Genetics of decision-making

Abstract Persistent maladaptive decision-making is central to several psychiatric conditions, particularly addiction. Decision-making measures may serve as promising intermediate phenotypes (i.e. intervening mechanisms that link genetic variation to clinical vulnerability) and thus elucidate biological mechanisms that increase risk for addiction and related psychiatric disorders. This chapter focuses on the heritability and specific genetic correlates of the three most widely studied experimental measures of decision-making: impulsivity, measured by delayed reward discounting; disadvantageous decision-making, measured by the Iowa Gambling Task; and risk sensitivity, measured by the Balloon Analogue Risk Task. Despite some evidence of heritability for all phenotypes, the candidate gene studies reveal inconsistent findings. The extant literature is limited by small sample sizes, and a focus on select candidate genes, primarily related to dopaminergic and serotonergic systems. To advance the science, research will need to aggregate studies, increase sample sizes, explore subpopulations, and utilize genome-wide association studies to expand the genomic scope.