Adaptation to direction-dependent visuo-motor rotations and its decay in younger and older adults.
We studied adaptation to a direction-dependent visuo-motor rotation in adults of early and late working age. For hand movements to the right, visual motion of the cursor on a monitor was rotated clockwise, for forward movements rotation of the cursor motion was zero, and for directions in-between rotation was intermediate. In contrast to previous studies, in which adaptation was more difficult (larger visuo-motor rotation, larger number of targets during practice) and the older age group was of higher age, we found no age-related deficit of adaptation. However, consistent with previous studies we found an age-related impairment of explicit knowledge of the visuo-motor rotation and no age-related differences of aftereffects. Across periods of not performing the task for 24 h and of performing the task for a prolonged period of time without visual feedback, we observed a decay of adaptation which did not depend on age. The present findings cast doubts on the prevalent interpretation of age-related impairments of adaptation in the absence of age-related changes of aftereffects as resulting from intentional strategic corrections, which become less efficient at higher age.
Heuer
Herbert
H
Institut für Arbeitsphysiologie an der Universität Dortmund, 44139 Dortmund, Germany. heuer@ifado.de
Hegele
Mathias
M
D000223:Adaptation, Psychological; D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000523:psychology*; D005246:Feedback; D005260:Female; D006225:Hand; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D010469:Perceptual Distortion; D011597:Psychomotor Performance; D012399:Rotation; D014796:Visual Perception