fMRI congruous word repetition effects reflect memory variability in normal elderly

NEUROBIOLOGY OF AGING

卷:31

Article

Olichney, John M.^1,2,5  Taylor, Jason R.³  Hillert, Dieter G.³  Chan, Shiao-hui^1,2  Salmon, David P.^1,2,3  Gatherwright, James⁶  Iragui, Vicente J.^1,3  Kutas, Marta^3,4 

[1] Univ Calif Davis, Ctr Mind & Brain, Davis, CA 95618 USA

[2] Univ Calif Davis, Dept Neurol, Sacramento, CA 95817 USA

[3] Univ Calif San Diego, Dept Neurosci, La Jolla, CA 92093 USA

[4] Univ Calif San Diego, Dept Cognit Sci, La Jolla, CA 92093 USA

[5] Vet Affairs San Diego Healthcare Syst, Neurol Serv, San Diego, CA 92161 USA

[6] Case Western Reserve Univ, Sch Med, Cleveland, OH 44106 USA

关键词: Aging;    Memory;    Neuroimaging;    Learning;    Semantic;    Language;    Medial temporal lobe;    Fusiform gyrus;   

DOI  :  10.1016/j.neurobiolaging.2008.10.010

来源: Elsevier

【 摘 要 】

Neural circuits mediating repetition effect for semantically congruous words on functional MRI were investigated in seventeen normal elderly (mean age = 70). Participants determined if written words were semantically congruent (50% probability) with spoken statements. Subsequent cued-recall revealed robust explicit memory only for congruous items (83% versus 8% for incongruous). Event-related BOLD responses to New > Old congruous words were found in the left > right cingulate and fusiform gyri, left parahippocampal cortex, middle and inferior frontal gyri (IFG). A group with above-median subsequent recall had markedly more widespread BOLD responses than a Low-Recall subgroup, with larger responses in the left medial temporal lobe (LMTL), IFG, and bilateral cingulate gyri. The magnitude of LMTL activation (New-Old) correlated with subsequent cued-recall, while the spatial extent of LMTL activation (New > Old) correlated with recall and recognition. Both magnitude and spatial extent of left fusiform activation correlated with subsequent recall/recognition. A neural circuit of left-hemisphere brain regions, many identified as P600 generators by invasive electrophysiological studies, was activated by New > Old congruous words, likely mediating successful verbal encoding. (C) 2008 Elsevier Inc. All rights reserved.

【 授权许可】

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