Early Sensory Capacities

Vision

• At birth the nerves and muscles and lens of the eye are still developing.
• Visual acuity varies from 20/240 to 20/640.
• Head movement indicates some vision.
• Infants show an interest in human faces soon after birth and prefer to look at faces rather than other objects.
  • Also show a preference for attractive, smiling faces.
• Prefer familiar over unfamiliar objects
• Visual acuity and color in newborns improve over time.

Visual Perception

• In the first two months of postnatal development, infants don’t perceive obstructed objects as complete, instead perceiving only what is visible.
• “Visual cliff” study was designed to test depth perception and visual expectations.
  • Infants will not crawl over the edge.
  • Their perception of affordances let them crawl or not crawl over the cliff.
  • Use of ‘binocular cues’ by age 3 to 4 months suggests depth perception even before infants can crawl.

Other Senses

• Hearing begins in the womb.
• Changes that take place during infancy involve perception of volume, pitch, localization.
• One of the keys to language development
• Newborns respond to touch and can feel pain.
• Newborns can differentiate odors.
• Sensitivity to taste is present even before birth.
• Over the first several months of age, infants begin to prefer salty tastes.