PD Guide

Cognitive Symptoms

Though classified as a movement disorder, PD also affects thinking, learning, processing speed, reasoning, and other cognitive abilities. Cognitive symptoms present in a range from mild impairments including early mild frontal-executive dysfunction and memory deficits to more acute deficits such as bradyphrenia and dementia (Levin and Katzen, 2005; Rippon and Marder, 2005; Caviness et al., 2007). Community-based studies suggest that 30-40% of PD patients will develop clinically-defined dementia (Poewe, 2008).