ABSTRACT
Dr. P. was a well-liked teacher at a local school of music who consulted with an ophthalmologist when he experienced some peculiar visual difficulties. Dr. P. complained of frequently being unable to recognize his students. Actually, to be more precise, Dr. P. had difficulty recognizing his students when he first saw them, particularly when they were sitting still. However, he would immediately identify them when they spoke. The ophthalmologist could find nothing wrong with Dr. P.’s eyes or vision, in the conventional sense. Nonetheless, he referred Dr. P. on to a neurologist, Dr. Oliver Sacks. In his initial meeting with Dr. P., Dr. Sacks conducted a routine neurological exam, which was essentially normal. However, much to Dr. Sacks’s amazement, when leaving his office, Dr. P. “reached out and took hold of his wife’s head, tried to lift it off, to put it on. He had apparently mistaken his wife for a hat!” (Sacks, 1970, p. 11).
