RETROGRADE MEMORY AFTER RUPTURE OF ANEURY SMS OF THE ANTERIOR COMMUNICATING ARTERY

The aim of this study was to investigate deficits of retrograde memory , semantic, autobiographical, and for famous events, associated with p refrontal, cingulate and subcortical lesions resulting from anterior c ommunicating artery rupture. Analyses were performed during the second ary phase post-stroke in 16 patients, and performances were compared t o those of an equivalent number of matched control subjects. Semantic investigations revealed a significant deficit in each task using evoca tion, more especially categorial and literal evocations, and the verba l subtests of the WAIS-R: vocabulary, information, comprehension, and similarities. Furthermore, the capacity to categorise was preserved. T he Crovitz paradigm, which evaluated the autobiographical memory showe d a severe deficit in the evocation of events associated with a precis e context in place and moreover in time, with a clear tendency to prod uce semantic responses, but without significant increase in confabulat ions. The questionnaire on famous events (1936-1985) did not document deficit in recognition and recall. Furthermore, the patients disorder was more severe in learning new information. Memory disorders were bes t explained by the severity of lesions in the mediobasal frontal and c ingulate cortices, but also by the subcortical injury. Significant cor relations were observed between the retrograde memory performance and ''frontal'' tasks, more especially the WCST; however, similar relation s were also documented between learning new information and ''frontal' ' performance. These data suggest that retrogade amnesia results from a selective impairment in accessing old memory representations, and th at cognitive processes more specifically altered have tight relations with the capacity to organize the search and to shift.