Trajectories of brain and behaviour development in the womb, at birth and through infancy

Birth is often seen as the starting point for studying effects of the environment on human development, with much research focused on the capacities of young infants. However, recent imaging advances have revealed that the complex behaviours of the fetus and the uterine environment exert influence. Birth is now viewed as a punctuate event along a developmental pathway of increasing autonomy of the child from their mother. Here we highlight (1) increasing physiological autonomy and perceptual sensitivity in the fetus, (2) physiological and neurochemical processes associated with birth that influence future behaviour, (3) the recalibration of motor and sensory systems in the newborn to adapt to the world outside the womb and (4) the effect of the prenatal environment on later infant behaviours and brain function. Taken together, these lines of evidence move us beyond nature–nurture issues to a developmental human lifespan view beginning within the womb. Recent advances in imaging reveal that birth is a punctuate event in the development of brain and behaviour, which begins in the womb and continues in infancy. Meredith Weiss et al. review our understanding of this developmental trajectory based on current knowledge.