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Jack joins amputees trying to find out why they feel sensations in their missing limbs.
Dr Jack meets extreme risk taker Matthew Adams. Will tests at the University of Cambridge show that Matthew has a different brain from non-risk taking Jack?
Jack meets a man who has bizarre hallucinations and witnesses cutting edge surgery.
Dr Jack meets a man who has defied all odds by miraculously recovering from severe brain damage, after a car crash left him lying in a coma for three months.