An evolutionary gap in primate default mode network organization
Cell Reports March 16, 2021 Clément M. Garin, Y. Hori, S. Everling et al.
The default mode network (DMN) in humans is active during rest and self-directed thought. Comparing the DMN across humans and non-hominoid primates (macaques, marmosets, and mouse lemurs) reveals major differences in connectivity. In non-hominoid primates, the medial prefrontal cortex shows weak engagement with the posterior cingulate cortex, whereas strong correlated activity between these regions is a key human DMN feature. Instead, a fronto-temporal resting-state network involving the medial prefrontal cortex appears consistently across non-hominoid species. These shared features among non-hominoid primates, absent in humans, indicate a substantial gap in DMN organization and its associated cognitive functions.