Visual selective attention deficits in patients with Parkinson's disease: A quantitative model-based approach

Seventeen Parkinson's disease (PD) patients with no dementia and a group of matched normal controls were administered a visual attention task. A set of quantitative models were developed and applied to the data (W.T. Maddox & F.G. Ashby, 1993). These models provided a description of the nature of individual error distributions. The results suggested that (a) PD patients were not differentially impaired as compared with normal controls in their ability to integrate information from 2 stimulus dimensions; (b) a significantly larger proportion of the PD patients as compared with normal controls showed deficits in selective attention; and (c) although a large subgroup of the PD patients showed selective attention deficits, another subgroup of PD patients was able to attend selectively in an optimal fashion. The possible neuropathological correlates of PD patients' selective attention deficits are discussed.