Infancy Chapter 5

Reflexes Newborn Reflexes Survival Primitive breathing, sucking, swallowing Primitive Babinski, swimming, grasping

Infant States

Infant States Most time asleep Average 2-year-old = 12-13 hours 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 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) Held & Hein 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