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.