Retrieval from semantic memory as a function of age.

Twenty-four subjects, 12 of whom were in the age range 18-30 years and 12 of whom were between 55-65 years, performed two semantic memory tasks. One task involved the recall of an instance from a designated category starting with a specified letter, and the second task required subjects to indicate whether a given work was or was not a member of a designated category (the recognition task). There was a differential effect of age on recall and recognition, the older subjects responding more slowly on the recognition task, but not on the recall task. The response times of the older subjects were less affected by the dominance of the to-be-retrieved information than were the younger subjects. These results suggested that subjects in the older age group may have retrieved information faster than the young subjects, but that they required longer to decide upon response.