Two experiments were designed to investigate effects of cueing upon aptitude for shifting by patients with Parkinson's disease. Subjects executed in alternation two different components of a task set over successive items in a list. We compared the costs of shifting when the stimulus ensemble remained constant from trial to trial ("uniform" lists), with the case in which a change of stimulus ensemble cued each shift of task ("mixed" lists). Shift costs with mixed lists were significantly smaller than those with uniform lists (Exp. 1, ns=12). This suggests that patients with Parkinson's disease can benefit from cues about the stimulus ensemble in performing tasks. Patients' shifting performance was different from that of controls only in a reversal-shift condition of the previously consistent stimulus-response mappings (Exp. 2, ns= 12). This result suggests that patients with Parkinson's disease suffer from a specific but not a general deficit in ability to shift.
|Number of pages||13|
|Journal||Perceptual and Motor Skills|
|Issue number||3 PART 1|
|Publication status||Published - 1998 Dec 1|
All Science Journal Classification (ASJC) codes
- Experimental and Cognitive Psychology
- Sensory Systems