title: When recognition memory is independent of hippocampal function.
abstract: Hippocampal damage has been thought to result in broad memory impairment. Recent studies in humans, however, have raised the possibility that recognition memory for faces might be spared. In five experiments we investigated face recognition in patients with hippocampal lesions (H) or large medial temporal lobe (MTL) lesions, including patients where neurohistological information was available. Recognition of novel faces was unequivocally intact in H patients but only at a short retention interval. Recognition memory for words, buildings, inverted faces, and famous faces was impaired. For MTL patients, recognition memory was impaired for all materials and across all retention intervals. These results indicate that structures other than the hippocampus, perhaps the perirhinal cortex, can support face recognition memory in H patients under some conditions. The fact that the faces were novel when recognition memory was intact does not fully account for our findings. We propose that the role of the hippocampus in recognition memory is related to how recognition decisions are accomplished. In typical recognition tasks, participants proceed by forming an association between a study item and the study list, and the recognition decision is later made based on whether participants believe the item was on the study list. We suggest that face recognition is an exception to this principle and that, at short retention intervals, participants can make their recognition decisions without making explicit reference to the study list. Important features of faces that might make face recognition exceptional are that they are processed holistically and are difficult to verbally label.
authors: Veterans Affairs San Diego Healthcare System, San Diego, CA 92161;Departments of Psychiatry.
authors: Christine N
authors: CN
authors: Smith
authors: The Center for Child and Adolescent Mental Health, Eastern and Southern Norway, 0405 Oslo, Norway;
authors: Annette
authors: A
authors: Jeneson
authors: Veterans Affairs San Diego Healthcare System, San Diego, CA 92161;Departments of Psychiatry.
authors: Jennifer C
authors: JC
authors: Frascino
authors: Department of Psychology and Neuroscience Center, Brigham Young University, Provo, UT 84604; and.
authors: C Brock
authors: CB
authors: Kirwan
authors: Department of Psychology and Neuroscience Center, Brigham Young University, Provo, UT 84604; andDepartment of Medicine, Pulmonary and Critical Care Division, Intermountain Medical Center, Murray, UT 84107.
authors: Ramona O
authors: RO
authors: Hopkins
authors: Veterans Affairs San Diego Healthcare System, San Diego, CA 92161;Departments of Psychiatry,Neurosciences, andPsychology, University of California, San Diego, La Jolla, CA 92093; lsquire@ucsd.edu.
authors: Larry R
authors: LR
authors: Squire
mesh_terms: D006624:Hippocampus / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008568:Memory; D010364:Pattern Recognition, Visual; D012372:ROC Curve
keywords: amnesia; long-term memory