Frontal connections and cognitive changes in normal aging rhesus monkeys: a DTI study
Nikos Makris1, George M Papadimitriou, Andre van der Kouwe
1Harvard Medical School Department of Neurology, Center for Morphometric Analysis, Massachusetts General Hospital, Boston, MA 02129, United States. nikos@cma.mgh.harvard.edu
Neurobiology of Aging
|September 12, 2006
Summary
Aging brains show white matter damage, particularly in long fiber tracts. This impacts communication and executive function, leading to cognitive decline in normal aging.
Area of Science:
- Neuroscience
- Aging Research
Background:
- Cortical neurons are preserved during aging, but myelin and axons degrade.
- White matter integrity is crucial for cognitive function.
Purpose of the Study:
- To investigate age-related white matter changes in rhesus monkeys.
- To test if these changes affect long corticocortical association fiber tracts.
- To correlate white matter integrity with cognitive performance.
Main Methods:
- Diffusion tensor imaging (DT-MRI) was used to analyze brain data.
- Fractional anisotropy (FA) maps were created for young and elderly monkeys.
- Behavioral tests assessed executive function.
Main Results:
- Significant reductions in FA were observed in the superior longitudinal fasciculus II, cingulum bundle, and anterior corpus callosum.
- FA reductions correlated linearly with executive function performance.
Conclusions:
- Age-related white matter alterations in specific fiber tracts contribute to cognitive impairments.
- This study provides novel insights into aging-related cognitive decline in non-human primates.
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