title: Impaired capacity for familiarity after hippocampal damage.
abstract: Recognition memory is thought to consist of two components: recollection and familiarity. Whereas it is widely agreed that the hippocampus supports recollection (remembering the episode in which an item was learned), there is uncertainty about whether it also supports familiarity (simply knowing that an item was encountered but without remembering the learning episode). We tested a counterintuitive prediction that follows from the idea that the hippocampus selectively supports recollection. Patients with hippocampal lesions should have strong experiences of familiarity as often as controls do; however, unlike controls, these experiences should not be accompanied by recollection. Accordingly, with methods that allow participants to report whether they remember an item as encountered previously or whether they simply know it is familiar, patients should express strong familiarity (in the absence of recollection) more often than controls. We indexed strong familiarity and recollection for previously studied words by obtaining confidence ratings together with Remember-Know judgments. The result was that patients provided fewer high-confidence Know responses than controls rather than more. Furthermore, the number of Know responses made by patients was substantially less than was predicted if recollection were impaired. This was true regardless of whether the prediction was based on the assumption that recollection and familiarity are independent or dependent processes. These results suggest that hippocampal lesions impair both recollection and familiarity. Unlike many previous studies of these constructs, the prediction (and the result) is independent of any particular theoretical model, and it holds even if Remember-Know judgments are not process-pure indicators of recollection and familiarity.
authors: Veterans Affairs Medical Center, San Diego, CA 92161, USA.
authors: Zhuang
authors: Z
authors: Song
authors: John T
authors: JT
authors: Wixted
authors: Ramona O
authors: RO
authors: Hopkins
authors: Larry R
authors: LR
authors: Squire
references: Psychol Rev. 2008 Apr;115(2):426-46
references: 18426296
references: Psychol Rev. 2010 Oct;117(4):1025-54
references: 20836613
references: Hippocampus. 2008;18(5):469-80
references: 18306303
references: Hippocampus. 2005;15(1):79-85
references: 15390163
references: Psychol Rev. 2004 Apr;111(2):524-42
references: 15065921
references: Psychon Bull Rev. 2004 Aug;11(4):616-41
references: 15581116
references: Proc Natl Acad Sci U S A. 2010 Jan 5;107(1):344-8
references: 19966306
references: Hippocampus. 2005;15(2):203-15
references: 15390152
references: Neuron. 2003 Jan 9;37(1):171-80
references: 12526782
references: Nat Rev Neurosci. 2007 Nov;8(11):872-83
references: 17948032
references: J Exp Psychol Learn Mem Cogn. 1996 Mar;22(2):365-77
references: 8901341
references: J Neurosci. 2006 Dec 20;26(51):13311-7
references: 17182781
references: Annu Rev Neurosci. 2007;30:123-52
references: 17417939
references: J Exp Psychol Gen. 2001 Sep;130(3):361-79
references: 11561915
references: J Int Neuropsychol Soc. 2008 May;14(3):365-72
references: 18419835
references: Neuropsychologia. 2005;43(12):1810-23
references: 16154457
references: Proc Natl Acad Sci U S A. 2010 Nov 2;107(44):19044-8
references: 20956323
references: Nat Rev Neurosci. 2001 Jan;2(1):51-61
references: 11253359
references: J Exp Psychol Learn Mem Cogn. 1994 Nov;20(6):1341-54
references: 7983467
references: J Exp Psychol Learn Mem Cogn. 1995 May;21(3):699-710
references: 7602267
references: Trends Cogn Sci. 2011 May;15(5):210-7
references: 21481629
references: Nat Neurosci. 2002 Nov;5(11):1236-41
references: 12379865
references: J Neurosci. 1996 Aug 15;16(16):5233-55
references: 8756452