CARTA: Human Brain Specializations Related to Language and Theory of Mind with James Rilling

James Rilling explains how comparative primate neuroimaging reveals human neurobiological specializations in brain tracts supporting language and theory of mind.

Humans excel at transmitting ideas, skills, and knowledge across generations, and at building on those competencies in a cumulative manner. James Rilling, Professor of Psychology at Emory University, explores how the transmission of our cumulative culture is assumed to depend on both language and mental perspective-taking, or theory of mind. If humans have specialized abilities in these domains, we must have neurobiological specializations to support them. Our research has used comparative primate neuroimaging to attempt to identify such specializations. The arcuate fasciculus is a white matter fiber tract that links Wernicke’s and Broca’s language areas. It is known to be involved in multiple, high level linguistic functions such as lexical semantics, complex syntax, and speech fluency. Using diffusion weighted imaging and tractography, we have demonstrated human specializations in the size and trajectory of the arcuate fasciculus that may partially explain human linguistic abilities. Theory of Mind depends on a set of cortical regions that belong to a neural network known as the default mode network that is functionally connected, highly active at rest, and deactivated by attention-demanding cognitive tasks. We and others have used functional neuroimaging to show that chimpanzees and other primates appear to have a default mode network that is similar to that of humans. However, the non-human primate default mode network seems to have weaker connectivity between certain key nodes, suggesting that these connections could play a role in human theory of mind specializations. Recorded on 02/27/2026. [3/2026] [Show ID: 41329] Donate to UCTV to support informative & inspiring programming: uctv.tv/donate Learn more about anthropogeny on CARTA's website: carta.anthropogeny.org/ More videos from: CARTA - The Idea Organ (uctv.tv/carta-idea-organ) Explore More Science & Technology on UCTV (uctv.tv/science) Science and technology continue to change our lives. University of California scientists are tackling the important questions like climate change, evolution, oceanography, neuroscience and the potential of stem cells. UCTV is the broadcast and online media platform of the University of California, featuring programming from its ten campuses, three national labs and affiliated research institutions. UCTV explores a broad spectrum of subjects for a general audience, including science, health and medicine, public affairs, humanities, arts and music, business, education, and agriculture. Launched in January 2000, UCTV embraces the core missions of the University of California -- teaching, research, and public service – by providing quality, in-depth television far beyond the campus borders to inquisitive viewers around the world. (uctv.tv)