Impaired recall of verbal material following rupture and repair of an anterior communicating artery aneurysm

Abstract

This paper presents a detailed investigation of the memory impairment suffered by a patient, ROB, following the rupture and repair of an anterior communicating artery aneurysm that damaged her left hemisphere. ROB is severely impaired on standard tests of verbal recall such as paired-associate learning and memory for prose passages. Nevertheless she performs normally on both versions of Warrington's (1984) recognition memory test, and on tests that require recall of visuo-spatial material. She also shows no evidence of confabulation. The discrepancy between recall and recognition performance persists even when attempts are made to ensure that the two types of test are equally “difficult” (cf. Calev, 1984). The impairment does not seem to be caused by inappropriate encoding strategies, since recall performance is not improved by imagery instructions or by levels of processing manipulations (Craik&Tulving, 1975). She also performs normally on implicit memory tests regardless of whether they involve data-driven or conceptdriven retrieval processes (cf. Roediger, 1990a; 1990b). It is argued that her recall problems reflect an inability to set up effective retrieval strategies that would enable her to access information stored in episodic memory.