From‘s Boyd Stevens (Harold Perrineau) experiencing Parkinson’s disease symptoms was a significant part of his season 1 story, but it has been overlooked in From seasons 2 and 3. As defined by the World Health Organization, “Parkinson’s disease is a brain condition that causes problems with movement, mental health, sleep, pain and other health issues.” Common Parkinson’s disease symptoms include involuntary movements and tremors known as dyskinesias. The severity of symptoms varies between individuals, but cognitive impairment can also occur.

https://screenrant.com/from-season-3-boyd-parkinsons-disease-forget/