General anesthesia in early infancy accelerates visual cortical development.

How human brain function is established through protracted trajectories of development is not yet fully understood. Maturation of γ-aminobutyric acid (GABA) circuits drives critical periods of cortical development in animal models. Whether early functional inhibition similarly impacts the pace of human brain development remains unknown. Here, in a longitudinal study of 93 infants across a range of repeated exposures to general anesthesia shortly after birth, we observed a dramatically accelerated development of visual evoked potential (VEP) waveforms (but not their latency) consistent with a conserved biological mechanism across species. Such sequelae of prolonged GABA-active anesthesia in the first half year after birth may particularly impact those at-risk of altered excitatory-inhibitory circuit balance.