A role for the serotonin 2A receptor in the expansion and functioning of human transmodal cortex
“Integrating independent but converging lines of research on brain function and neurodevelopment across scales, this article proposes that serotonin 2A receptor (5-HT2AR) signalling is an evolutionary and developmental driver and potent modulator of the macroscale functional organization of the human cerebral cortex. A wealth of evidence indicates that the anatomical and functional organization of the cortex follows a unimodal-to-transmodal gradient. Situated at the apex of this processing hierarchy—where it plays a central role in the integrative processes underpinning complex, human-defining cognition—the transmodal cortex has disproportionately expanded across human development and evolution. Notably, the adult human transmodal cortex is especially rich in 5-HT2AR expression and recent evidence suggests that, during early brain development, 5-HT2AR signaling on neural progenitor cells stimulates their proliferation—a critical process for evolutionarily-relevant cortical expansion.”
Basically what I think they are arguing here is that the Serotonin 2A receptor (5-HT2AR) is a major part in the rapid expansion of the human cerebral cortex. And what works on these seemingly vital receptors? You guessed it, psychedelics. With the sacred mushrooms of the genus Psilocybe being the most accessible psychedelic in paleolithic times it’s a fair assessment that mushrooms were part of the stimulus in the increased signaling that helped the growth of our brains.
Oxford Academic