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Elevated Dopamine Synthesis as a Mechanism of Cognitive Resilience in Aging.

ABSTRACT: Aging is associated with declines in multiple components of the dopamine system including loss of dopamine-producing neurons, atrophy of the dopamine system's cortical targets, and reductions in the density of dopamine receptors. Countering these patterns, dopamine synthesis appears to be stable or elevated in older age. We tested the hypothesis that elevation in dopamine synthesis in aging reflects a compensatory response to neuronal loss rather than a nonspecific monotonic shift in older age. We measured individual differences in striatal dopamine synthesis capacity in cognitively normal older adults using [18F]Fluoro-l-m-tyrosine positron emission tomography cross-sectionally and tested relationships with longitudinal reductions in cortical thickness and working memory decline beginning up to 13 years earlier. Consistent with a compensation account, older adults with the highest dopamine synthesis capacity were those with greatest atrophy in posterior parietal cortex. Elevated dopamine synthesis capacity was not associated with successful maintenance of working memory performance overall, but had a moderating effect such that higher levels of dopamine synthesis capacity reduced the impact of atrophy on cognitive decline. Together, these findings support a model by which upregulation of dopamine synthesis represents a mechanism of cognitive resilience in aging.

SUBMITTER: Ciampa CJ

PROVIDER: S-EPMC9247426 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Elevated Dopamine Synthesis as a Mechanism of Cognitive Resilience in Aging.

Ciampa Claire J CJ Parent Jourdan H JH Lapoint Molly R MR Swinnerton Kaitlin N KN Taylor Morgan M MM Tennant Victoria R VR Whitman A J AJ Jagust William J WJ Berry Anne S AS

Cerebral cortex (New York, N.Y. : 1991) 20220601 13

Aging is associated with declines in multiple components of the dopamine system including loss of dopamine-producing neurons, atrophy of the dopamine system's cortical targets, and reductions in the density of dopamine receptors. Countering these patterns, dopamine synthesis appears to be stable or elevated in older age. We tested the hypothesis that elevation in dopamine synthesis in aging reflects a compensatory response to neuronal loss rather than a nonspecific monotonic shift in older age. ...[more]

PMID: 34718454

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Elevated Dopamine Synthesis as a Mechanism of Cognitive Resilience in Aging.

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Elevated Dopamine Synthesis as a Mechanism of Cognitive Resilience in Aging.

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