Overview. Choice drives virtually all behavior and is one of the most studied phenomena in psychology. The present proposal brings together three previously separate bodies of knowledge to further illuminate the nature of choice processes, with a particular emphasis on choice justification (a phenomenon involving increased preference for a chosen option and decreased preference for a rejected option). At the heart of the proposal is a formulation of a Gene X Situation X Culture Interaction Framework. Although the present effort is ambitious, recent developments in three relevant areas of research make the effort, not only possible, but also potentially fruitful.
Specifically, from cultural psychological work we know that choice justification is ubiquitous and, yet, the situations in which it occurs vary systematically across cultures: Whereas European Americans (who tend to see themselves as independent from others) justify choices they make for themselves, Asians (who tend to see themselves as interdependent with others) justify choices they make for their friends. From the neuroscience of decision-making, we know that choice justification occurs at the mesocorticolimbic neural pathway of reward processing. Third, from genetics we know that the neural pathway of reward processing is regulated closely by several dopamine system related genes. In combination, these three bodies of literature add importantly to the current view that choice making is neither static nor merely cognitive. Instead, choice making is best conceptualized as an open, dynamic process that receives constant input from genes, situations, and culture.
To investigate how choice justification depends on genes, situations (i.e., self vs. friend choice), and culture (i.e., European American vs. Asian), the current proposal involves one large-scale, cross-cultural imaging genetics study?the first of its kind. Both European Americans and East Asians who have either high or low genetic profiles of dopamine signaling capacity will be recruited. They will be scanned while making choices for themselves or for their friends. It is anticipated that when choices are made for the self, choice justification as revealed in activity in the ventral striatal area will be most pronounced for European Americans and, moreover, among European Americans the effect will be stronger for those with genetic profiles linked to high (vs. low) dopamine signaling capacity. In contrast, when choices are made for friends, the choice justification effect as revealed in the same ventral striatal region will be most pronounced for Asians and, moreover, among Asians this effect will be stronger for those with the genetic profiles associated with high (vs. low) dopamine signaling capacity.
Intellectual merits. Results from the proposed study will suggest that neither gene nor culture alone can predict the outcome even for simple choices. The unique contribution of this work will be to use neural mechanisms to reveal a Gene X Situation X Culture interaction effect with respect to a well-studied phenomenon of choice justification. The current work will therefore contribute to a more comprehensive understanding of how biological and socio-cultural processes interact with one another, thereby overcoming the traditional dichotomy between nature and nurture. Specifically, the results will challenge the common view that both culture and situation should be regarded as secondary, as an overlay on basic neural mechanisms determined by genes. To the contrary, culture and situation may be integral and necessary to genetic effects.
Broader impacts. If confirmed, the current prediction regarding Gene X Situation X Culture interaction effects will support the view that the study of human mind requires a multi-disciplinary point of view. For example, neither genetics nor neuroscience can be neatly separated from careful analysis of society and culture that provides the context for both genes and the bra