Many social species use eye contact to guide social behaviors. To study how visual cues shape social decision making, Franch et al. wirelessly recorded eye movements and activity in the visual and prefrontal cortices in two pairs of freely moving macaque monkeys. To retrieve food rewards, paired monkeys — who could see each other through a transparent screen — each had to press and hold a button and, crucially, had to do this simultaneously. The monkeys learned to coordinate and speed up their button presses over time. They also increasingly looked at their partner just before or after their own button press, which drove cooperation. Neuron populations in area V4 and the dorsolateral prefrontal cortex (DLPFC) encoded eye fixations on the reward and the partner, and DLPFC populations additionally encoded self- and partner-button presses and the decision to cooperate; decoding accuracy from these populations increased across sessions as the monkeys learned to cooperate. Moreover, spike timing during reward fixation, partner fixation and self-button presses became more coordinated between V4 and the DLPFC over time. These findings in freely behaving monkeys increase our understanding of visually guided social decision making and cooperation.

Original reference: Nature, https://doi.org/10.1038/s41586-024-07084-x (2024)