MVL mission (http://mvl.mit.edu/). The MVL has long had a close collaboration with NASA, initially to better model and understand the phenomenon of “Space Motion Sickness” (otherwise called “Space Adaptation Syndrome”). From its original emphasis on manual control and the role of motion in determining pilot reactions, MVL’s interest evolved to a broader concentration on posture, biomechanics, eye movements, motion sickness and the diagnosis of vestibular disorders, applying engineering techniques to attempt to better understand vestibular physiology, particularly in unusual environments. Experiments have been conducted in airplanes and in space as well as in the clinic and the laboratory. From the first measurements of vestibular adaptation to weightlessness to current emphasis on sensory-motor disturbances, studies have examined human perceptual, oculomotor and postural reactions to unusual gravito-inertial environments. Experimental sites have included over 10 space shuttle flights, the Russian MIR station and on the International Space Station. MVL investigators have also actively pursued mathematical modeling of sensorimotor processes, particularly the issue of adaptation of systems to altered environments. The papers in this Special Issue exemplify the broad scope of problems and approaches that characterize the MVL and the interests of Dr. Oman. The first paper, from Shinder and Taube, examines the neural basis of vestibular inputs to higher cortical centers that can provide insights into regions of the brain involved in self-motion awareness,heading and orientation,and the differentiation of “self” from the (usually-stationary) surroundings. In orbital flight, signals from the vestibular system continue to signal head rotations, but no longer signal “orientation with respect to gravity”. One sense that may “substitute” for orientation cues in space is the visual system, allowing the subject to orient with respect