Preliminary investigation of the influence of dopamine regulating genes on social working memory

Abstract

Working memory (WM) refers to mental processes that enable temporary retention and manipulation of information, including information about other people (“social working memory”). Previous studies have demonstrated that nonsocial WM is supported by dopamine neurotransmission. Here, we investigated in 131 healthy adults whether dopamine is similarly involved in social WM by testing whether social and nonsocial WM are influenced by genetic variants in three genes coding for molecules regulating the availability of dopamine in the brain: catechol-O-methyltransferase (COMT), dopamine active transporter (DAT), and monoamine-oxidase A (MAOA). An advantage for the Met allele of COMT was observed in the two standard WM tasks and in the social WM task. However, the influence of COMT on social WM performance was not accounted for by its influence on either standard WM paradigms. There was no main effect of DAT1 or MAOA, but a significant COMT × DAT1 interaction on social WM performance. This study provides novel preliminary evidence of effects of genetic variants of the dopamine neurotransmitter system on social cognition. The results further suggest that the effects observed on standard WM do not explain the genetic effects on effortful social cognition.

Mesocorticolimbic dopamine functioning in primary psychopathy: A source of within-group heterogeneity

“…In line with these findings, Val-homozygosity strongly modulated the pathway from ADHD to extreme antisocial behavior through the endophenotype of impaired social cognition in a large group of children aged around 7 years (N=4.365) and was associated with worse performance on social WM tasks compared to Methomozygotes (Langley et al, 2010;Dumontheil et al, 2014). In addition, Val-homozygotes performed worse on different aspects of social cognition such as openness to feelings and the ability to modulate feelings in oneself and others so as to promote personal understanding and growth (Lin et al, 2013).…”

Development of dopaminergic genetic associations with visuospatial, verbal and social working memory

“…There was a main effect of age group (Table ), with faster RTs in adults (1,840 ms ± 34) than adolescents (2,085 ms ± 31), and a significant interaction between age group and genotype (Table ). Similar to visuospatial WM, analysis of simple effects indicated that the effect of genotype was significant in adults ( F (1,302) = 7.12, p = .008, η p 2 = 0.023, see Dumontheil et al, ), with faster RTs in Met/Met individuals than Val carriers, but not in adolescents ( F (1,302) = 1.30, p = .255), where the pattern was in the opposite direction (Figure c). Simple effects analyses also indicated that the difference in social WM RT between Met/Met adults and Met/Met adolescents was greater ( F (1,302) = 22.10, p < .001, η p 2 = 0.068), than between adult and adolescent Val carriers ( F (1,302) = 6.60, p = .011, η p 2 = 0.021; Figure c), a pattern similar to that observed in the visuospatial WM task.…”

“…The predicted interaction between age group and genotype was significant (Table ). Simple effects analysis, indicated that the simple main effect of genotype was significant in adults ( F (1,324) = 8.95, p = .003, η p 2 = 0.027, see Dumontheil et al, ), with better performance in Met/Met individuals than Val carriers, but not in adolescents ( F (1,324) = 2.64, p = .106) where the direction of effects was in the opposite direction (Figure b). Analysis of the simple main effect of Age group indicated that Met/Met adults had higher visuospatial WM scores than Met/Met adolescents ( F (1,324) = 20.14, p < .001, η p 2 = 0.059), while Val carriers adults and Val carriers adolescents did not differ ( F (1,324) = 1.04, p = 0.308).…”

“…Univariate ANOVAs were performed to investigate the effects of genotype (Met/Met, Val carriers) and age group (children and adolescents, adults) on task performance. Analyses were limited to the three measures which showed associations with COMT genotype in the adult sample (Dumontheil et al, ) to reduce the number of tests performed. Thus, the dependent variables were backwards digit score, visuospatial WM score and social WM mean RT.…”

“…Little is known of the role of dopamine in social cognition (Skuse, ; Skuse & Gallagher, ). However, we have previously shown that the rs4680 variant of COMT was associated with individual differences in performance of a social WM task in adults (Dumontheil et al, ). Importantly, the association was maintained when performance on standard verbal and visuospatial WM tasks was covaried out.…”