Avoidance conditioning in amnesia: a single case experimental study.

We present a single case study of avoidance conditioning in a seriously amnesic patient with bilateral ischemic lesions of the brain. A four-path maze was used for conditioning. The procedure consisted in an aversive stimulus that the patient received every time he traced one of the four maze-paths connected to an electric shock generator with a stylus. Using a single case experimental design A-B-A, we found that the patient learned to avoid the path connected to the electric shock, although he never showed awareness of this. Our study confirms once again that conditioning is one of the residual learning capabilities in amnesic patients. Different neural systems are probably involved in conditioning processes.