سکوت

Information Processing
 

Piaget was a "grand" theorist of cognition throughout the life span, with an appreciation or shifts in the nature of cognition that occur at about ages 2, 6, and 12.
 

his sweeping stage overview contrasts with another view of infant cognition, one
 

that arises from information-processing theory, a perspective on human think-
 

ing processes modeled on computer analysis of data. No computer can match the
 

mind's capacity for reflection, creativity, and intuition. However, information-
 

processing theorists suggest that a step-by-step description of the mechanisms of
 

human thought, by analogy to the steps by which computers process data, aids
 

our understanding of the development of cognition at every age.

 

 

 

 

 

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Information-processing researchers look not only at such

Specific fields Of study as neuroscience and linguistics, but

also at the comprehensive processing or information, from

input through output. Information processing begins with

input in the form or sensory messages picked up by the five

senses; proceeds to brain reactions, connections, and stored

memories; and concludes with some form of output. For infants, the output might consist of moving a hand to uncover a

hidden object, or saying a word to signify recognition of a

person, Or focusing the eyes to demonstrate that a stimulus is

noticed.

Although many researchers in infant cognition do not explicitly use the information-processing perspective in their

work. this perspective helps tic together the various aspects

Of infant cognition that are the topic of extensive study and

exciting discoveries. We will review three of these aspects

now: affordances, categories, and memory. Each of these

refers to a step in information processing: Affordances concern perception (or, by analogy, input); categories refer to the organization Of

concepts by the brain (Or programming); and memory involves retrieval Of ideas

already learned or Of past experiences (or output).

Affordances

Perception. remember is the mental processing or information that at the

brain from the sensory Organs. It is the first step of inrormation processinq—the

input 10 the brain- One or the puzzles of adult development IS why two people can

have radically different perceptions or the same situation. The same question

applies to infants.

A lifetime or thought and research led Eleanor and James Gibson to Conclude that perception is far Trom an automatic phenomenon that every baby.

everywhere, experiences in the same way (E. Gibson, 1%9' J, Gibson, 1979). For

infants. as ror the rest or us, pemoption Is a ctKJnitive accomplishment that requires selection from a vast array of possibilities: -perceiving is active, a process

Of obtaining information about the "orld.... We dohft simply See, We look'

(E Gibson, Iga. p. 5).

The Gibsons contend that the environment (people, places. and objects)

affords, or offers, many opportunities to be FRrceived and to be used in a Wide

variety of ways (E Gibson. 1997). Each of these opportunities for perception and

interaction is called an affordance. Which particular affordances are perceived

and acted on depends on Tour ractors: sensory awamncss, immediate motivation, current development. and past experience.

As a simple example, a lemon may be perceived as something that affords

smelling, lasting, touching, viewing. squeezing. and biting (among

other things). Which affordance a particular person perceives and acts on depends on the four factors just mentioned. Consequently, a lemon might elicit

quite different perceptions from an artist about to paint a still life, a thirsty adult

in need Of a refreshing drink, and a teething baby wanting something 10 gnaw

on. This example implies (correctly/ that affordances require an ecological nt

tween the individual and his or her environment. Hence, affordances arise

from specific qualities of an object and from the way the individual subjectively

perceives the object.

Affordances are not limited to objects; they are also perceived in the physical

characteristics of a setting and the living creatures in it (Recd. 1993). A toddlers

idea or what affords running might be any unobstructed surface—a rneadow, a

 

 

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long hallway in an apartment building, Or an empty road. To an adult

eye, the degree t0Avhich these places afford running may be restricted

by such factors as a bull grazing in the meadow. neighbors in the hallway, or traffic on the road.

Graspable?

All the senses are active processors from the moment of birth. Infants

learn what parts of the visual array best afford focusing, what sounds

merit listening, and so on. In terms of actions controlled by the infant, the

grasping and sucking reflexes are among the first to afford information.

Graspabitity—whether an object is the right size, shape, and texture

for grasping and whether it is within reach—is an early affordance. This

is vital information, since infants learn about their world by handling

objects. Extensive research has shown that infants perceive graspability

long before their manual dexterity enables them to actually grasp successfully.

They look intently at objects that seem graspable and ignore ones that do not,

even before they are able to aim and adjust their arms and hands to grab the

possibly graspable thing (Wentworth et alv 2000). By 5 months, infants are able

to grab objects successfully, usually taking longer to coordinate their hand movements than do older babies and adults. This shows that deliberate and thoughtful perception precedes an action that will soon become automatic (McCarty &

Ashmead, 1999).

The fact that babies perceive graspability so early helps explain how they explore a face. Once they have some control over their arm and hand movements,

they will grab at any face that comes within their reach. But their grabbing is far

from haphazard: They do not grab at the eyes or mouth (although they might

poke at them), because they already perceive that these objects are embedded

and thus do not afford grasping. A tug at the nose or ears is more likely, because

these features do afford grasping. Even better are eyeglasses, earrings, and long

mustaches—all of which are quickly yanked by most babies, who perceive at a

glance the graspability these objects afford.

Sudden Drops

The affordances that an infant perceives in common objects evolve as the infant

gains experience with those objects. An example is provided by the visual cliff,

an apparatus designed to provide the illusion of a sudden dropoff between one

horizontal surface and another.

 

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Researchers once thought that perception of a visual cliff was purely a matter of visual maturity: 8-month-olds could see the difference; younger babies,

because of their inadequate depth perception, could not. "Proof- came when

6-month-olds could be enticed to wiggle forward over the supposed edge of the

visual cliff, in contrast to 10-month-olds, who fearfully refused to budge, even

When their mothers called them (E. Gibson & Walk, 1960).

Later research found, however, that this hypothesis was wrong. In fact, even

3-month-olds notice the difference between a solid surface and an apparent cliff,

as evidenced by their slowed heart rate and wide-open eyes when they are

placed over the -edge." But they do not realize that one affordance of the cliff is

falling. nat realization comes when they start crawling, and their memory Of a

caregiver's fear (or perhaps their own tumble off a bed) teaches them that the

edge of a precipice (as in stairs that go down) affords danger and pain (Campos

etal., 1978).

Movement and People

Despite all the variations from one infant to another in the particular affordances

they perceive, two general principles of perception are shared by all infants. One

is dynamic perception, which is perception primed to focus on movement and

change. Infants love to attend to objects that move. As soon as they can, they

move their own bodies—grabbing, scooting, crawling, walking—and, to their delight, these movements change what the

world affords them. Likewise, other creatures that move, especially their own caregivers, are among the first and best

to teach a baby not to chase and grab a dog, a cat, or a

cockroach.

second universal principle of infant perception Is

that they are rascinated by other people. This characteristic

may have evolved over the many centuries when humans Of

all ages survived by learning to attend to, and rely on, each

other. Ihis fascination underlies another of the surprising

competencies or young infants; coordinating vision and hearing by matching face with voice.

An experiment that demonstrates this begins with two side-by-side frames

on a video screen. with two people racing the camera and talking. Only one v•oice

is heard on the audiotape. By 6 months, infants match the speakers' voice to the

face on the film. ignoring the face or the other person. whose mouth movements

are not synchronized with the sounds (Kuhl & Meltzoff, 1988). With this task as

with all affordances, selectivity is apparent- Seven-month-olds connect speech

and race when the person is happy, angry. or interested. However. they prefer

not to look at a sad face, even when the voice matches it. Tliey would much

rather stare at the happy face even when it does not match the voice (Soken &

Pick 1999).

One team or researchers who study infant matching of face and •voice refer

directly to affordances:

Given that infants are frequently exposed to their caregivers' emotional displays

and further with om»rtunitics to view the affordances (Gibson, 1959,

1979) of those emotional expressions, wc propose that the expressions Of familiar

persons are meaningful to infants very early In life.

tKahana•KalnW1 & p. 361

As with the earlier research, these researchers presented infants with two

moving images on a video screen. Both images were women visibly expressing

 

 

 

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joy or sorrow, accompanied by an audiotape of one woman's happy or sad talk.

This study differed from earlier work in two ways. First, the infants were much

younger, only 3% months old. Not surprisingly, given their immaturity, when the

infants did not know the woman, they failed to match the verbal emotion with

the face. Like the 7-month-old infants in the study just mentioned, they looked

slightly more at the happy face, but unlike them, they showed no sign of matching visual and auditory stimuli.

The second difference between this study and earlier research was that halt

the infants saw a video of a stranger, but the other half were presented with two

images (happy and sad) of their own mothers, with an audio that was either their

mother's happy words or her sad ones. In this case, the infants successfully

matched visual and vocal emotions. They looked longest of all at their happy

mothers, talking in a happy way, but they also looked at their sad mothers when

the audio they heard was their mother's sad voice—an amazing display of the

very young infant's ability to perceive and speech.

These experimenters noticed something else that was not reported in the

earlier research. When they saw and heard their happy mothers, as opposed to

the happy strangers, infants smiled twice as quickly, seven times as long, and

much more brightly (with cheeks raised as well as mouth upturned) (Kahana-Kalman & Walker-Andrews, 2001). Obviously, experience had taught these babies

that a smiling mother affords joy, especially if you smile back. The affordances of

a smiling stranger, however, even on a video, are more difficult to judge.

Categories and Concepts

Understanding objects or peoplc one by one, moment by moment, is much easier

than forming a general concept or perception, especially when that concept

seems to include an entire category of experiences. Yet that is precisely what infants apparently do—they categorize affordances within the first year of life. As

we just saw, very young infants quickly form at least two categories for adult

women: their own mother in one category and smiling strangers in another. You

will learn in Chapter 7 that infants form other social categories, responding quite

differently to fathers than to mothers, to children than to adults, and to friends

than to strangers. Even more impressive is that infants form categories using intellectual, not social, concepts.

Early Categories

Infants younger than 6 months can categorize objects on the basis of their shape,

color, angularity, density, relative size, and, to the amazement of researchers,

number (up to three objects) (Haith & Benson, 1998). Taken as a whole, the evidence suggests that young infants do not merely perceive the difference between

shapes (such as circles versus squares) or relative sizes (such as larger and

smaller); they also apply organizing principics that enable them to develop a concept of what is, or is not, relevant for inclusion in each category. Many researchers believe that a rudimentary understanding Of such categories may be

biologically based ("hard-wired" in the brain) but that experience with different

objects and events is also essential for developing the innate ability to sort things

into categories.

To use the term introduced in Chapter 5, basic categories are experience-expectant. For instance, the brain awaits visual stimuli of some curved things and

some angular things; once these things are seen, the category is quick to emerge.

Also important is basic number—at least the distinction between "one" and

*more than one." Babies also understand simple spatial relationships. For example, infants as young as 3 months seem to understand 'above" and "below.- At

least, after they see several depictions Of a small diamond-shaped dot above a