ABSTRACT

University of Washington School of Medicine, Seattle, Washington, U.S.A.

INTRODUCTION

Consistent with the clinical focus of this volume, this chapter first acquaints the reader with basic distinctions between the clinical ‘‘brain-behavior’’ disciplines, namely neuropsychology, behavioral neurology, and neuropsychiatry. After describing the most common approaches to neuropsychological evaluation and the goals of neuropsychological evaluation in Parkinson’s disease (PD), the chapter highlights the cognitive alterations most frequently accompanying PD and those that occur in and differentiate dementias seen in PD from other neurodegenerative conditions. A discussion of the impact of emotional comorbidity on cognition makes clear the importance of treating anxiety, depression, and psychiatric symptoms in optimizing the afflicted person’s functioning and quality of life. Both medical and surgical treatments, the latter enjoying a renaissance after a protracted, relative absence from the treatment armamentarium after the introduction of levodopa, have the potential to impact cognition. Only a sparse literature devotes itself to treatment-related neurobehavioral complications and less frequent improvements. The chapter concludes with a brief comparison of the most common cognitive alterations

accompanying parkinsonian and related syndromes, such as multiple system atrophy, progressive supranuclear palsy (Steele-Richardson-Olzewski syndrome), and essential tremor. Although the neuropsychological features in parkinsonian syndromes probably lack the specificity and sensitivity to be of differential diagnostic utility, the neurobehavioral differences observed among groups of patients with various disorders can guide diagnostic hypotheses and inform about the plural neurobehavioral roles of the basal ganglia.