Evolution, Risk, and Neural Representation
Animals navigating through an uncertain world invariably face risks, such as the risk of starvation or predation. Ethological studies suggest that sensitivity to risk in animals has evolved to maximize their Darwinian fitness, which includes optimizing their probability of survival and reproduction, among other considerations. Concomitantly, natural selection has shaped the neural circuitry underlying risky decision making, and recent evidence suggests that risk may be explicitly represented in the brain. Neurons in monkey posterior cingulate cortex show sensitivity to risk during a decision-making task, whereas dopaminergic neurons appear to reflect the degree of reward uncertainty. While such studies bear direct relevance to human neurobiology, it is highly likely that human behavior toward risk was also shaped by evolutionarily recent neural specializations, such as the von Economo neurons. For this reason, both animal and human studies are necessary to reveal the neural mechanisms that underlie risky decision making.
uncertainty von economo neurons foraging macaques