The COMT gene modulates the relationship between bilingual adaptation in executive function and decision-making: an...

Area of Science:

• Neuroscience
• Genetics
• Cognitive Psychology

Background:

• Bilingualism is associated with enhanced executive functions, potentially linked to genetic factors like dopamine (DA) genes.
• The interplay between innate genetic predispositions and acquired cognitive training in bilinguals remains unclear regarding executive advantages.
• Investigating the catecholamine-O-methyltransferase (COMT) gene's role in executive control and decision-making is crucial.

Purpose of the Study:

• To examine the relationship between COMT gene polymorphism, executive control, and decision-making in Chinese-English bilinguals.
• To determine if COMT genotype influences performance on language switching and decision-making tasks.
• To explore how genetic factors modulate the generalized executive advantages observed in bilingual individuals.

Main Methods:

• Recruited 101 Chinese-English bilingual participants.
• Administered a language switching task to assess executive control.
• Utilized the Iowa Gambling Task (IGT) to evaluate decision-making.
• Genotyped participants for the COMT Val158Met polymorphism using electroencephalography (EEG).

Main Results:

• COMT Val158Met polymorphism significantly impacted both decision-making and executive control.
• Valine (Val) homozygotes showed poorer performance on the IGT, indicating less optimal decision-making.
• Methionine (Met) carriers exhibited larger switch costs in the language switching task.
• A significant interaction was found: Met allele carriers demonstrated both larger switch costs and better IGT performance.

Conclusions:

• The COMT Val158Met genotype plays a complex role in bilingual executive functions and decision-making.
• Bilinguals carrying the Met allele possess more efficient adaptive executive function mechanisms.
• These enhanced mechanisms appear to generalize beyond language control to other cognitive domains like decision-making.