This thesis investigated the nature of the deficit in story recall associated with temporal-lobe damage in the left hemisphere dominant for speech. The first three experiments examined whether excision of this region (1) slows the rate at which verbal material is processed, (2) reduces working-memory capacity, or (3) interferes with the integration of information across sentences. Left temporal lobectomy does not impair these aspects of the initial processing of stories, since on none of the above variables was the performance of left temporal-lobe groups deficient relative to that of normal control subjects, or patients with unilateral frontal- or right temporal-lobe removals. The fourth experiment examined the effect of left temporal lobectomy on how quickly a passage was forgotten after it had been learned to criterion. Although patients with such an excision took more trials to learn a story than did normal control subjects, only those patients with extensive left hippocampal removal were impaired when recalling this story 20 minutes later. These results highlight the role of the left hippocampus in the long-term maintenance of story information.

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