Saturday, May 16, 2009

Putamen

The putamen is a dark, grey structure, which is situated in the outer and lateral portion of the lenticular nucleus, which, in turn, is part of the basal ganglia that is at the base of the cerebrum. Together with the globus pallidus, it forms the lenticular nucleus. The putamen and caudate nucleus also constitute the dorsal striatum, which is one of the structures that comprises the basal ganglia. Through various pathways, the putamen is connected to the substantia nigra and globus pallidus.

The main function of the putamen is to regulate movements and influence various types of learning. It employs dopamine to perform its functions. The putamen also plays a role in degenerative neurological disorders, such as Parkinson's disease. The caudate works with the putamen to receive the input from cerebral cortex. They can be considered the "entrance" to the basal ganglia. The nucleus accumbens and medial caudate receive input from frontal cortex and limbic regions. The putamen and caudate are jointly connected with the substantia nigra, but most of their output goes to the globus pallidus.