Back to Search
Start Over
COMT polymorphism and memory dedifferentiation in old age.
- Source :
-
Psychology and aging [Psychol Aging] 2014 Jun; Vol. 29 (2), pp. 374-83. Date of Electronic Publication: 2013 Jul 08. - Publication Year :
- 2014
-
Abstract
- According to a neurocomputational theory of cognitive aging, senescent changes in dopaminergic modulation lead to noisier and less differentiated processing. The authors tested a corollary hypothesis of this theory, according to which genetic predispositions of individual differences in prefrontal dopamine (DA) signaling may affect associations between memory functions, particularly in old age. Latent correlations between factors of verbal episodic memory and spatial working memory were compared between individuals carrying different allelic variants of the Catechol-O-Methyltransferase (COMT) Val158Met polymorphism, which influences DA availability in prefrontal cortex. In younger adults (n = 973), correlations between memory functions did not differ significantly among the 3 COMT genotypes (r = .35); in older adults (n = 1333), however, the correlation was significantly higher in Val homozygotes (r = .70), whose prefrontal DA availability is supposedly the lowest of all groups examined, than in heterozygotes and Met homozygotes (both rs = .29). Latent means of the episodic memory and working memory factors did not differ by COMT status within age groups. However, when restricting the analysis to the low-performing tertile of older adults (n = 443), we found that Val homozygotes showed lower levels of performance in both episodic memory and working memory than heterozygotes and Met homozygotes. In line with the neurocomputational theory, the observed dedifferentiation of memory functions in older Val homozygotes suggests that suboptimal dopaminergic modulation may underlie multiple facets of memory declines during aging. Future longitudinal work needs to test this conjecture more directly.<br /> (PsycINFO Database Record (c) 2014 APA, all rights reserved.)
- Subjects :
- Adult
Aged
Catechol O-Methyltransferase chemistry
Catechol O-Methyltransferase metabolism
Dopamine metabolism
Female
Genotype
Humans
Male
Memory, Episodic
Memory, Short-Term physiology
Methionine genetics
Middle Aged
Prefrontal Cortex metabolism
Valine genetics
Young Adult
Aging genetics
Aging physiology
Catechol O-Methyltransferase genetics
Memory physiology
Polymorphism, Genetic genetics
Subjects
Details
- Language :
- English
- ISSN :
- 1939-1498
- Volume :
- 29
- Issue :
- 2
- Database :
- MEDLINE
- Journal :
- Psychology and aging
- Publication Type :
- Academic Journal
- Accession number :
- 23834492
- Full Text :
- https://doi.org/10.1037/a0033225