The clusters of neurons interdigitate with a rich AChE matrix. Afferent pathways The striatum receives several major inputs. Cortical innervation is topographically organized and derives from all neocortical and allocortical levels. There is strong evidence for glutamate serving as the neurotransmitter in this pathway. Intralaminar thalamic nuclei.
Efferent pathways The striatum projects to two major areas.
Medium size, densely-spined striatal neurons are the major projection neuron of the striatum. These GABAergic neurons were originally thought to be interneurons. The globus pallidus and entopeduncular nucleus are the major projection. A GABAergic projection to the substantia nigra plays an important role in the regulation of movement. Loss of the striatonigral pathway occurs in Huntington's disease and is associated with wild, choreic gestures and cognitive decline.