Describe in detail about the Huntington's disease

The brain of a person who has died as a result of Huntington's disease or Alzheimer's disease will look abnormal even to the naked eyes. It will appear shrunken inwards from the skull; gyri (surface bumps) will look 'deflated' and the sulci (surface grooves) will be wider. Usually, however, researchers are less interested in the outward appearance of the brain at death than in the subtle changes that occur during, or even before, the development of overt signs and symptoms. In any case, the external appearance of the brain at post-mortem may be entirely normal, with damage or disease only apparent on closure inspection of internal structures of tissues.