This study will examine the similarities and differences of face processing in the developing brains of humans (children, adolescents, and adults) and non-human primates (NHPs) using functional magnetic resonance imaging (fMRI) to explore the functional neural circuitry involved in face processing. The overall scientific goal is to characterize the large-scale anatomical and functional brain networks in humans and NHPs for the perception of faces and for the processing of emotions in the face. Both capacities are critical for highly social organisms, but species-specific experiences may modulate these networks differently. A better understanding of brain connectivity patterns for face processing in humans and non-human primates can help develop animal models of typical and atypical social development. Such findings can be used to target behavioral or pharmacological interventions for conditions like autism spectrum disorder or Williams syndrome.