Infancy
Chapter 5
Reflexes

Newborn Reflexes
– Survival
 breathing, sucking, swallowing
– Primitive
 Babinski, swimming, grasping
Infant States
Infant States

Most time asleep
– 16-18 hours a day
Average 2-year-old = 12-13 hours
 Changes  brain maturation and social
environment

Do
infants
see/hear/smell/feel the
same things we do???

Sensation

Perception
Assessing Infant Perception

Preferential Looking Technique
Assessing Infant Perception

Preferential Looking Technique (con’t)
– Patterns to solids
– Infant visual acuity
– Faces to other patterns
– Tells us preference
– No preference doesn’t prove infants can’t
discriminate…
Assessing Infant Perception

Habituation
– Familiarity  lack of response
– Dishabituation
– Three methods
 Looking
 High amplitude sucking
 Heart rate
– Several presentations of a stimulus for
habitutation to occur
Assessing Infant Perception

Evoked Potentials
– Brain waves
 Different brain wave patterns
Learning in Infancy

Classical Conditioning
– Unconditioned stimulus (UCS) elicits an
unconditioned response (UCR)
– Neutral conditioned stimulus (CS) paired with
(UCS)
– Eventually CS elicits a conditioned response
(CR)
– Possible for newborns, but must have survival
value
Learning in Infancy

Operant Conditioning
– Learner emits a response
– Consequences
 Repeat favorable, limit unfavorable
– Newborns learn very slowly, rate increases
with age
– At 2 months, context-dependent
Figure 5.15 When ribbons are attached to their ankles, 2- to 3-month-old infants soon
learn to make a mobile move by kicking their legs. But do they remember how to
make the mobile move when tested days or weeks after the original learning? These
are the questions that Rovee-Collier has explored in her fascinating research on infant
memory.
Learning in Infancy

Observational Learning –
– Newborn imitation
– Imitation of novel responses
– Immediate imitation, then deferred imitation
Sensory/Perceptual Capabilities

Touch, Temperature, and Pain
– Particularly sensitive on hands, feet, and
mouth
– Temperature
– Pain – even at 1 day
– Dishabituate sucking to novel objects at 3
months
– Prefer to manipulate novel objects at 5
months
Sensory/Perceptual Capabilities

Taste
– Sweet, salty, sour, bitter
– Prefer sweet
– How do we know???
– Present before birth?
Sensory/Perceptual Capabilities

Smell
– Unpleasant smells
– Breastfed babies recognize mothers
 6 days
 2 day old cannot
– Bottle-fed infants later
Sensory/Perceptual Capabilities

Hearing
– Discriminate sounds
 Loudness
 Duration
 Direction
 Frequency
– Prefer mother’s voice
– Phonemes
– Hearing loss
Sensory/Perceptual Capabilities

Vision
– Least mature
– Muscles weak
– Cells in retina not
mature or dense
– Optic nerve and “relay”
pathways immature
– Visual acuity poor
 Neonate 20/600
 6 months 20/100
 Adultlike at one year
Sensory/Perceptual Capabilities

Vision (con’t)
– Spatial frequency gradings
Sensory/Perceptual Capabilities

Vision (con’t)
– Color perception
 Certain hues
 By 2-3 months, all basic colors
 By 4 months, group different shades into same
category
– Biological timetable
Visual Perception

Identifying boundaries – Spelke
– 3 to 5 month olds shown two objects
– touched vs. separated
– stationary vs. moving (either independently
or together)
Visual Perception

Results
–
objects touched, stood still, or moved in the same
direction  reached for them as a whole
–
objects separated or moved in opposite directions
 behaved as distinct
–
repeated with objects of different shapes, colors
–
motion and spatial arrangement  identification of
objects; not shape, texture, and color
•
Figure 5.7 Perceiving objects as wholes. An infant is habituated to a rod partially
hidden by the block in front of it. The rod is either stationary (A) or moving (B).
When tested afterward, does the infant treat the whole rod (C) as “familiar”? We
certainly would, for we could readily interpret cues that tell us that there is one long
rod behind the block and would therefore regard the whole rod as familiar. But if the
infant shows more interest in the whole rod (C) than in the two rod segments (D), he
or she has apparently not been able to use available cues to perceive a whole rod.
ADAPTED FROM KELLMAN & SPELKE, 1983.
Depth Perception
Visual Perception

Depth Perception (con’t)
– Radar: young infants in walkers
– Readily crossed deep side of cliff

Held & Hein
– Self-propelled movement
Visual Perception

Face Perception
– Newborns  faces over patterns (Fantz)
– Maurer & Barrera


habituated 1 and 2 month olds to scrambled face
test: infant saw 3 patterns, one at a time:
– the habituation pattern
– a different (symmetrical) scrambled face
– a naturally arranged face
Visual Perception

Face perception (con’t)
– 1 month: equal looking at all 3 test patterns
– 2 months: dishabituate to new patterns –
look most at natural face
Visual Perception

Particular faces by 3 months

Attractive over unattractive
– Langlois and colleagues
– Found in 3-, 6-, and 12-month-old infants, as
well as in older children and adults
Intermodal Perception

Integration at Birth?
– Yes: reaching for objects that are seen
– Yes: looking in the direction of sounds
– Yes: expecting to see source of sound, or to
feel objects that were reached for
Intermodal Perception

Integrating sensory information from 2 or
more modalities
– (differs from text…)

Spelke (1979): 4-month-olds film
Cross-Modal
Perception/Transference
Ability to recognize an object through one
sense that was familiar only through
another
 Some research connects cross-modal
transference and habituation speed with
later intelligence and language skills
