Open AccessA more randomly organized grey matter network is associated with deteriorating language and global cognition in individuals with subjective cognitive decline
Author(s) -
Verfaillie Sander C. J.,
Slot Rosalinde E. R.,
Dicks Ellen,
Prins Niels D.,
Overbeek Jozefien M.,
Teunissen Charlotte E.,
Scheltens Philip,
Barkhof Frederik,
van der Flier Wiesje M.,
Tijms Betty M.
Publication year - 2018
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.24065
Subject(s) - neuropsychology , cognition , psychology , grey matter , precuneus , cognitive decline , dementia , audiology , neuroscience , white matter , medicine , disease , magnetic resonance imaging , radiology
Objectives Grey matter network disruptions in Alzheimer's disease (AD) are associated with worse cognitive impairment cross‐sectionally. Our aim was to investigate whether indications of a more random network organization are associated with longitudinal decline in specific cognitive functions in individuals with subjective cognitive decline (SCD). Experimental design : We included 231 individuals with SCD who had annually repeated neuropsychological assessment (3 ± 1 years; n = 646 neuropsychological investigations) available from the Amsterdam Dementia Cohort (54% male, age: 63 ± 9, MMSE: 28 ± 2). Single‐subject grey matter networks were extracted from baseline 3D‐T1 MRI scans and we computed basic network (size, degree, connectivity density) and higher‐order (path length, clustering, betweenness centrality, normalized path length [lambda] and normalized clustering [gamma]) parameters at whole brain and/or regional levels. We tested associations of network parameters with baseline and annual cognition (memory, attention, executive functioning, language composite scores, and global cognition [all domains with MMSE]) using linear mixed models, adjusted for age, sex, education, scanner and total gray matter volume. Principal observations : Lower network size was associated with steeper decline in language (β ± SE = 0.12 ± 0.05, p < 0.05FDR). Higher‐order network parameters showed no cross‐sectional associations. Lower gamma and lambda values were associated with steeper decline in global cognition (gamma: β ± SE = 0.06 ± 0.02); lambda: β ± SE = 0.06 ± 0.02), language (gamma: β ± SE = 0.11 ± 0.04; lambda: β ± SE = 0.12 ± 0.05; all p < 0.05FDR). Lower path length values in precuneus and fronto‐temporo‐occipital cortices were associated with a steeper decline in global cognition. Conclusions A more randomly organized grey matter network was associated with a steeper decline of cognitive functioning, possibly indicating the start of cognitive impairment.