Emerging evidence suggests that the serotonergic and dopaminergic influences on action inhibition in the reversal learning task are mechanistically linked. Specifically, we found a relationship between individual differences in the ability to inhibit inappropriate responses in a reversal learning test and brain monoamine transmission in monkeys found a statistical interaction between levels of serotonin in the orbitofrontal cortex and dopamine in dorsal striatum that predicted action inhibition.156 These data indicate that serotonin and dopamine interact to influence response inhibition, rather than simply acting as two distinct and orthogonal influences.
