The Orienting of Visual Attention and Time Perception in Idiopathic Parkinson's Disease Patients and in Healthy Aging

• Published in: Motor control 2007-01, Vol.11, p.S38-S38
• Main Authors: Mota, A, Morgero, K, Piemonte, ME, Baldo, M V
• Format: Article
• Language: English
• ISSN: 1087-1640

Objective: To assess the effects of Parkinson's disease (PD) and healthy aging on voluntary visual attention and temporal order perception. Methods and Results: Two psychophysical experiments were performed. In experiment I, we studied the voluntary orienting of visual attention in a reaction time (RT) task. The subjects oriented their attention to an informative cue and responded as fast as possible to a target. We observed that PD patients had increased RT when compared with elderly and young subjects. In experiment II, we evaluated detectability (d') in a temporal order judgment task (TOJ), wherein two visual stimuli were presented with different intervals. The volunteers judged which stimuli appeared first. We observed that when the interval between stimuli decreased, 1) the young subjects maintained the d'; 2) the elderly subjects had a decreased d' in all intervals; and 3) the PD patients had the fastest decline of d' and reached the smallest values. Comparing the RT values and the ratio of correct responses in the TOJ task, we found a positive correlation between them. Conclusions: Aging induces deficits in voluntary visual attention and temporal order discrimination, which are more evident in PD. The positive correlation between the results of these two tasks suggests common mechanisms involving perceptual and motor aspects.