ABSTRACT

A striking finding in the literature on human memory is the profound but selective deficit seen after damage to the hippocampus and related structures in the temporal lobes of the human brain. This pattern of deficits was first seen in patient H.M. (Scoville and Milner, 1957), and has now been replicated in the data of a large number of other patients with similar lesions. These patients show a dramatic deficit in the ability to acquire new explicit memories for the contents of specific episodes and events. For example, the ability to learn arbitrary word-pairs such as “LOCOMOTIYEDISHTOWEL” is drastically impaired. Normal subjects will learn such lists after a few presentations, so that whenever the first word of a pair is presented they will he able to recall the second word of each pair. But, H.M. and other similar amnesics may tail to learn even one pair after repeated presentations. There is also profound impairment in everyday memory abilities, such as the ability to learn names of new people, or the ability to remember important personal events and experiences.