Pub. date: 2010 | Online Pub. Date: December 16, 2009 | DOI: 10.4135/9781412972000 | Print ISBN: 9781412940818 | Online ISBN: 9781412972000| Publisher:SAGE Publications, Inc.About this encyclopedia
Perceptual Development: Touch and Pain
This entry describes how touch and temperature are perceived in neonates and the behavioral and physiological responses of neonates to pain. Touch stimuli cause changes in the skin that give us the sensations of pressure, warmth, and vibration. Touch is the earliest sensory system to develop in all species. When a human embryo is less than an inch long and less than two months old, the skin is already highly developed. When the palm is touched at two months gestation, the fingers grasp the palm. The fingers and thumb will close at three months when the palm is touched. The fetus can turn toward a tactile stimulus, much like a rooting reflex, and the fetus responds to electrical stimuli and puffs of air that are even difficult for adults to discriminate. These very sophisticated perceptual skills occur as early as three months gestation. Research suggests that touch discrimination by mouth ...