The monkey learns by first observing the movement, which activates its brain cells as if it was doing it. It's a lot like sports training, where trainers have athletes first imagine that they are performing the movements they desire.

Scientists 'reverse' memory loss 29. April 2007 Mental stimulation and drug treatment could help people with degenerative brain diseases such as Alzheimer's recover their memories, a study says. ... The study suggested that in people with degenerative brain diseases, memories were not erased from the brain, but rather could not be accessed because of the disease.