Isolated Impairment of Memory Following a Penetrating Lesion of the Fornix Cerebri

Abstract

Persistent memory problems were reported by a 39-year-old man who suffered a penetrating brain wound while serving in Vietnam 15 years earlier. Neuropsychological testing indicated an unusually isolated memory impairment. Computed tomography revealed transection of the columns of the fornix cerebri with no temporal-lobe involvement and minimal thalamic damage. We suggest that the fornix cerebri has a role in the maintenance of information accessibility to both encoding and recall during post-working memory processing and in the organization of verbal information during encoding and/or retrieval for declarative (recall) purposes. These processes are not essential for verbal recognition but can result in decrements on specific laboratory tasks and in social adjustment.