The person who I consider to be the most famous psychology human subject passed away last December, at the age of 82, after being studied since he was 27 years old. It was at that time in 1953 that H.M. (as he was known until his death) lost his ability to store new memories as a result of a surgical procedure that was done to treat severe epilepsy. While the surgery was successful in preventing the seizures that had incapacitated H.M., it had a devastating effect on the rest of his life. It was thought at first that he was no longer able to form any new memories, but the work of Brenda Milner revealed that he was able to form some types of new memory, just not the kind that we usually think of. He could learn new skills, but he would not be able to say when and where he learned the skill or even that he had the skill. It would only be revealed in his actions.
When H.M. died, and it was revealed that his initials stood for Henry Molaison, it was also revealed that his brain was to be studied at UC San Diego, and that the public would be able to view the process and the resulting brain images at the Brain Observatory (see description of the HM project here). I was delighted to find the link to a NOVA episode that featured this work. It's definitely worth 10 minutes of your time! You can get there by clicking here: NOVA
I'm sure that if Mr. Molaison had been taught to knit after his surgery, he would have retained that skill and made some pretty awesome projects!