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Genetic contributions to age-related decline in executive function: a 10-year longitudinal study of COMT and BDNF polymorphisms.

Erickson KI, Kim JS, Suever BL, Voss MW, Francis BM, Kramer AF - Front Hum Neurosci (2008)

Bottom Line: We found that impairments over the 10-year span on a task-switching paradigm did not vary as a function of the COMT polymorphism.However, for the BDNF polymorphism the Met carriers performed worse than Val homozygotes at the first testing session but only the Val homozygotes demonstrated a significant reduction in performance over the 10-year span.Our results argue that the COMT polymorphism does not affect the trajectory of age-related executive control decline, whereas the Val/Val polymorphism for BDNF may promote faster rates of cognitive decay in old age.

View Article: PubMed Central - PubMed

Affiliation: Psychology Department, University of Illinois at Urbana-Champaign Champaign, IL 61801, USA. kiericks@uiuc.edu

ABSTRACT
Genetic variability in the dopaminergic and neurotrophic systems could contribute to age-related impairments in executive control and memory function. In this study we examined whether genetic polymorphisms for catechol-O-methyltransferase (COMT) and brain-derived neurotrophic factor (BDNF) were related to the trajectory of cognitive decline occurring over a 10-year period in older adults. A single nucleotide polymorphism in the COMT (Val158/108Met) gene affects the concentration of dopamine in the prefrontal cortex. In addition, a Val/Met substitution in the pro-domain for BDNF (Val66Met) affects the regulated secretion and trafficking of BDNF with Met carriers showing reduced secretion and poorer cognitive function. We found that impairments over the 10-year span on a task-switching paradigm did not vary as a function of the COMT polymorphism. However, for the BDNF polymorphism the Met carriers performed worse than Val homozygotes at the first testing session but only the Val homozygotes demonstrated a significant reduction in performance over the 10-year span. Our results argue that the COMT polymorphism does not affect the trajectory of age-related executive control decline, whereas the Val/Val polymorphism for BDNF may promote faster rates of cognitive decay in old age. These results are discussed in relation to the role of BDNF in senescence and the transforming impact of the Met allele on cognitive function in old age.

No MeSH data available.


Related in: MedlinePlus

Description of the task-switching paradigm. Letter and digit stimuli were presented simultaneously in a 2 × 2 grid and participants had to switch between responding to the letters versus responding to the numbers on every 3rd trial (adapted from Rogers and Monsell, 1995).
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Figure 1: Description of the task-switching paradigm. Letter and digit stimuli were presented simultaneously in a 2 × 2 grid and participants had to switch between responding to the letters versus responding to the numbers on every 3rd trial (adapted from Rogers and Monsell, 1995).

Mentions: The task-switching paradigm examines subjects' ability to rapidly disengage from the performance of one task and switch to another. Subjects performed two different tasks that alternated after every two trials – two trials of one task followed by two trials of the other task and so on (see Figure 1). In one task subjects performed an odd/even numerical judgment (i.e., is a single digit number odd or even). In the other task subjects performed a vowel/consonant judgment. When one type of trial (e.g., digit judgment) was followed by a trial of the same type (e.g., digit judgment) it was labeled a Repeat trial. However, when participants needed to respond to a trial that was of a different task type than the previous trial, it was labeled as a Switch. Response times (RTs) to switch trials are higher than RTs to repeat trials and the accuracy rates are lower.


Genetic contributions to age-related decline in executive function: a 10-year longitudinal study of COMT and BDNF polymorphisms.

Erickson KI, Kim JS, Suever BL, Voss MW, Francis BM, Kramer AF - Front Hum Neurosci (2008)

Description of the task-switching paradigm. Letter and digit stimuli were presented simultaneously in a 2 × 2 grid and participants had to switch between responding to the letters versus responding to the numbers on every 3rd trial (adapted from Rogers and Monsell, 1995).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2572207&req=5

Figure 1: Description of the task-switching paradigm. Letter and digit stimuli were presented simultaneously in a 2 × 2 grid and participants had to switch between responding to the letters versus responding to the numbers on every 3rd trial (adapted from Rogers and Monsell, 1995).
Mentions: The task-switching paradigm examines subjects' ability to rapidly disengage from the performance of one task and switch to another. Subjects performed two different tasks that alternated after every two trials – two trials of one task followed by two trials of the other task and so on (see Figure 1). In one task subjects performed an odd/even numerical judgment (i.e., is a single digit number odd or even). In the other task subjects performed a vowel/consonant judgment. When one type of trial (e.g., digit judgment) was followed by a trial of the same type (e.g., digit judgment) it was labeled a Repeat trial. However, when participants needed to respond to a trial that was of a different task type than the previous trial, it was labeled as a Switch. Response times (RTs) to switch trials are higher than RTs to repeat trials and the accuracy rates are lower.

Bottom Line: We found that impairments over the 10-year span on a task-switching paradigm did not vary as a function of the COMT polymorphism.However, for the BDNF polymorphism the Met carriers performed worse than Val homozygotes at the first testing session but only the Val homozygotes demonstrated a significant reduction in performance over the 10-year span.Our results argue that the COMT polymorphism does not affect the trajectory of age-related executive control decline, whereas the Val/Val polymorphism for BDNF may promote faster rates of cognitive decay in old age.

View Article: PubMed Central - PubMed

Affiliation: Psychology Department, University of Illinois at Urbana-Champaign Champaign, IL 61801, USA. kiericks@uiuc.edu

ABSTRACT
Genetic variability in the dopaminergic and neurotrophic systems could contribute to age-related impairments in executive control and memory function. In this study we examined whether genetic polymorphisms for catechol-O-methyltransferase (COMT) and brain-derived neurotrophic factor (BDNF) were related to the trajectory of cognitive decline occurring over a 10-year period in older adults. A single nucleotide polymorphism in the COMT (Val158/108Met) gene affects the concentration of dopamine in the prefrontal cortex. In addition, a Val/Met substitution in the pro-domain for BDNF (Val66Met) affects the regulated secretion and trafficking of BDNF with Met carriers showing reduced secretion and poorer cognitive function. We found that impairments over the 10-year span on a task-switching paradigm did not vary as a function of the COMT polymorphism. However, for the BDNF polymorphism the Met carriers performed worse than Val homozygotes at the first testing session but only the Val homozygotes demonstrated a significant reduction in performance over the 10-year span. Our results argue that the COMT polymorphism does not affect the trajectory of age-related executive control decline, whereas the Val/Val polymorphism for BDNF may promote faster rates of cognitive decay in old age. These results are discussed in relation to the role of BDNF in senescence and the transforming impact of the Met allele on cognitive function in old age.

No MeSH data available.


Related in: MedlinePlus