Sparing of the familiarity component of recognition memory in a patient with hippocampal pathology.
Subject KN has a persistent anterograde amnesia as a result of brain injury following meningitis in 1993. MRI scans reveal a bilateral decrease in the volume of his hippocampal region (dentate gyrus, CA1-4, subicular cortices) of approximately 45% in both the right and left hemispheres, although the volume of his perirhinal cortex appears normal. Aside from some changes to his occipital lobe and bilateral shrinkage of the amygdala, the rest of his brain appears normal on recent quantitative MRI scans. A striking feature of his memory loss is his ability to perform at normal levels on some tests of recognition, despite his consistent deficit on tests of recall. Two tests designed specifically to distinguish performance of two putative divisions of recognition memory (the Remember/Know procedure and the use of receiver operating characteristics to distinguish familiarity and recollection), provide evidence for a selective sparing of the familiarity component of recognition. The dissociation within recognition memory supports dual-process models of recognition, and also supports proposals that anatomically linked regions within the medial temporal lobe make qualitatively different contributions to recognition.
Aggleton
John P
JP
School of Psychology, Cardiff University, Tower Building, Park Place, Cardiff, Wales CF10 3AT, UK. aggleton@cf.ac.uk
Vann
Seralynne D
SD
Denby
Christine
C
Dix
Sophie
S
Mayes
Andrew R
AR
Roberts
Neil
N
Yonelinas
Andrew P
AP
D000328:Adult; D020324:Amnesia, Anterograde / Q000473:pathology* / Q000503:physiopathology*; D001930:Brain Injuries / Q000209:etiology / Q000473:pathology / Q000503:physiopathology; D016022:Case-Control Studies; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006624:Hippocampus / Q000473:pathology* / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008581:Meningitis / Q000150:complications; D011939:Mental Recall / Q000502:physiology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D012372:ROC Curve; D021641:Recognition, Psychology / Q000502:physiology*; D012189:Retrospective Studies; D015898:Tomography Scanners, X-Ray Computed