Oxytocin and heuristic information processing: insights from an fMRI study

Based on the allostatic theory, we propose that the neuropeptide oxytocin, known to modulate social behavior in mammals, facilitates human coordination by enabling heuristic processing of several sources of information at once. We investigate this in two types of coordination problems: the Stag Hunt, which encourages cooperation by offering a win-win opportunity, and the Chicken game, which is by its nature competitive. Successfully switching back and forth from a mindset of joint pursuit (Stag Hunt) to one of conflict (Chicken), requires flexibility in how neural networks regulating attention, incentive motivation, and anxiety are regulated. We investigate if, and how, oxytocin neuromodulation influences this process by altering effective connectivity patterns in the brain. Participants (N=22) play a series of incentivized games while their brains are scanned with fMRI. The game matrices are always accompanied by pictures depicting angry or neutral faces. To assess effective connectivity, we conduct generalized psycho-physiological interaction analyses on several a priori defined seeds: the amygdala (initiating the fear response), the nucleus accumbens (triggering incentive motivation), and the empathy network, including the ACC and a-Insula. The results are in line with leading propositions for how oxytocin impacts social behavior. In the cooperative context of the Stag Hunt, oxytocin (relative to placebo) strengthens the connectivity of the empathy network, increasing the probability of cooperation, especially for risk averse individuals. In the competitive context of the Chicken game, oxytocin weakens insular influences on cortical facial processing regions. When facial cues are neutral, reduced amygdala connectivity with these regions leads to increased probability of competing. FWO-funded project