Putamen in the context of "Basal ganglia"

Cholesteryl esters are a type of dietary lipid and are ester derivatives of cholesterol. The ester bond is formed between the carboxylate group of a fatty acid and the hydroxyl group of cholesterol. Cholesteryl esters have a lower solubility in water due to their increased hydrophobicity. Esters are formed by replacing at least one –OH (hydroxyl) group with an –O–alkyl (alkoxy) group. They are hydrolyzed by pancreatic enzymes, such as cholesterol esterase, to produce cholesterol and free fatty acids. They are associated with atherosclerosis.

Cholesteryl esters are found in human brains as lipid droplets which store and transport cholesterol. Increased levels of cholesteryl esters have been found in certain parts of the brain of people with Huntington's disease. Higher concentrations of cholesteryl esters have been found in the caudate and putamen, but not the cerebellum, of people with Huntington disease compared with levels in controls. Increase in cholesteryl esters has also been found in other neurological disorders like multiple sclerosis and Alzheimer's disease.

The striatum (pl.: striata) or corpus striatum is a cluster of interconnected nuclei that make up the largest structure of the subcortical basal ganglia. The striatum is a critical component of the motor and reward systems; receives glutamatergic and dopaminergic inputs from different sources; and serves as the primary input to the rest of the basal ganglia.

Functionally, the striatum coordinates multiple aspects of cognition, including both motor and action planning, decision-making, motivation, reinforcement, and reward perception. The striatum is made up of the caudate nucleus, the putamen, and the ventral striatum. The lentiform nucleus is made up of the larger putamen, and the smaller globus pallidus. Strictly speaking the globus pallidus is part of the striatum. It is common practice, however, to implicitly exclude the globus pallidus when referring to striatal structures.

The internal capsule is a paired white matter structure, as a two-way tract, carrying ascending and descending fibers, to and from the cerebral cortex. The internal capsule is situated in the inferomedial part of each cerebral hemisphere of the brain. It carries information past the subcortical basal ganglia. As it courses it separates the caudate nucleus and the thalamus from the putamen and the globus pallidus. It also separates the caudate nucleus and the putamen in the dorsal striatum, a brain region involved in motor and reward pathways.

The internal capsule is V-shaped in transection forming an anterior and posterior limb, with the angle between them called the genu.