Neural Representation of Learning Social Interactions in Non-Human Primates

Project Summary/Abstract. Visually guided social behavior, specifically cooperation, is one of the primary forces driving the evolution of intelligence and is critical to the health and survival of our species. Like humans, non-human primates also cooperate in natural and laboratory environments. Recent studies in the field of primate

social neurophysiology show that neurons in different brain regions can encode socially relevant variables, such as reward and actions of self and other. However, cortical areas have not been studied simultaneously during social interaction, and therefore neural network computations of social cognition are not well understood.

Furthermore, the neural correlates of learning advanced social concepts, such as cooperation, have not been studied and remain unknown. A major limitation preventing our understanding of the neural underpinnings of social cognition is the lack of a suitable framework to allow us to study how it emerges in real time from

interactions among brain networks. Traditionally, examining the neural bases of social behavior in non-human primates has been performed using stationary experiments in a laboratory environment in which the head and body are restrained. However, it has become increasingly understood that studying the brain in spatially

confined, artificial laboratory rigs poses severe limits on our capacity to understand the function of brain circuits. To overcome these limitations, I propose a novel approach using high-yield wireless neural recordings and eye tracking to study the cortical dynamics of social interactions across multiple cortical areas involved in processing

visual information (mid-level visual cortex V4) and decision making (dorsolateral prefrontal cortex) while two freely moving monkeys learn to cooperate for food reward. I hypothesize that learning social interactions will induce changes in 1) the encoding of socially relevant variables such as social visual cues and choice in each

area and 2) functional connectivity between areas. To investigate this hypothesis, I will record animals' behaviors (Aim 1), and eye data and neural activity (Aim 2-3) simultaneously as they learn to cooperate under different conditions. While learning cooperation, I expect animal behaviors, such as the coordination of their actions, to

improve (Aim 1). I also predict animal behaviors will be sensitive to reward value and fairness, showing less motivation to cooperate for small or unequal rewards, but will improve with learning (Aim 1). I anticipate the discovery of neural computations underlying social cognition within (Aim 2) and between brain areas (Aim 3) and

that neural encoding of salient information, such as social visual cues and actions, will improve as animals learn to cooperate. This project provides a novel method and use of analyses to study learning social interactions. This research will further our understanding of the social brain by elucidating the role of neural networks

underlying social cognition. Most importantly, the results of this investigation will provide long-term candidate brain areas and behaviors that can be targeted for therapeutic intervention in individuals suffering from social dysfunction.