Age-Related Decreases in Interhemispheric Resting-State Functional Connectivity and Their Relationship With Executive...

Area of Science:

• Neuroscience
• Cognitive Aging
• Brain Connectivity

Background:

• Age-related brain changes are linked to cognitive decline.
• Intrinsic brain functional reorganization is a marker of cognitive aging.
• Limited understanding of age-related changes in interhemispheric functional connectivity and its relation to executive functions.

Purpose of the Study:

• To investigate age-related changes in voxel-mirrored homotopic connectivity (VMHC), a measure of interhemispheric communication.
• To examine the relationship between VMHC and executive functions in healthy adults.
• To explore the role of VMHC in mediating age-related cognitive decline.

Main Methods:

• Recruited 93 healthy volunteers aged 19-85.
• Assessed executive functions using the Delis-Kaplan Executive Function System (D-KEFS).
• Analyzed resting-state functional MRI data to compute whole-brain VMHC using multiple linear regression.

Main Results:

• Observed age-related reductions in VMHC in key brain regions: ventromedial prefrontal cortex (vmPFC), hippocampus, dorsal anterior cingulate cortex, insula, and inferior parietal lobule.
• VMHC in vmPFC and insula correlated with performance on a color-word inhibition task.
• VMHC in the inferior parietal lobule positively correlated with design fluency scores.

Conclusions:

• Age-related alterations in interhemispheric functional connectivity are evident in healthy adults.
• Reduced VMHC in specific brain networks is associated with impaired executive functions.
• Interhemispheric functional alterations represent a potential biomarker for understanding age-related cognitive decline.