Sensory Development

n Robert Fantz in the 1960’s started using the Infant Paired Preference Procedure

Vision Testing

Sensory Development

n Can be used to study visual acuity

Visual Acuity Testing

n Paired Preference Procedure

n Forced Choice Preference Procedure

n Visual Evoked Potential– a form of ERP

Visual Evoked Potential

Visual Evoked Potential

Infant Vision Testing

Acuity Development

Visual Acuity

n At birth, acuity is approximately 20/400 to 20/800

n By 4 to 5 months infants are no longer “legally blind” (e.g., 20/200)

n Reaches 20/20 between 8 to months

n VEP suggests faster development– why?

What Infants See

Other Visual Limitations

n Can only see high contrast stimuli

Contrast Sensitivity Functions

What infants see

Discussion Assignment
Due: March 24

Why is vision so poor?

n Is it the eye?

n Cornea

n Astigmatism

n Iris

n Lens

n Retina

Changes in Cones

Retinal Receptive Fields

Why is vision so poor?

n The brain?

Scanning in Newborns

Color Vision

n When can babies discriminate color?

n Separating Hue, Brightness & Saturation

n Categorical Perception of Color

n R O Y G B I V

Color Categories

Auditory Thresholds

n Tested with High Amplitude Sucking Procedure

n Newborns hear above 27 decibels

n Can discriminate about 1 note on the musical scale

Newborn Speech Perception

n H.A.S. procedure is also used to study speech perception

n P. Eimas: Can newborn discriminate “B” from “P” sounds

n Can infants discriminate “R from “L”

n Or Pittsburgher’s

Harry from Hairy

Newborn Taste Abilities

n Can newborns discriminate the four basic flavors of :

n Sweet, Sour, Bitter, Salty

n Newborns prefer sweet and salty—why?

n Sweet flavors can sooth the newborn

Newborn Smell

n Newborns react positively and negatively to different smells

n Can infants detect the smell of their mothers?

World of the Newborn

n What is the world of a newborn like?

n How does this effect opinion about imitation research?