Acquisition of novel semantic information in lesion location

Two patients with severe global amnesia are described who differ in the ext ent to which they have acquired new semantic information. Patient SS, who h as extensive medial temporal lobe damage including the hippocampus as well as surrounding cortical areas, has failed to acquire virtually any new info rmation regarding vocabulary or famous faces that entered the public domain since the onset of his amnesia. In contrast, patient PS, who has a selecti ve lesion of the hippocampus proper, has gained a sense of familiarity of n ovel vocabulary and famous people, even though her effortful retrieval of t his new semantic knowledge remains impaired. These findings extend to amnes ia of adult onset, the proposal of Vargha-Khadem and colleagues that in pat ients with selective hippocampal injury, cortical areas surrounding the hip pocampus may play an important role in new semantic learning [Vargha-Khadem , F., Gadian, D.G., Watkins, K. E.: Connelly, A., Van Paesschen, W. and Mis hkin, M., regarding the importance of the subhippocampal cortices in the me diation of new semantic learning in children with hippocampal lesions, Scie nce, 1997, 277, 376-380]. (C) 2000 Elsevier Science Ltd. All rights reserve d.