CHAPTER 4 INFANT PERCEPTION AND COGNITION distribute IN THIS CHAPTER or BASIC PERCEPTUAL ABILITIES OF YOUNG PERCEPTUAL NARROWING INFANTS Perceptual Narrowing for Facial Discrimination METHODOLOGIES USED TO ASSESS INFANT Perceptualpost, Narrowing in Speech Perception PERCEPTION Perceptual Narrowing and Music “This Sucks”: Using Infant Sucking Perceptual Narrowing Within Intersensory to Provide Insight Into Infant Perception Integration Visual Preference Paradigm Perceptual Narrowing as an Evolved Habituation/Dishabituation Paradigm copy, Social-Cognitive Mechanism DEVELOPMENT OF VISUAL PERCEPTION HOW DO WE KNOW WHAT BABIES KNOW? Vision in the Newborn THE VIOLATION-OF-EXPECTATION METHOD Development of Visual Preferences CORE KNOWLEDGE Development of Face Processingnot Object Representation AUDITORY DEVELOPMENT Early Number Concepts Speech Perception Newborn Statisticians? Arguments Against Core Knowledge Music Perception Do WHAT IS INFANT COGNITION MADE OF? COMBINING SENSES- Intersensory Integration KEY TERMS AND CONCEPTS Intersensory Matching SUGGESTED READINGS Proof udrey tells of an unusual preference in despite the fact that Audrey expressed milk her healthy 9-pound newborn daughter equally well from both. Michelle’s preference AMichelle. For the first several weeks of was the left breast, the one over her mother’s Draftlife, Michelle would nurse only from one breast, beating heart, a sound Michelle had heard from 92 Copyright ©2017 by SAGE Publications, Inc. This work may not be reproduced or distributed in any form or by any means without express written permission of the publisher. CHAPTER 4 INFANT PERCEPTION AND COGNITION 93 the time her auditory system began to func- to know where perception ends and cogni- tion several months after conception. Michelle tion begins (see, for example, L. B. Cohen & would nurse from the left breast only and inevi- Cashon, 2006, for a review). Perception is usu- tably fall asleep, presumably being soothed not ally defined as involving the organization of only by the milk she was consuming but also by the sensations (for example, sights, sounds, the familiar sound she was hearing. smells), whereas cognition deals more with If you ask most people what newborn babies what we do with those perceived sensations do, the answer you’ll likely get is, “Sleep, (for example, classifying items or events into eat, cry, and soil their diapers.” This is true categories, solving problems, memorizing). In enough, but newborns are also making sense this chapter, we first examine the developing of their world. They are perceiving (hearing, perceptual abilities in infants anddistribute then look seeing, smelling) and learning about events at some basic cognitive abilities, focusing on that surround them, and have been for some aspects of what has beenor called core knowl- time prior to birth. Not all that many years edge—specifically, infants’ understanding of ago, well-informed people believed that infants object representation and babies’ abilities to enter the world unable to perceive sights and make sense of quantitative information. Other sounds. When I (DB) was teaching my first topics related to infant cognition are examined child development class as a graduate student in later chapters.post, in the early 1970s, I stated that newborns can see, meaning that they can tell the difference between two visual displays. A middle-age woman informed me that I was wrong, that BASIC PERCEPTUAL newborns cannot see. She had had four chil-copy, ABILITIES OF YOUNG INFANTS dren, and her obstetrician and pediatrician had both told her that babies were functionally The study of infant perception has been one blind at birth and learned to see duringnot their of the most successful endeavors in the field first month of life. Newborns are far from of cognitive development over the past half mental giants, but they do enter the world able century (see S. P. Johnson & Hannon, 2015). to perceive information withDo all their senses. What infants perceive and know was once Furthermore, babies have- some perceptual thought to be beyond the limits of science. biases. Some sights, sounds, and smells are However, the development of often simple inherently more pleasing to them than others, techniques—using behaviors that infants, even and they learn to prefer additional sensations newborns, can control themselves to peek into during the first weeks of life. their minds—has permitted developmental But infants,Proof even newborns, do more psychologists to get a relatively clear picture than perceive their world. As the example of what infants perceive and how their percep- of Michelle suggests, they are also learning, tions change over time. something that most people call cognition. Most research on infant perceptual devel- DraftEven among experts, it’s not always easy opment has concerned audition (hearing) and Copyright ©2017 by SAGE Publications, Inc. This work may not be reproduced or distributed in any form or by any means without express written permission of the publisher. 94 CHILDREN’S THINKING vision. This is partly because of the importance and display more advanced cognitive and of these two senses for human information pro- motor skills than do normally treated preterm cessing and because vision in particular shows babies (see Honda et al., 2013; Schanberg & substantial development during the first year Field, 1987). This research has led to an of life. The development of audition and vision increased prevalence of skin-to-skin care, also are discussed in separate sections later in this known as kangaroo care, in neonatal intensive chapter. care units and newborn nurseries (see Johnston Research on other senses has also been con- et al., 2014). ducted, of course. For example, it was once The chemical senses (olfaction and taste) tend believed that newborns were relatively insensi- to develop early and are quite well developed tive to pain. More recent research, however, shortly after (and even before) birth.distribute In fact, a clearly demonstrates that they do, indeed, per- pregnant woman’s diet can influence taste pref- ceive pain (Delevati & Bergamasco, 1999), and erences in her newborn. Thisor was illustrated by some evidence indicates that, for extremely a study in which some women consumed anise- low birth weight (ELBW) infants (below 1,000 flavored food during pregnancy whereas others grams, or about 2.2 pounds), their response to did not. At birth and 4 days later, infants born pain is affected by repeated painful episodes, to anise-consuming mothers showed a prefer- which are often necessary for preterm infants ence for anisepost, odor, whereas those born to non- (Grunau et al., 2001). When tested at 8 months anise-consuming mothers displayed aversion or of age, the number of invasive procedures neutral responses to anise (Schaal, Marlier, & ELBW infants had from birth was associated Soussignan, 2000). Young infants can also tell with reduced facial and heart-rate reactions to the difference among a wide range of odors pain (blood collection). Yet other studies report copy,early in life (Steiner, 1979), and they develop that children who were exposed to more pain preferences for certain odors within the first as preterm infants experience increased sen- week. In a study by Aidan Macfarlane (1975), sitivity to pain in childhood and adolescence,not for example, 6-day-old nursing babies were able compared to their full-term peers. Fortunately, to discriminate the odor of their mothers from these threshold differences do not seem to per- those of other women. In this study, mothers sist into adulthood; adults’ self-reportsDo indicate wore breast pads in their bras between nurs- there is no increased prevalence- of pain syn- ings. Two breast pads—one from the baby’s dromes for those born at extremely low birth mother and the other from another woman— weight (see Grunau, 2013, for a review). New- were placed on either side of an infant’s head. borns also respond to another skin sense, that of Although no differences in infants’ behaviors touch, or tactile stimulation. Actually, research were seen in this situation at 2 days of age, by with both animals and human preterm infants 6 days of age babies were turning to their own indicates thatProof tactile stimulation is important in mother’s pad more often than to the pad of ameliorating pain responses in particular and another woman. That is, not only can babies promoting normal growth and development discriminate odors, they quickly learn to make in general. For instance, very small preterm associations with odors and to modify their Draftinfants who receive extra tactile stimulation behavior accordingly. In subsequent work using gain more weight, spend more time awake, a procedure similar to that of Macfarlane, Copyright ©2017 by SAGE Publications, Inc. This work may not be reproduced or distributed in any form or by any means without express written permission of the publisher. CHAPTER 4 INFANT PERCEPTION AND COGNITION 95 researchers found that infants develop a prefer- behavior that an infant can control and then use ence for the odor of milk versus amniotic fluid that behavior as an entry into what babies can (which they had been living in for 9 months) by perceive. For example, the Macfarlane (1975) 4 days of age (Marlier, Schaal, & Soussignan, study just presented took advantage of babies’ 1998) and that bottle-fed, 2-week-old infants abilities to turn their heads in one direction or preferred the breast odor of a lactating female another to determine if they could discriminate to that of a nonlactating female (Makin & and develop a preference for certain odors. Such Porter, 1989). measures are considered implicit measures of infant cognition because they are thought to cap- ture aspects of cognition that are unconscious and Section Review cannot be expressed directly or verbally.distribute As we’ll discuss, these aspects include implicit memory, • From birth, infants actively use their per- such as familiarity. In contrast, explicit measures ceptual systems to acquire information or from their surroundings.