Olfaction in aging and Alzheimer's disease: event-related potentials to a cross-modal odor-recognition memory task discriminate ApoE epsilon4+ and ApoE epsilon 4- individuals.
Alzheimer's disease (AD) is a devastating neurodegenerative condition that affects more than 5 million Americans. Currently, a definitive and unequivocal diagnosis of AD can only be confirmed histopathogically via postmortem autopsy, demonstrating the need for objective measures of cognitive functioning for those at risk for AD. The single most important genetic risk factor of AD is the apolipoprotein E (ApoE) epsilon4 allele. The present study investigated olfactory and cognitive processing deficits in ApoE epsilon4(+) individuals using a cross-modal recognition memory task and an objective electrophysiological measure, the event-related potential (ERP). Ten epsilon4(+) individuals (5 M, 5 F, mean [M]= 75.1 years) and 10 age- and gender-matched epsilon4(-) individuals (5 M, 5 F, M = 71 years) sequentially encoded a set of 16 olfactory stimuli and were subsequently shown names of odors previously presented (targets) or not (foils). EEG activity was recorded from 19 electrodes as participants distinguished targets from foils using a two-button mouse. P3 latencies were significantly longer in epsilon4(+) individuals, and intraclass correlations demonstrated differential activity between the two groups. These findings are consistent with a compensatory hypothesis, which posits that nondemented epsilon4(+) individuals will expend greater effort in cognitive processing or engage in alternative strategies and therefore require greater activation of neural tissue or recruitment of different neural populations. The findings also suggest that cross-modal ERP studies of recognition memory discriminate early neurocognitive changes in ApoE epsilon4(+) and ApoE epsilon4(-) individuals and may contribute to identifying the phenotype of persons who will develop Alzheimer's disease.
Murphy
Claire
C
San Diego State University, San Diego, California 92120-4913, USA. cmurphy@sciences.sdsu.edu
Solomon
Ethan S
ES
Haase
Lori
L
Wang
Miran
M
Morgan
Charlie D
CD
D000368:Aged; D000544:Alzheimer Disease / Q000235:genetics / Q000503:physiopathology*; D053327:Apolipoprotein E4 / Q000235:genetics / Q000502:physiology*; D005071:Evoked Potentials; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory; D055696:Olfactory Perception; D012307:Risk Factors; D012903:Smell
D053327:Apolipoprotein E4
Ann Neurol. 1985 Mar;17(3):278-82
3158266
J Clin Exp Neuropsychol. 2003 Aug;25(5):671-9
12815504
Neurobiol Aging. 1991 Jul-Aug;12(4):295-312
1961359
Neurology. 1995 Dec;45(12):2203-6
8848194
Neurology. 1998 Jan;50(1):169-74
9443475
J Clin Exp Neuropsychol. 1999 Feb;21(1):108-26
10421006
Neuroimage. 2006 Feb 1;29(3):853-8
16154767
Arch Neurol. 1999 Nov;56(11):1398-403
10555661
Neurology. 1999 Nov 10;53(8):1825-32
10563634
Neurobiol Aging. 2004 May-Jun;25(5):641-50
15172743
J Psychiatr Res. 1975 Nov;12(3):189-98
1202204
Biol Psychol. 1988 Jun;26(1-3):231-67
3207785
JAMA. 1997 Oct 22-29;278(16):1349-56
9343467
Ann N Y Acad Sci. 1998 Nov 30;855:744-50
9929680
Lancet. 1993 Sep 18;342(8873):697-9
8103819
J Gerontol B Psychol Sci Soc Sci. 2000 Mar;55(2):S69-75
10794191
J Biol Chem. 1985 May 25;260(10):6240-7
3922972
Trends Neurosci. 1994 Dec;17(12):525-30
7532337
J Neurosci. 2000 Oct 15;20(20):7776-81
11027241
Acta Neuropathol. 1989;77(5):535-46
2524150
JAMA. 2002 Nov 13;288(18):2307-12
12425708
Acta Neurol Scand. 1999 Jul;100(1):53-60
10416512
Psychophysiology. 1986 Nov;23(6):695-703
3823345
Ann N Y Acad Sci. 1998 Nov 30;855:723-31
9929677
J Am Geriatr Soc. 1998 Dec;46(12):1493-8
9848808
J Clin Exp Neuropsychol. 1995 Oct;17(5):793-803
8557819
Psychophysiology. 1999 May;36(3):281-7
10352551
Science. 1983 Sep 9;221(4615):1080-2
6879207
Arch Neurol. 2003 Aug;60(8):1119-22
12925369
Arch Neurol. 1997 Sep;54(9):1110-4
9311354
Lancet. 1993 Sep 18;342(8873):710-1
8103823
J Neurol Neurosurg Psychiatry. 1984 Jan;47(1):56-60
6693914
Neurology. 1991 May;41(5 Suppl 2):77-80; discussion 80-1
2041598
Neuroscience. 1995 Jul;67(1):65-72
7477910
Neurobiol Aging. 2001 May-Jun;22(3):439-47
11378251
Neurosci Lett. 1996 Feb 9;204(3):177-80
8938259
Exp Gerontol. 2004 Mar;39(3):433-41
15036403
BMJ. 1994 Nov 5;309(6963):1202-6
7987151
J Int Neuropsychol Soc. 2002 Sep;8(6):753-63
12240739
Ann N Y Acad Sci. 1998 Nov 30;855:686-93
9929672
Curr Opin Neurol. 2004 Dec;17(6):719-23
15542981
Neuropsychology. 1997 Jan;11(1):126-37
9055276
Am J Geriatr Psychiatry. 2007 Oct;15(10):869-78
17911364
JAMA. 1995 Feb 1;273(5):373-4
7823376
Electroencephalogr Clin Neurophysiol. 1997 Jul;104(4):351-8
9246073
Ann Neurol. 1996 Jul;40(1):55-66
8687193
J Clin Neurophysiol. 1998 Jan;15(1):14-33
9502510
Psychol Aging. 1998 Mar;13(1):80-7
9533192
J Neurol Neurosurg Psychiatry. 2002 Jun;72(6):820
12023438
Neurobiol Aging. 2002 May-Jun;23(3):397-404
11959402
Int J Psychophysiol. 2000 May;36(2):133-45
10742568
J Gerontol A Biol Sci Med Sci. 2000 Feb;55(2):M103-9
10737693
Neuroimage. 2006 May 15;31(1):386-96
16414279
Trends Neurosci. 1996 Jun;19(6):224-8
8761956
Neurobiol Aging. 1990 Jul-Aug;11(4):465-9
2381506
Hum Genet. 1982;62(3):233-6
7169215
Proc Natl Acad Sci U S A. 1993 Mar 1;90(5):1977-81
8446617
Chem Senses. 1994 Feb;19(1):47-56
8055258
Ann Otol Rhinol Laryngol. 1998 May;107(5 Pt 1):421-6
9596222
Int Psychogeriatr. 1997;9 Suppl 1:257-61; discussion 269-72
9447446
Dementia. 1996 May-Jun;7(3):169-74
8740632
J Clin Exp Neuropsychol. 2004 Sep;26(6):779-94
15370375
Hum Brain Mapp. 2004 Aug;22(4):280-9
15202106
Brain Res. 1991 Feb 8;541(1):163-6
2029618
JAMA. 1999 Jul 7;282(1):40-6
10404910
Neuroreport. 2002 Jan 21;13(1):149-52
11924877
Lancet. 1995 Nov 25;346(8987):1387-90
7475820
Prog Neuropsychopharmacol Biol Psychiatry. 1986;10(3-5):579-86
3541051
Ann Neurol. 1995 Nov;38(5):797-808
7486872
J Clin Exp Neuropsychol. 1999 Jun;21(3):341-51
10474173
Arch Neurol. 1998 Aug;55(8):1065-9
9708956
Brain Cogn. 2005 Jul;58(2):178-82
15919549
Annu Rev Neurosci. 2003;26:81-104
12574495