What effect does Huntington's disease have on the brain?

Huntington's disease is a neurodegenerative disorder that primarily affects the brain's neurons, leading to their progressive breakdown. This degeneration occurs mainly in specific areas of the brain, such as the basal ganglia, which are crucial for coordinating movement and cognitive functions. As nerve cells deteriorate, individuals with Huntington's disease typically experience a range of symptoms, including cognitive decline, emotional disturbances, and motor dysfunction. This gradual loss of nerve cells contributes to the characteristic symptoms associated with the disease, such as involuntary movements (chorea), difficulty in voluntary movements, and cognitive decline.

The other options do not accurately represent the effects of Huntington's disease on the brain; instead, they suggest improvements or enhancements that are contrary to the realities faced by those affected by this condition.