Enhancing astronaut performance using sensorimotor adaptability training

Abstract

Astronauts experience disturbances in balance and gait function when they return to Earth. The highly plastic human brain enables individuals to modify their behavior to match the prevailing environment. Subjects participating in specially designed variable sensory challenge training programs can enhance their ability to rapidly adapt to novel sensory situations. This is useful in our application because we aim to train astronauts to rapidly formulate effective strategies to cope with the balance and locomotor challenges associated with new gravitational environments—enhancing their ability to “learn to learn.” We do this by coupling various combinations of sensorimotor challenges with treadmill walking. A unique training system has been developed that is comprised of a treadmill mounted on a motion base to produce movement of the support surface during walking. This system provides challenges to gait stability. Additional sensory variation and challenge are imposed with a virtual visual scene that presents subjects with various combinations of discordant visual information during treadmill walking. This experience allows them to practice resolving challenging and conflicting novel sensory information to improve their ability to adapt rapidly. Information obtained from this work will inform the design of the next generation of sensorimotor countermeasures for astronauts.

Physiological and Functional Alterations after Spaceflight and Bed Rest

“…Further, results from recent neurophysiological studies indicate that when vestibular information becomes unreliable, supplemental information like proprioception is up-weighted to maintain control of posture and locomotion ( 81 , 82 ). Its role in balance and postural control may be large enough that a well-optimized inflight proprioceptive countermeasure designed to maintain balance function coupled with preflight sensorimotor adaptability training ( 99 ) could protect crewmembers enough to perform critical mission tasks. This is a particularly important finding, because historically, it has been believed that vestibular changes were predominantly responsible for the deficits in balance and postural control.…”

Neural correlates of multi-day learning and savings in sensorimotor adaptation

“…In addition, we examined individual neural predictors of savings across test sessions, by identifying areas in which activation levels correlated with individual differences in the extent of multi-day savings. The prospect of predicting at the individual level who will show most savings of adaptation could have important implications for training programs that facilitate astronaut adaptation to novel environments 22 , 23 and rehabilitation 24 . We hypothesized that savings would show more neural overlap with early than with late adaptation, on the basis of recent literature linking savings to explicit recall of a previously successful adaptation strategy 14 , 15 .…”

The contributions of occupational science to the readiness of long duration deep space exploration

“…Helen Cohen, an occupational therapist, was part of a team that developed a training program aimed to improve the ability of astronauts to adapt to new sensory environments called the Sensorimotor Adaptability (SA) Training [28]. By assisting crew members in learning how to solve sensorimotor, balance, and/or locomotor challenges, adaptation to this extreme environment can be increased.…”

“…Sensorimotor Ability Training involves walking on a treadmill that is mounted on a six degree of freedom motion base in front of a screen that provides visual stimuli. It has been proven to improve locomotor adaptability, and stability, which reduces energy expenditure [28]. Ironically, one of the very few occupational therapists involved with NASA is involved in this training program.…”