Chorea

Source:  Chorea    Tag:  huntington chorea disease
Chorea (meaning "dance" in Greek) is the unintentional movements caused by Huntington's Disease. As I briefly explained before: as the mutated HTT gene eats away at the basal ganglia region of the brain, the person will lose control of their gait functions as well as their cognitive and emotional functions. Chorea is expressed in fidgety movements, and in milder cases will look as if they are intentional. In more advanced cases of HD the person can also have trouble swallowing, speaking and have interferences with their posture. Chorea is a symptom of multiple different diseases including Parkinson's Disease (A good example of Parkinson's Chorea is Michael J. Fox)
I learned this here
and here

Below is a good comparison of how quickly Huntington's Disease can advance in 1 year. This is Meghan Sullivan, officially diagnosed with HD in 2007 and you can see how quickly Huntington's Chorea developed and how her speech becomes severely interrupted.
1 year later
 Meghan Sullivan battled Early-Onset Huntington's Disease (or Juvenile Huntington's Disease) for 10 years but passed away May 12, 2014 at the age of 26 due to her disease.