Huntington's disease (HD) is an inherited degenerative neurological condition, which means it affects the brain and results in selective brain cell death.

The regions of the brain that is mostly affected in HD are the basal ganglia and the frontal lobe which are responsible for motor movement control and coordination, cognition, personality and emotions.

Degeneration of these parts of the brain causes changes or affects the way people think, move, behave and express emotions. The following figure presents the differences of an HD-affected brain to that of an unaffected brain.

Unaffected Brain	HD Affected Brain