The role of prediction and anticipation on age-related effects on smooth pursuit eye movements
Externally guided sensory-motor processes deteriorate with increasing age. Internally guided, for example, predictive, behavior usually helps to overcome sensory-motor delays. We studied whether predictive components of visuomotor transformation decline with age. We investigated smooth pursuit eye movements (SPEM) of 45 healthy subjects with paradigms of different degrees of predictability with respect to target motion onset, type (smoothed triangular, ramp stimulation), and direction by blanking the target at various intervals of the ramp stimulation. Using repetitive trials of SPEM stimulation, we could dissociate anticipatory and predictive components of extraretinal smooth pursuit behavior. The main results suggest that basic motor parameters decline with increasing age, whereas both anticipation and prediction of target motion did not change with age. We suggest that the elderly maintain their capability of using prediction in the immediate control of motor behavior, which might be a way to compensate for age-related delays in sensory-motor transformation, even in the absence of sensory signals.
prediction anticipation aging smooth pursuit target blanking