From social effort to social behavior: An integrated neural model for social motivation.

As humans rely on social groups for survival, social motivation is central to behavior and well-being. Here we define social motivation as the effort that initiates and directs behavior towards social outcomes, with the goal of satisfying our fundamental need for connection. We propose an integrated framework of social motivation which emphasizes the maintenance of optimal connection levels through effort exertion, regulating social approach and avoidance, which allow interpersonal synchrony. Together, these behaviors serve as basic building blocks of social behavior, and give rise to behaviors critical for collective living such as cooperation and empathy. We describe a neural model according to which social connection levels are monitored by the hypothalamus, while the anterior cingulate cortex and anterior insula respond to detected social deficiency. As adjustment is required, the social effort system - comprised of the thalamus and striatum - is activated. This system directs neural networks that permit interpersonal synchrony or, conversely, desynchronization, aiming to restore and maintain optimal connection by preventing isolation on the one hand, and exaggerated social closeness on the other hand. The proposed framework offers insights into disorders characterized by aberrant social motivation, potentially identifying neural dysfunctions that may inform novel interventions.