Newborns have well developed reflexes and sensory responses. Can respond and adapt to the environment from the first moments after birth. Abnormalities in reflexes: can be useful indicators for identifying visual and hearing problems, can be a sign of neurological problems. Infant state: a recurring pattern of arousal in the newborn ranging from alert, vigorous, wakeful activity, to quiet, regular sleep. Indicate that human behav is organized and predictable, and that human beings are not passive creatures that merely react to the environment. 2 basic infant states: waking and sleeping, each state includes variations. Newborn sleeps 70% of the time on average in a series of long and short naps. By 4 weeks fewer but longer periods of sleep. 8 weeks sleeping more during the night and less during the day. End of first year sleep through the night. Most mothers can distinguish types of cries but only of their own baby.