Age-related differences in upper limb proprioceptive acuity.

Although upper limb movements are known to be slower and more variable in elderly persons, the extent to which these changes are associated with deficits in movement-related sensory feedback is poorly understood, despite the importance of proprioception in the control of skilled movement. Age-related changes were examined with 22 participants (10 of M age 27 years and 12 of M age 75 years) in performance of an elbow position-matching task which varied in terms of interhemispheric transfer and/or the need to retrieve memory-based proprioceptive information. Matching errors were significantly greater, and movements more prolonged, and irregular in their time course in the elderly group than in the young group. Impaired performance in conditions requiring interhemispheric transfer and retrieval of memory-based proprioceptive information reflected the importance of cognitive processing during complex sensorimotor tasks. This novel matching paradigm provided a sensitive means of manipulating the demands of the task and may be an effective method for as sessing both cognitive and sensorimotor declines associated with aging.