What condition is characterized by the progressive breakdown of nerve cells in the brain?

The condition characterized by the progressive breakdown of nerve cells in the brain is Huntington's disease. This genetic disorder leads to the degeneration of neurons, particularly in areas of the brain associated with movement, cognition, and emotion. As the disease progresses, it causes a wide range of symptoms, including motor dysfunction, cognitive decline, and psychiatric issues. Huntington's disease is hereditary, caused by a mutation in the HTT gene, and typically manifests in mid-adulthood, although symptoms can appear earlier in some cases.

In contrast, while other conditions like Parkinson's and Alzheimer's disease also involve neuronal degeneration, they have distinct characteristics and mechanisms. Parkinson's primarily affects dopaminergic neurons and is primarily associated with movement-related symptoms. Alzheimer's, on the other hand, involves the buildup of amyloid plaques and tau tangles, leading to memory loss and cognitive decline. Multiple sclerosis is an autoimmune condition that affects the protective covering of nerves rather than directly causing cell death. Each condition has its own unique pathophysiology and symptomatology, highlighting the specificity of Huntington's disease in causing progressive nerve cell degeneration.