Content and temporal structure of autobiographical knowledge: remembering twenty-five seasons at the Metropolitan Opera.

Three experiments were designed to explore the structure and content of a well-defined subset of very long-term autobiographical memory. In Experiment 1, the author free-recalled in a single session details about the dates and casting of 284 opera performances seen at the Metropolitan Opera over a period of 25 seasons. Recall accuracy was measured by comparing the recall with the programs for each performance. Primacy and recency effects were prominent in recall of both temporal and casting details. Also, recall of performances was superior if the performances were included in the sequential structures of seasons in memory. Experiments 2 and 3 were designed to examine the effect of an opera performance's relative importance (or intensity) and opportunities for rehearsal of an opera performance on the author's free recall of the performance. In Experiment 2, importance/rehearsal opportunity was estimated from nine sources, including recordings, telecasts, tapes, and photograph books. In Experiment 3, the set of opera performances was rated and ranked by four opera experts on the dimension of intensity or importance of each performance. In both experiments, importance/rehearsal opportunity was related to superior recall of casting but not to recall of temporal details. Results suggest that detailed temporal structure in autobiographical memory is lost over time, whereas contents may be updated through various forms of rehearsal.