Impaired inference in a case of developmental amnesia.
Amnesia is associated with impairments in relational memory, which is critically supported by the hippocampus. By adapting the transitivity paradigm, we previously showed that age-related impairments in inference were mitigated when judgments could be predicated on known pairwise relations, however, such advantages were not observed in the adult-onset amnesic case D.A. Here, we replicate and extend this finding in a developmental amnesic case (N.C.), who also shows impaired relational learning and transitive expression. Unlike D.A., N.C.'s damage affected the extended hippocampal system and diencephalic structures, and does not extend to neocortical areas that are affected in D.A. Critically, despite their differences in etiology and affected structures, N.C. and D.A. perform similarly on the task. N.C. showed intact pairwise knowledge, suggesting that he is able to use existing semantic information, but this semantic knowledge was insufficient to support transitive expression. The present results suggest a critical role for regions connected to the hippocampus and/or medial prefrontal cortex in inference beyond learning of pairwise relations. © 2016 The Authors Hippocampus Published by Wiley Periodicals, Inc.
Rotman Research Institute, Baycrest, 3560 Bathurst St, Toronto, Ontario, Canada, M6A 2E1.
Maria C
MC
D'Angelo
Rotman Research Institute, Baycrest, 3560 Bathurst St, Toronto, Ontario, Canada, M6A 2E1.|Department of Psychology, York University, 4700 Keele Street, Toronto, Ontario, Canada, M3J 1P3.
R Shayna
RS
Rosenbaum
Rotman Research Institute, Baycrest, 3560 Bathurst St, Toronto, Ontario, Canada, M6A 2E1. jryan@research.baycrest.org.|Department of Psychology and Department of Psychiatry, University of Toronto, 27 King's College Cir, Toronto, Ontario, Canada, M5S 1A1. jryan@research.baycrest.org.
Jennifer D
JD
Ryan
D000647:Amnesia / Q000000981:diagnostic imaging / Q000209:etiology / Q000523:psychology*; D001921:Brain / Q000000981:diagnostic imaging; D006801:Humans; D007600:Judgment; D007858:Learning; D008297:Male; D008568:Memory; D009483:Neuropsychological Tests; D012660:Semantics; D055815:Young Adult
developmental amnesia; memory; semantic memory; transitivity