ABSTRACT
Individuals with genotypes that code for reduced dopaminergic brain activity often exhibit a predisposition toward aggression. However, it remains largely unknown how dopaminergic genotypes may increase aggression. Lower-functioning dopamine systems motivate individuals to seek reward from external sources such as illicit drugs and other risky experiences. Based on emerging evidence that aggression is a rewarding experience, we predicted that the effect of lower-functioning dopaminergic functioning on aggression would be mediated by tendencies to seek the environment for rewards. Caucasian female and male undergraduates (N = 277) were genotyped for five polymorphisms of the dopamine D2 receptor (DRD2) gene; they reported their previous history of aggression and their dispositional reward-seeking. Lower-functioning DRD2 profiles were associated with greater sensation-seeking, which then predicted greater aggression. Our findings suggest that lower-functioning dopaminergic activity puts individuals at risk for violence because it motivates them to experience aggression’s hedonically rewarding qualities.
Acknowledgments
We thank Richard Milich for his assistance in developing the study and for his help with data collection.
Disclosure statement
No potential conflict of interest was reported by the authors.
Notes
1 The sensation-seeking and aggression data from this sample appear in another manuscript on monoamine oxidase A (MAOA) genotypes and aggression (Chester et al., Citation2015). However, these data have not previously been analyzed in their relation to DRD2 genotypes.