Age- and function-related regional changes in cortical folding of the default mode network in older adults

Abstract

Healthy aging is accompanied by changes in the functional architecture of the default mode network (DMN), e.g. a posterior to anterior shift (PASA) of activations. The putative structural correlate for this functional reorganization, however, is largely unknown. Changes in gyrification, i.e. decreases of cortical folding were found to be a marker of atrophy of the brain in later decades of life. Therefore, the present study assessed local gyrification indices of the DMN in relation to age and cognitive performance in 749 older adults aged 55-85 years. Age-related decreases in local gyrification indices were found in the anterior part of the DMN [particularly; medial prefrontal cortex (mPFC)] of the right hemisphere, and the medial posterior parts of the DMN [particularly; posterior cingulate cortex (PCC)/precuneus] of both hemispheres. Positive correlations between cognitive performance and local gyrification indices were found for (1) selective attention and left PCC/precuneus, (2) visual/visual-spatial working memory and bilateral PCC/precuneus and right angular gyrus (AG), and (3) semantic verbal fluency and right AG and right mPFC. The more pronounced age-related decrease in local gyrification indices of the posterior parts of the DMN supports the functionally motivated PASA theory by correlated structural changes. Surprisingly, the prominent age-related decrease in local gyrification indices in right hemispheric ROIs provides evidence for a structural underpinning of the right hemi-aging hypothesis. Noticeably, the performance-related changes in local gyrification largely involved the same parts of the DMN that were subject to age-related local gyrification decreases. Thus, the present study lends support for a combined structural and functional theory of aging, in that the functional changes in the DMN during aging are accompanied by comparably localized structural alterations.

Generalizing age effects on brain structure and cognition: A two‐study comparison approach

“…Beyond assessing mean CT for the two hemispheres, we also analyzed age‐related differences in regional CT (different parts of the DMN). The choice of regions of interest was based on an earlier study of Jockwitz et al (). Herein, the authors aimed at assessing structural correlates for functionally established theories of the aging brain.…”

“…In addition, CT was determined for six regions of interest belonging to the DMN, a bilateral network composed of the medial prefrontal cortex (anterior DMN), the posterior cingulate cortex/precuneus (medial posterior DMN) as well as the inferior parietal lobule (lateral posterior DMN). Those regions have been defined for the purpose of a previous study and are described in detail by Jockwitz et al (). In short, functional resting state scans from 691 subjects in 1000BRAINS were preprocessed using the preprocessing pipeline provided by the FSL software package 5.0 (including denoising strategies: FIX; Griffanti et al (); Salimi‐Khorshidi et al ()).…”

“…As we get older, our brain undergoes substantial structural changes that seem to be related to changes in behavior (i.e., cognitive decline in older adults). However, previous research has shown that it is far from simple to bring the two domains—namely brain structure and behavior—together (Fjell et al, ; Jockwitz et al, ; Liu et al, ; Raz & Rodrigue, ; Ziegler, Dahnke, Gaser, & Alzheimer's Disease Neuroimaging, ). One important reason for this is that age‐related changes in both domains are complex and insufficiently understood.…”

Network‐based decoupling of local gyrification in obsessive‐compulsive disorder

“…Further evidence also indicates a potential relationship between structural connectivity and cortical folding (Takahashi, Folkerth, Galaburda, & Grant, ; Van Essen, ). Additionally, several studies have revealed a structure‐cognition relationship in healthy subjects in terms of associations between local gyrification and cognitive performance in working memory and mental flexibility tasks (Gautam, Anstey, Wen, Sachdev, & Cherbuin, ) as well as attention and semantic verbal fluency tasks (Jockwitz et al, ). Interestingly, gyrification has been demonstrated to mainly occur between the last two trimesters of gestation up to approximately one year (Armstrong, Schleicher, Omran, Curtis, & Zilles, ; White et al, ), thus making it a potential marker for early neurodevelopment.…”

577. Lifespan Gyrification Trajectories of Human Brain in Healthy Individuals and Patients with Major Psychiatric Disorders

“…1). The GI increases with brain mass across species 3 , and GI decreases during healthy aging in humans 4,5 . The trajectory of brain cortical gyrification from childhood to old age in human is still unknown.…”