The Silver Springs monkey trial was the event that turned PETA into a national force. They targeted the research of a Dr. Taub whose research discovered neuroplasticity (brain restructuring).
https://www.newscientist.com/article/mg12517050-700-nerve-discovery-confuses-debate-on-laboratory-monkeys
Following on that was more research with the target of helping brain damaged individuals of whom stroke patients are a large portion. Brain plasticity and rehabilitation in stroke patients