Open AccessThe APOE ɛ4 allele affects complexity and functional connectivity of resting brain activity in healthy adults
Author(s) -
Yang Albert C.,
Huang ChuChung,
Liu MuEn,
Liou YinJay,
Hong ChenJee,
Lo MenTzung,
Huang Norden E.,
Peng ChungKang,
Lin ChingPo,
Tsai ShihJen
Publication year - 2014
Publication title -
human brain mapping
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.005
H-Index - 191
eISSN - 1097-0193
pISSN - 1065-9471
DOI - 10.1002/hbm.22398
Subject(s) - precuneus , apolipoprotein e , posterior cingulate , resting state fmri , psychology , functional magnetic resonance imaging , default mode network , neuroscience , medicine , disease
The apolipoprotein E (APOE) gene is associated with structural and functional brain changes. We have used multiscale entropy (MSE) analysis to detect changes in the complexity of resting blood oxygen level‐dependent (BOLD) signals associated with aging and cognitive function. In this study, we further hypothesized that the APOE genotype may affect the complexity of spontaneous BOLD activity in younger and older adults, and such altered complexity may be associated with certain changes in functional connectivity. We conducted a resting‐state functional magnetic resonance imaging experiment in a cohort of 100 younger adults (aged 20–39 years; mean 27.2 ± 4.3 years; male/female: 53/47) and 112 older adults (aged 60–79 years; mean 68.4 ± 6.5 years; male/female: 54/58), and applied voxelwise MSE analysis to assess the main effect of APOE genotype on resting‐state BOLD complexity and connectivity. Although the main effect of APOE genotype on BOLD complexity was not observed in younger group, we observed that older APOE ɛ4 allele carriers had significant reductions in BOLD complexity in precuneus and posterior cingulate regions, relative to noncarriers. We also observed that reduced BOLD complexity in precuneus and posterior cingulate regions was associated with increased functional connectivity to the superior and inferior frontal gyrus in the older group. These results support the compensatory recruitment hypothesis in older APOE ɛ4 carriers, and confer the impact of the APOE genotype on the temporal dynamics of brain activity in older adults. Hum Brain Mapp 35:3238–3248, 2014 . © 2013 Wiley Periodicals, Inc .