TY - JOUR
T1 - Cognition in healthy aging is related to regional white matter integrity, but not cortical thickness
AU - Ziegler, David A.
AU - Piguet, Olivier
AU - Salat, David H.
AU - Prince, Keyma
AU - Connally, Emily
AU - Corkin, Suzanne
PY - 2010/11
Y1 - 2010/11
N2 - It is well established that healthy aging is accompanied by structural changes in many brain regions and functional decline in a number of cognitive domains. The goal of this study was to determine (1) whether the regional distribution of age-related brain changes is similar in gray matter (GM) and white matter (WM) regions, or whether these two tissue types are affected differently by aging, and (2) whether measures of cognitive performance are more closely linked to alterations in the cerebral cortex or in the underlying WM in older adults (OA). To address these questions, we collected high-resolution magnetic resonance imaging (MRI) data from a large sample of healthy young adults (YA; aged 18-28) and OA (aged 61-86 years). In addition, the OA completed a series of tasks selected to assess cognition in three domains: cognitive control, episodic memory, and semantic memory. Using advanced techniques for measuring cortical thickness and WM integrity, we found that healthy aging was accompanied by deterioration of both GM and WM, but with distinct patterns of change: Cortical thinning occurred primarily in primary sensory and motor cortices, whereas WM changes were localized to regions underlying association cortices. Further, in OA, we found a striking pattern of region-specific correlations between measures of cognitive performance and WM integrity, but not cortical thickness. Specifically, cognitive control correlated with integrity of frontal lobe WM, whereas episodic memory was related to integrity of temporal and parietal lobe WM. Thus, age-related impairments in specific cognitive capacities may arise from degenerative processes that affect the underlying connections of their respective neural networks.
AB - It is well established that healthy aging is accompanied by structural changes in many brain regions and functional decline in a number of cognitive domains. The goal of this study was to determine (1) whether the regional distribution of age-related brain changes is similar in gray matter (GM) and white matter (WM) regions, or whether these two tissue types are affected differently by aging, and (2) whether measures of cognitive performance are more closely linked to alterations in the cerebral cortex or in the underlying WM in older adults (OA). To address these questions, we collected high-resolution magnetic resonance imaging (MRI) data from a large sample of healthy young adults (YA; aged 18-28) and OA (aged 61-86 years). In addition, the OA completed a series of tasks selected to assess cognition in three domains: cognitive control, episodic memory, and semantic memory. Using advanced techniques for measuring cortical thickness and WM integrity, we found that healthy aging was accompanied by deterioration of both GM and WM, but with distinct patterns of change: Cortical thinning occurred primarily in primary sensory and motor cortices, whereas WM changes were localized to regions underlying association cortices. Further, in OA, we found a striking pattern of region-specific correlations between measures of cognitive performance and WM integrity, but not cortical thickness. Specifically, cognitive control correlated with integrity of frontal lobe WM, whereas episodic memory was related to integrity of temporal and parietal lobe WM. Thus, age-related impairments in specific cognitive capacities may arise from degenerative processes that affect the underlying connections of their respective neural networks.
KW - Aging
KW - Cognitive control processes
KW - Cortical thickness
KW - DTI
KW - Episodic memory
KW - MRI
KW - White matter
UR - http://www.scopus.com/inward/record.url?scp=77956945637&partnerID=8YFLogxK
U2 - 10.1016/j.neurobiolaging.2008.10.015
DO - 10.1016/j.neurobiolaging.2008.10.015
M3 - Article
C2 - 19091444
AN - SCOPUS:77956945637
VL - 31
SP - 1912
EP - 1926
JO - Neurobiology of Aging
JF - Neurobiology of Aging
SN - 0197-4580
IS - 11
ER -