title: Memory for items and relationships among items embedded in realistic scenes: disproportionate relational memory impairments in amnesia.
abstract: OBJECTIVE
  The objective of this study was to examine the dependence of item memory and relational memory on medial temporal lobe (MTL) structures. Patients with amnesia, who either had extensive MTL damage or damage that was relatively restricted to the hippocampus, were tested, as was a matched comparison group. Disproportionate relational memory impairments were predicted for both patient groups, and those with extensive MTL damage were also expected to have impaired item memory.
  
  
  METHODS
  Participants studied scenes, and were tested with interleaved 2-alternative forced-choice probe trials. Probe trials were either presented immediately after the corresponding study trial (Lag 1), 5 trials later (Lag 5), or 9 trials later (Lag 9) and consisted of the studied scene along with a manipulated version of that scene in which 1 item was replaced with a different exemplar (item memory test) or was moved to a new location (relational memory test). Participants were to identify the exact match of the studied scene.
  
  
  RESULTS
  As predicted, patients were disproportionately impaired on the test of relational memory. Item memory performance was marginally poorer among patients with extensive MTL damage, but both groups were impaired relative to matched comparison participants. Impaired performance was evident at all lags, including the shortest possible lag (Lag 1).
  
  
  CONCLUSIONS
  The results are consistent with the proposed role of the hippocampus in relational memory binding and representation, even at short delays, and suggest that the hippocampus may also contribute to successful item memory when items are embedded in complex scenes.
authors: Department of Psychology, University of Wisconsin, Milwaukee.
authors: Deborah E
authors: DE
authors: Hannula
authors: Department of Psychology, University of Iowa.
authors: Daniel
authors: D
authors: Tranel
authors: Dornsife Cognitive Neuroscience Imaging Center and Brain and Creativity Institute, University of Southern California.
authors: John S
authors: JS
authors: Allen
authors: Department of Psychology, Saint Louis University.
authors: Brenda A
authors: BA
authors: Kirchhoff
authors: Department of Psychology, University of Wisconsin, Milwaukee.
authors: Allison E
authors: AE
authors: Nickel
authors: Department of Psychology, University of Illinois, Urbana-Champaign.
authors: Neal J
authors: NJ
authors: Cohen
mesh_terms: D000328:Adult; D000647:Amnesia / Q000523:psychology*; D016022:Case-Control Studies; D005260:Female; D006624:Hippocampus; D006801:Humans; D008297:Male; D008568:Memory; D008569:Memory Disorders / Q000523:psychology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D013702:Temporal Lobe