CHAPTER 5
◦ Key battleground of nature vs. nuture debate
◦ Nativism (inborn) vs. empiricism (skills are learned)

WAYS OF STUDYING EARLY PERCEPTUAL
SKILLS
◦ Preference technique devised by Robert Fantz
◦ Baby given two options, researchers track which
one they look at more
◦ Another option  habituation
 Baby shown an object until habituated
 A similar object is then shown to see if baby notices
whether it is different
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EXPLANATIONS OF PERCEPTUAL
DEVELOPMENT
◦ Arguments for Nativism
 Researchers have found more and more skills already
present in newborns and very young infants
 Newborns don’t have to be taught what to look at
 Studies comparing preterm babies shows importance
of maturation age on perceptual development
◦ Arguments for Empiricism
 Research that shows some level of experience needed
 Aslin – maintenance (ie. decrease of visual perception)
 Attunement – deprivation of visual experiences in early
stages
◦ Integrating the Nativist and Empiricist Positions
 Development of perceptual skills is result of
interaction between inborn and experiential factors (ie.
nature AND nuture
 Similar to hardware and software
 Making visual discriminations is hardware
 Specific discriminations and number of separate objects
will depend on experience

SEEING
◦ Until 25 to 30 years ago, many medical texts stated
infants were blind
◦ Visual acuity
 Infant’s at birth is 20/200 to 20/400, but improves
rapidly during the first year
 Most reach 20/20 by about 2 years of age
 Infants see quite well close up
◦ Tracking Objects in the Visual Field
 Following a moving object
 Initially inefficient but improves rapidly
 Some tracking at 2 months, but shift at around 6 to 10
months
◦ Colour Vision
 Cells necessary to perceive red and green are clearly
present by 1 month, perhaps at birth, blue probably
present at that time as well

HEARING AND OTHER SENSES
◦ Auditory Acuity
 How newborns hear better than how they see
 Children’s hearing improves up to adolescence
 Within general range of pitch and loudness, newborns
hear as well as adults
 With high-pitched sounds, acuity is less than adult
◦ Detecting Locations
 Determining general location of sound exists at birth and
improves
 Sounds arrive at one ear before another
 Newborns will turn their head
 Specific locations not well-developed
 27 degrees at 2 months, 12 degrees at 6 months, 4 degrees
at 18 months
◦ Smelling and Tasting
 As in adults, intricately related
 Newborns appear to respond differently to the four tastes
◦ Sense of Touch and Motion
 The best developed of all
 Considerable fine-tuning occurs in first year
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LOOKING
◦ Depth Perception
 Binocular cues – involving both eyes
 Pictorial information – monocular cues
 ie. linear perspective (railroad tracks seemingly getting
closer)
 Kinetic cues – objects near you move more than
objects farther
 kinetic information perhaps used beginning at 3
months
 Binocular cues used at about 4 months
 Pictorial cues used at about 5 to 7 months
 The Gibson/Walk visual cliff experiment
◦ What Babies Look At
 From the beginning, babies look at the world in a nonrandom way
 In first 2 months, focused on where objects are
 Between 2 to 3 months, focus on what an object is as
opposed to where
 Begin noticing patterns, horizontal/vertical, big/small
◦ Faces: An Example of Responding to a Complex Pattern
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Little indication that faces are uniquely interesting to infants
Face processing as young as 3 months
Prefer attractive faces and prefer mother’s face
Recognition of voice directs attention to face
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LISTENING
◦ From 1 month, infants can discriminate between sounds
◦ By 6 months, can discriminate between two-syllable
words
 Male or female doesn’t matter
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COMBINING INFORMATION FROM MANY SENSES
◦ Intersensory integration and cross-modal transfer
◦ Cross-modal as early as 1 month, more common at 6
months
◦ Intersensory is important in infant learning
 Better able to recognize a new stimulus then with either
stimulus alone
◦ Preference for looking at visuals that match with a sound
◦ Not a completely automatic process
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IGNORING PERCEPTUAL INFORMATION
◦ Child must acquire set of rules called perceptual
constancies
 ie. size constancy, shape constancy, colour constancy
◦ OBJECT constancy
 Remain the same even when sensory information has
changed
 Babies show this at 3 or 4 months and become more
skilled
◦ When learning to read, child has to unlearn some
shape constancies (ie. b and d, p and q)
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INDIVIDUAL DIFFERENCES IN PERCEPTUAL
SKILLS
◦ Like physical development, perceptual development
shows significant individual variations
◦ Faster habituation by 4 to 5 months is associated
with higher IQ at 3 or 4 years of age

OBJECT PERCEPTION
◦ Babies are born with built-in assumptions
 ie. connected surface principle
◦ Other skills are learned through experience
 Babies “hypotheses” are modified based on
experiences
 Infants’ understanding of objects is the foundation
upon which object concept is constructed and applied
to real-life interaction over the first 3 years
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OBJECT PERMANENCE
◦ Strongly emphasized in Piaget’s theory
 Stages in the Development of Object Permanence
 First sign is at 2 months of age
 Child develops schema or expectation about permanence
 not developed enough to lead to searching for an object
 Changes at 6 to 8 months
 By 12 months, objects continue to “exist” even when no
longer visible
◦ Object Permanence and Cultural Practices
 Progression toward object permanence across first 18
months quite similar

EARLY DISCRIMINATION OF EMOTIONAL
EXPRESSIONS
◦ Infants begin to pay attention to social/emotional
cues at about 2 or 3 months
 More when face is turned toward them
◦ Also beginning to notice and respond differently to
variations in others’ emotional expressions
◦ By 5 to 7 months, can begin to read one “channel” –
facial or vocal
◦ Later in year one, develop “social referencing”
responding to cues and reacts with equivalent
concern or fear

CROSS-CULTURAL COMMONALITIES AND
VARIATIONS
◦ Similarity with same “basic” emotions
 ie. fear, happiness, sadness, anger and disgust
◦ Cultures have different rules about which emotions
may be expressed and which must be masked