The condition or state of the infant when the eyes are open and can make conjugate movements to pursue a moving target, respirations are relatively regular but more variable and faster than during quiet sleep, and when the limbs are either at rest except for small movements (inactive alert wakefulness) or they move intermittently in a smooth trajectory. The infant either does not vocalise or makes occasional non-cry ‘cooing’, with ‘babbling’ sounds occurring after about 3 months of age.
See Babbling, Behavioral state, Behavioral state concept, Cooing, Pre-reaching, Wakefulness