Increased parasympathetic activity and ability to generate positive emotion: The influence of the BDNF Val66Met polymorphism on emotion flexibility.

Cross-species behavioral research suggests that a single nucleotide polymorphism (SNP) in the brain-derived neurotrophic factor (BDNF) gene (rs6265, Val66Met), influences behavioral inflexibility. This SNP has not yet been linked to variability in emotion-related behaviors, despite broader evidence suggesting an association may be present. This investigation explored the role of the BDNF Val66Met polymorphism in emotion response behaviors measured during a lab-based emotional provocation. Specifically, the influence of BDNF Val66Met in emotion flexibility was explored in a sample of healthy adults (N = 120), emotion responses were recorded during the emotional provocation on multiple dimensions, in response to emotionally-evocative videos of negative then positive valence. These results suggest that Met carriers exhibit decreased parasympathetic responding, and reduced ability to generate positive emotion, relative to Val homozygotes. These findings are the first to suggest an association between the Met allele and a pattern of responding indicative of emotion inflexibility that might afford greater risk for psychopathology. [ABSTRACT FROM AUTHOR]