Cognitive and Perceptual Impairments in Parkinson’s Disease Arising from Dysfunction of the Cortex and Basal Ganglia

Abstract

The basal ganglia are a major set of subcortical nuclei involved in the production of movement. Their importance was realized relatively early in clinical neurology when patients with lesions affecting these structures had motor deficits, such as slow movements or excessive ones including chorea. Although their precise functions have been debated and are still the subject of much research, we now believe the basal ganglia contain parallel pathways, which can stimulate or inhibit movement being generated by the cerebral cortex via their thalamo-cortical connections, rather than initiate movement per se. Knowledge and understanding of the basal ganglia are essential for interpreting the clinical symptoms and signs in a variety of movement disorders, for example, Parkinson's disease and Huntington's chorea.