The basal ganglia and its role in Parkinson’s disease

Abstract

The basal ganglia consist of a collection of subcortical nuclei that play an essential role in the control of motor function but also too in cognition. These nuclei can in turn be divided according to their projections into input, output and intrinsic nuclei. The classical basal ganglia model was developed to explain the circuits within this structure. It consists of a direct pathway that promotes movement, an indirect pathway that inhibits movement and a dopaminergic pathway that modulates movement. Disorders are seen to arise due to a dysfunction in a part of the circuit. Such can be arranged in a spectrum that consists of hyperkinetic disorders on one side and hypokinetic disorders on the other. By identifying which parts of the circuit is dysregulated, one would be able to design therapies to elevate these symptoms.