Cognitive dysfunction in Parkinson’s disease

Abstract

This chapter considers both the ‘typical’ cognitive profile of Parkinson’s disease (PD) patients without dementia as well as the heterogeneity in cognitive change noted in several community samples. Some neuroimaging experiments that have demonstrated changes in brain metabolism and structure associated with specific cognitive deficits are described along with genetic studies that have tried to identify a basis for the differing levels of cognitive impairment within people with PD. The possible biological mechanisms underlying these changes are discussed. The clinical and pathophysiological basis of mild cognitive impairment in PD, which may indicate a risk of further decline and clinically relevant dementia, is considered and the issues surrounding neuropsychological assessment in PD are discussed. Guidelines for the diagnosis and management of cognitive impairment in PD are given.