The Awakening of the Newborn Human Infant and the Emergence of Consciousness.

Consciousness emerges gradually before and after birth, not as an all-or-nothing event. Newborns become aroused at birth due to intense sensory stimulation and stress from transitioning to air; first breaths activate the locus coeruleus, indicated by large pupils. Infants appear aware of their bodies and can recognize their mother's facial expressions, voice, and smell. A default mode network matures soon after birth, likely keeping the brain in a conscious state. Newborns are probably conscious, albeit at a low level. Fetuses show signs of consciousness after about 24 weeks of gestation, though they mainly sleep and are less aware of their environment. Before that, sensory nerves are not yet connected to the cerebral cortex.

Study at a glance

Abstract

Consciousness develops gradually in the womb and after birth, rather than being an all or none phenomenon. A newborn infant is aroused and wakes up at birth, due to the enormous sensory stimulation and stress that it undergoes during the transition from an aquatic environment to air. Its first breaths activate the locus coeruleus, as indicated by the large pupils of the newborn. The infant seems to be aware of its body and can recognise its mother's facial expressions, voice and smell. A default mode network matures soon after birth which appears to keep the brain in a conscious state. Thus the newborn infant is probably conscious, albeit at a low level. The foetus also shows some signs of being conscious after about 24 weeks of gestation, although it is mainly asleep in the womb and less aware of its environment. Before that stage, the nerves from the primary somatosensory, visual and auditory areas are not yet connected with the site of consciousness in the cerebral cortex.