Authors:

TAYLOR, K.J, HENSON, R.N.A. & GRAHAM, K.S.

Reference:

Year of publication:

2006

CBU number:

6309

Abstract:

There is disagreement as to whether or not the hippocampus and surrounding cortex, in particular the perirhinal cortex, make distinct contributions to recognition memory in humans. To investigate this issue, we developed a novel forced-choice recognition memory test using pictures of unfamiliar faces and spatial scenes. At test, each studied item was presented either from the same view or a novel view (as compared with that shown during encoding), alongside a visually similar foil. Two patient groups were tested, one with selective bilateral damage to the hippocampus and a second with additional damage to medial temporal cortical regions surrounding the hippocampus, including the perirhinal cortex. When compared with age and education matched controls, both patient groups were significantly impaired on both the same and different view scene conditions. The hippocampal group, however, was unimpaired on the different view face condition, and was only mildly impaired on the same view face condition. This indicates that the hippocampus makes an essential contribution to memory for spatial scenes but not necessarily for faces. In contrast, the medial temporal lobe group was significantly impaired on both face conditions, indicating that the surrounding cortex, perhaps specifically the perirhinal cortex, is required for face recognition memory. These results demonstrate that the hippocampus is not always required for successful recognition memory performance and highlights the possibility that stimulus type may be a critical factor explaining some of the discrepancies found in the literature.