Neural and Autonomic Correlates of Approach-Avoidance Conflict Following Interoceptive Manipulation

Abstract

Decisions are often shaped not only by information surrounding us, but also by our mental-emotional state at the time of the decision. A racing heart, discomfort, or changes in nutrient needs can all influence whether an individual engages in a challenging situation or chooses to withdraw. We examined how bodily signals affect decision making and how they are represented in the brain. Using rhesus macaques performing tasks in which ongoing reward had to be weighed against the cost of enduring a mildly aversive stimulus, peripheral physiological state was pharmacologically altered to test whether changes in the body were sufficient to bias behavior. Perturbations that shift the body into a state mimicking high arousal biased behavior toward avoidance, showing that bodily state can causally influence cost–benefit decisions. To investigate the neural basis of this effect, we recorded single-neuron activity was recorded from anterior cingulate cortex and amygdala while monkeys performed the task. Activity in both areas exhibited ramp-like dynamics related to the timing of stopping, consistent with an evolving decision process. Despite this, we did not identify a clear neurophysiological correlate of the altered bodily state. When we examined the relationship between heart rate and neural firing to determine how bodily and neural signals covary, we found reliable correlations, but their temporal relationship suggests that the brain is leading the body, which may explain why we did not identify a neural correlation of peripheral manipulation. Together, these findings show that while bodily state can shape decisions, the task-relevant activity of cingulate–amygdala circuits is likely not biased by it.