Feedback-related processes during a time-production task in young and older adults

Objective: We examined whether the age-related decline in the integrity of the mid-brain dopamine system plays a role in the adaptation of precisely timed motor responses by feedback information. Methods: Participants performed a time-production task with feedback given after each trial. They were encouraged to use the feedback for improving temporal response accuracy. Event-related potentials to the feedback were analyzed. Results: Older participants performed poorer than the young. Overall, high response accuracy was more favoured following positive than negative feedback. Older participants performed even worse after negative feedback than the younger. The feedback-related negativity (FRN) was of lower amplitude for older vs. young participants. FRN amplitude correlated significantly with response accuracy only for the young group. Conclusions: The decreased response accuracy during time production of the older group may be related to a weakened fronto-striatal dopamine system and thus a reduced ability to use feedback information for improving temporal aspects of the motor response. Significance: The study points to difficulties especially for older participants to process error feedback, and it underlines the importance of positive feedback in order to improve temporal response accuracy. Suggestions can be drawn for the design of feedback information especially for older adults in motor learning environments. (C) 2008 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.