title: Altered Neural Activity during Semantic Object Memory Retrieval in Amnestic Mild Cognitive Impairment as Measured by Event-Related Potentials.
abstract: Deficits in semantic memory in individuals with amnestic mild cognitive impairment (aMCI) have been previously reported, but the underlying neurobiological mechanisms remain to be clarified. We examined event-related potentials (ERPs) associated with semantic memory retrieval in 16 individuals with aMCI as compared to 17 normal controls using the Semantic Object Retrieval Task (EEG SORT). In this task, subjects judged whether pairs of words (object features) elicited retrieval of an object (retrieval trials) or not (non-retrieval trials). Behavioral findings revealed that aMCI subjects had lower accuracy scores and marginally longer reaction time compared to controls. We used a multivariate analytical technique (STAT-PCA) to investigate similarities and differences in ERPs between aMCI and control groups. STAT-PCA revealed a left fronto-temporal component starting at around 750 ms post-stimulus in both groups. However, unlike controls, aMCI subjects showed an increase in the frontal-parietal scalp potential that distinguished retrieval from non-retrieval trials between 950 and 1050 ms post-stimulus negatively correlated with the performance on the logical memory subtest of the Wechsler Memory Scale-III. Thus, individuals with aMCI were not only impaired in their behavioral performance on SORT relative to controls, but also displayed alteration in the corresponding ERPs. The altered neural activity in aMCI compared to controls suggests a more sustained and effortful search during object memory retrieval, which may be a potential marker indicating disease processes at the pre-dementia stage.
authors.affiliation: Center for BrainHealth, The University of Texas at Dallas, Dallas, TX, USA.|School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA.
authors.forename: Hsueh-Sheng
authors.initials: HS
authors.lastname: Chiang
authors.affiliation: Center for BrainHealth, The University of Texas at Dallas, Dallas, TX, USA.|School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA.|Department of Speech and Hearing Science, University of Illinois at Urbana-Champaign, Champaign, IL, USA.
authors.forename: Raksha A
authors.initials: RA
authors.lastname: Mudar
authors.affiliation: Center for BrainHealth, The University of Texas at Dallas, Dallas, TX, USA.
authors.forename: Athula
authors.initials: A
authors.lastname: Pudhiyidath
authors.affiliation: Center for BrainHealth, The University of Texas at Dallas, Dallas, TX, USA.
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Spence
authors.affiliation: Center for BrainHealth, The University of Texas at Dallas, Dallas, TX, USA.|Department of Neurology and Neurotherapeutics, The University of Texas Southwestern Medical Center, Dallas, TX, USA.|Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX, USA.
authors.forename: Kyle B
authors.initials: KB
authors.lastname: Womack
authors.affiliation: Department of Neurology and Neurotherapeutics, The University of Texas Southwestern Medical Center, Dallas, TX, USA.|Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX, USA.
authors.forename: C Munro
authors.initials: CM
authors.lastname: Cullum
authors.affiliation: The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Jeremy A
authors.initials: JA
authors.lastname: Tanner
authors.affiliation: Center for BrainHealth, The University of Texas at Dallas, Dallas, TX, USA.|School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA.
authors.forename: Justin
authors.initials: J
authors.lastname: Eroh
authors.affiliation: Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Kraut
authors.affiliation: Center for BrainHealth, The University of Texas at Dallas, Dallas, TX, USA.|School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, TX, USA.|Department of Neurology and Neurotherapeutics, The University of Texas Southwestern Medical Center, Dallas, TX, USA.|Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX, USA.
authors.forename: John
authors.initials: J
authors.lastname: Hart
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000503:physiopathology*; D060825:Cognitive Dysfunction / Q000473:pathology* / Q000503:physiopathology*; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D011939:Mental Recall / Q000502:physiology*; D008609:Mental Status Schedule; D008875:Middle Aged; D009483:Neuropsychological Tests; D025341:Principal Component Analysis; D011930:Reaction Time / Q000502:physiology; D012660:Semantics
keywords: Cognition; electroencephalography; event-related potentials; memory; mild cognitive impairment; semantics
references.citation: Can J Exp Psychol. 1999 Mar;53(1):108-17
references.pmid: 10389493
references.citation: Trends Cogn Sci. 2000 Dec 1;4(12):463-470
references.pmid: 11115760
references.citation: Psychol Aging. 2001 Mar;16(1):161-76
references.pmid: 11302364
references.citation: J Cogn Neurosci. 2002 Jan 1;14(1):24-36
references.pmid: 11798384
references.citation: Proc Natl Acad Sci U S A. 2002 Apr 30;99(9):6440-3
references.pmid: 11972063
references.citation: J Psychiatr Res. 1975 Nov;12(3):189-98
references.pmid: 1202204
references.citation: Brain Cogn. 2002 Mar-Apr;48(2-3):264-7
references.pmid: 12030448
references.citation: J Neurol Neurosurg Psychiatry. 2002 Oct;73(4):377-84
references.pmid: 12235303
references.citation: Science. 2002 Oct 25;298(5594):789-91
references.pmid: 12399581
references.citation: Neuropsychology. 2003 Apr;17(2):187-201
references.pmid: 12803424
references.citation: Psychometrika. 1965 Jun;30:179-85
references.pmid: 14306381
references.citation: J Neurosci Methods. 2004 Mar 15;134(1):9-21
references.pmid: 15102499
references.citation: Clin Neurophysiol. 2004 Oct;115(10):2195-222
references.pmid: 15351361
references.citation: J Neurosci. 2004 Nov 10;24(45):10191-200
references.pmid: 15537891
references.citation: J Am Geriatr Soc. 2005 Apr;53(4):695-9
references.pmid: 15817019
references.citation: Neuroimaging Clin N Am. 2005 Nov;15(4):869-77, xi-xii
references.pmid: 16443497
references.citation: Neuropsychologia. 2006;44(10):1928-35
references.pmid: 16616942
references.citation: Clin Neurophysiol. 2006 Jun;117(6):1319-30
references.pmid: 16644278
references.citation: Cortex. 2006 Jul;42(5):675-84
references.pmid: 16909626
references.citation: J Alzheimers Dis. 2006;9(3 Suppl):91-9
references.pmid: 16914848
references.citation: Psychiatry Res. 2006 Oct 30;147(2-3):115-26
references.pmid: 16938439
references.citation: Acta Neuropathol. 1991;81(3):261-8
references.pmid: 1711755
references.citation: Cogn Behav Neurol. 2006 Dec;19(4):177-84
references.pmid: 17159612
references.citation: Clin EEG Neurosci. 2007 Jan;38(1):8-17
references.pmid: 17319587
references.citation: Cogn Behav Neurol. 2007 Mar;20(1):62-7
references.pmid: 17356346
references.citation: Brain Lang. 2008 Jan;104(1):33-41
references.pmid: 17485107
references.citation: Neuropsychologia. 2008 Jan 31;46(2):497-510
references.pmid: 17936858
references.citation: Neurology. 2008 May 6;70(19 Pt 2):1763-70
references.pmid: 18077800
references.citation: Cortex. 2008 Jun;44(6):746-52
references.pmid: 18472044
references.citation: J Int Neuropsychol Soc. 2008 Sep;14(5):815-22
references.pmid: 18764976
references.citation: J Int Neuropsychol Soc. 2009 Jan;15(1):9-18
references.pmid: 19128524
references.citation: Neuropsychologia. 2009 Apr;47(5):1332-43
references.pmid: 19428397
references.citation: Neuropsychologia. 2010 Mar;48(4):978-88
references.pmid: 19954747
references.citation: Arch Neurol. 2009 Dec;66(12):1447-55
references.pmid: 20008648
references.citation: Neurobiol Aging. 2012 Feb;33(2):242-53
references.pmid: 20471718
references.citation: Neuropsychologia. 2010 Dec;48(14):4093-101
references.pmid: 20950632
references.citation: Alzheimers Dement. 2011 May;7(3):263-9
references.pmid: 21514250
references.citation: Prog Neurobiol. 2011 Dec;95(4):557-69
references.pmid: 21722703
references.citation: J Alzheimers Dis. 2011;26 Suppl 3:159-99
references.pmid: 21971460
references.citation: J Alzheimers Dis. 2011;26 Suppl 3:215-28
references.pmid: 21971462
references.citation: Hum Brain Mapp. 2013 Mar;34(3):651-64
references.pmid: 22102426
references.citation: J Alzheimers Dis. 2012;28(4):823-37
references.pmid: 22112550
references.citation: Int J Geriatr Psychiatry. 2012 Dec;27(12):1209-17
references.pmid: 22298328
references.citation: Brain Lang. 2013 Jul;126(1):89-98
references.pmid: 22964132
references.citation: Lancet Neurol. 2013 Feb;12(2):207-16
references.pmid: 23332364
references.citation: J Cogn Neurosci. 2013 Jun;25(6):872-86
references.pmid: 23363413
references.citation: Brain. 2013 May;136(Pt 5):1399-414
references.pmid: 23539189
references.citation: J Alzheimers Dis. 2013;36(4):711-31
references.pmid: 23666175
references.citation: Neuropsychologia. 2013 Jul;51(8):1638-48
references.pmid: 23685197
references.citation: J Alzheimers Dis. 2014;38(3):481-95
references.pmid: 24002185
references.citation: Neurology. 2013 Oct 15;81(16):1425-33
references.pmid: 24049139
references.citation: J Intern Med. 2014 Mar;275(3):214-28
references.pmid: 24605806
references.citation: Biol Psychol. 2014 Jul;100:106-14
references.pmid: 24911552
references.citation: Neuropsychologia. 1989;27(8):1073-9
references.pmid: 2797414
references.citation: J Psychiatr Res. 1982-1983;17(1):37-49
references.pmid: 7183759
references.citation: Neurology. 1993 Nov;43(11):2412-4
references.pmid: 8232972
references.citation: Electroencephalogr Clin Neurophysiol. 1996 Sep;100(5):392-406
references.pmid: 8893657
references.citation: J Int Neuropsychol Soc. 1998 Sep;4(5):415-25
references.pmid: 9745231
references.citation: J Cogn Neurosci. 1998 May;10(3):408-20
references.pmid: 9869713