Assessment of EEG dynamical complexity in Alzheimer's disease using multiscale entropy.
OBJECTIVE
Multiscale entropy (MSE) is a recently proposed entropy-based index of physiological complexity, evaluating signals at multiple temporal scales. To test this method as an aid to elucidating the pathophysiology of Alzheimer's disease (AD), we examined MSE in resting state EEG activity in comparison with traditional EEG analysis.


METHODS
We recorded EEG in medication-free 15 presenile AD patients and 18 age- and sex-matched healthy control (HC) subjects. MSE was calculated for continuous 60-s epochs for each group, concurrently with power analysis.


RESULTS
The MSE results from smaller and larger scales were associated with higher and lower frequencies of relative power, respectively. Group analysis demonstrated that the AD group had less complexity at smaller scales in more frontal areas, consistent with previous findings. In contrast, higher complexity at larger scales was observed across brain areas in AD group and this higher complexity was significantly correlated with cognitive decline.


CONCLUSIONS
MSE measures identified an abnormal complexity profile across different temporal scales and their relation to the severity of AD.


CONCLUSIONS
These findings indicate that entropy-based analytic methods with applied at temporal scales may serve as a complementary approach for characterizing and understanding abnormal cortical dynamics in AD.
Mizuno
Tomoyuki
T
Department of Neuropsychiatry, Faculty of Medical Sciences, University of Fukui, Fukui, Japan.
Takahashi
Tetsuya
T
Department of Neuropsychiatry, Faculty of Medical Sciences, University of Fukui, Fukui, Japan; Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA. Electronic address: takahash@u-fukui.ac.jp.
Cho
Raymond Y
RY
Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA.
Kikuchi
Mitsuru
M
Department of Psychiatry and Neurobiology, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan.
Murata
Tetsuhito
T
Department of Neuropsychiatry, Faculty of Medical Sciences, University of Fukui, Fukui, Japan.
Takahashi
Koichi
K
Department of Informatics, Faculty of Science and Engineering, Kinki University, Higashi-Osaka, Japan.
Wada
Yuji
Y
Department of Neuropsychiatry, Faculty of Medical Sciences, University of Fukui, Fukui, Japan.
D000368:Aged; D000544:Alzheimer Disease / Q000503:physiopathology*; D000704:Analysis of Variance; D016022:Case-Control Studies; D004569:Electroencephalography / Q000379:methods; D019277:Entropy; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D017711:Nonlinear Dynamics; D013223:Statistics as Topic
Clin Neurophysiol. 2009 Mar;120(3):476-83
19231279
Alzheimers Dement. 2008 Nov;4(6):381-9
19012862
Behav Brain Res. 2000 Nov;115(2):235-49
11000423
Hosp Community Psychiatry. 1986 Dec;37(12):1199-201
3804220
Proc Natl Acad Sci U S A. 1994 May 24;91(11):5033-7
8197179
Trends Cogn Sci. 1998 Dec 1;2(12):474-84
21227298
Int J Psychophysiol. 2008 Apr;68(1):75-80
18093675
Neurology. 1984 Jul;34(7):939-44
6610841
Clin Neurophysiol. 2003 Jun;114(6):1034-40
12804672
Neurobiol Aging. 2002 Jan-Feb;23(1):23-6
11755014
Br Med Bull. 1996 Jul;52(3):644-55
8949263
Annu Int Conf IEEE Eng Med Biol Soc. 2007;2007:6192-5
18003435
Acta Neurobiol Exp (Wars). 2000;60(1):87-108
10769933
Neuroimage. 2010 May 15;51(1):173-82
20149880
Clin Neurophysiol. 2005 Oct;116(10):2266-301
16115797
J Psychiatr Res. 1975 Nov;12(3):189-98
1202204
Am J Physiol Heart Circ Physiol. 2000 Jun;278(6):H2039-49
10843903
Clin Neurophysiol. 2008 Apr;119(4):837-41
18258479
Phys Rev E Stat Nonlin Soft Matter Phys. 2005 Feb;71(2 Pt 1):021906
15783351
Clin Neurophysiol. 2001 May;112(5):827-35
11336898
Neural Netw. 2000 Oct-Nov;13(8-9):909-22
11156201
Clin Electroencephalogr. 1996 Apr;27(2):84-8
8681467
Physiol Meas. 2006 Mar;27(3):241-53
16462011
Proc Natl Acad Sci U S A. 1991 Mar 15;88(6):2297-301
11607165
Clin Neurophysiol. 2005 Aug;116(8):1826-34
15979403
Clin Neurophysiol. 2004 Jul;115(7):1490-505
15203050
Physiol Meas. 2006 Nov;27(11):1091-106
17028404
Neuropsychol Rev. 2003 Jun;13(2):79-92
12887040
Neurosci Biobehav Rev. 2007;31(7):1003-16
17532471
Phys Rev Lett. 2002 Aug 5;89(6):068102
12190613
Acta Neurol Scand. 2003 Aug;108(2):90-6
12859284