IMPAIRED WORD-STEM PRIMING IN PATIENTS WITH TEMPORAL-OCCIPITAL LESIONS

In the word-stem priming test, words are presented (e.g., MOTEL, PARAD E), and later subjects are shown three-letter word stems (e.g., MOT, P AR) and asked to complete each stem with the first word that comes to mind. Word-stem priming, as well as other aspects of implicit memory, are intact in amnesic patients with medial temporal lesions. However, this form of priming has been shown to be impaired in patients with Al zheimer's disease, suggesting that damage to neocortical areas outside the medial temporal lobe contributes to impaired priming in these pat ients. To examine the role of posterior cortical areas on word-stem pr iming, we administered the test to patients with unilateral temporal-o ccipital lesions. Patients with temporal-occipital lesions exhibited s ignificantly impaired priming on this test. The findings suggest a cri tical role of the inferior posterior neocortex in the expression of th is form of implicit memory. (C) 1997 Elsevier Science Ltd.