Cognition In Children

Usha Goswami

• Publisher: Psychology Press
• Year: 2014
• ISBN:
  9781317774648
• Edition: 1
• Topic: Psicología
• Subtopic: Historia y teoría en psicología

This textbook aims to provide a selective, but representative, review of work in cognitive development, grouped around themes that are familiar from textbooks of adult cognition. The book focuses on the question of what develops, rather than on why it develops. The findings of a given experimental study what develops are generally fixed, but the interpretation of what particular findings mean why is fluid. Some of the experiments discussed in this book have alternative explanations, and every student interested in children's cognition is invited to develop their own ideas about what different studies mean.

Cognition in infancy: Basic cognitive processes

1

Cognition can be defined as the set of processes that enable us to gain information about our environments—processes such as learning, memory, reasoning, and problem solving. Information processing is not an end in itself, however, as the goal of cognition is to give us control over our environment. A degree of control enables us to manipulate the environment to serve our needs and desires. This requires understanding—in order to have control, we need knowledge about causation. Cognitive development in a broad sense is thus the development of the set of processes that enable us to gain knowledge about causation.

The fundamental processes of cognitive development are learning, memory, perception, and attention. According to many theories, without some form of memory, infants would live in a constant world of the “here and now”. In order to remember, babies must learn what is familiar. A cognitive system cannot display memory without simultaneously displaying learning. At the same time, learning and memory in infants and neonates would be impossible if infants lacked adequate perceptual skills and adequate attentional mechanisms. Although there are some important immaturities in the visual system at birth (see Atkinson & Braddick, 1989), recent research has shown that the visual and auditory perceptual abilities of babies are much more sophisticated than was once supposed. In fact, recent research has revealed that surprisingly young babies have active cognitive lives.

Memory and learning

Memory is a good place to begin to study infant cognition. Memory is a cognitive process that begins to function within the womb, indicating that learning is also functional before birth. Evidence that babies begin storing memories while they are still in the womb comes from an ingenious study by DeCaspar and Fifer (1980), who tested babies’ memory approximately 12 hours after they had been born.

Neonate memory for the mother’s voice

It is known that infants can hear noises from inside the womb during at least the third trimester onwards (6-9 months). One sound that they hear a lot is their mother’s voice. She may be talking to other people during her daily routines, talking on the telephone, or even talking to the infant in her womb. If infants can remember the sound of their mother’s voice, then they should be able to distinguish her voice from the voice of a female stranger. In order to see whether infants were able to do this, DeCaspar and Fifer first measured how strongly infants sucked on a dummy in the absence of any auditory stimulus. They then introduced two tape recordings, one of the infant’s mother reading a story, and one of a strange woman reading the same story. For some infants, every time their suck rate increased compared to baseline, they were rewarded with the tape of their mother’s voice. Every time their suck rate fell below the baseline measure, they heard the tape of the voice of the stranger. For other infants, the contingencies were reversed. A low suck rate relative to baseline was rewarded with their mother’s voice, and a high suck rate relative to baseline was rewarded with the voice of the stranger.

Both groups of infants rapidly learned to suck at the appropriate rate to hear their mother’s voice. This shows that they remembered the sound of their own mother’s voice, and that it was a familiar and comforting stimulus. Even more impressive, they could remember the contingency in a second test session given on the following day Babies who had learned to suck strongly to hear their mother began by sucking strongly on the dummy, and those who had learned to suck slowly began by sucking slowly. The experimenters, however, had reversed the contingencies. Babies who had learned to suck strongly for their mother’s voice were now meant to suck slowly, and babies who had learned to suck slowly were now meant to suck strongly Around 80% of the babies learned to reverse their suck rate. This is good evidence for learning and memory in these extremely young babies. In fact, the ability to reverse a learned rule is considered to be a strong test of cognition in animals, and so the rapid learning found in these babies shows that day-old babies are at least as cognitively sophisticated as rats and pigeons, and are more cognitively sophisticated than goldfish, who cannot learn rule reversals even after thousands of trials!

Neonate memory for familiar stories

In order to provide a strong test of the idea that memory for the mother’s voice does indeed occur via learning in utero, rather than from very rapid learning during the first few hours after birth, DeCaspar and Spence (1986) conducted a further study in which mothers read three

stories onto a tape. The mothers then selected one of the three stories and read it every day during the last six weeks of their pregnancies. Following birth, the infants’ baseline suck rates were established, and the infants were then rewarded for sucking either above or below baseline by their mother’s voice reading the familiar story. If sucking fell to baseline, the infants heard their mother’s voice reading an unfamiliar story. DeCaspar and Spence found that the infants consistently sucked at the rate that was appropriate to produce the familiar story. Interestingly, a second group of infants showed the same pattern of preferences when tested with another mother’s voice reading the stories. DeCaspar and Spence argued that the target stories were preferred because the infants had heard them before birth. The babies had apparently learned something about the acoustic cues specifying a particular target passage as foetuses, and could recognise these cues even when a strange female voice was reading the story.

Memory for objects

Although the sound of one’s mother’s voice could be argued to be an unusually salient stimulus, infant memory for more mundane objects and events is also impressive. For example, Bushnell, McCutcheon, Sinclair, and Tweedie (1984) studied infants’ memory for pictures of simple shapes such as red triangles and blue crosses, which were mounted on wooden paddles. The infants were aged 3 and 7 weeks. Memory for a simple stimulus such as a yellow circle was first developed by asking the infants’ mothers to present the stimulus daily for a two-week period. The mothers were encouraged to show their babies the stimulus “actively” for two 15-minute sessions per day. The babies were then visited at home by an experimenter, who showed them the habituating stimulus and also a random selection of the other stimuli, varying in either colour, shape, or colour and shape. The aim was to test the infants’ memories for these different aspects of the stimuli. For example, to test colour memory, the baby might be shown a red circle rather than a yellow circle. To test memory for shape, the baby might be shown a yellow square instead of a yellow circle, and so on. Bushnell et al. found that the infants retained information about every aspect of the stimuli that they had been shown—shape, colour, and size.

Cornell (1979) used pictures of groups of such stimuli to study recognition memory in infants aged from 5 to 6 months. In addition to pictures of patterns of geometric forms (see Fig. 1.1), he also used photographs of human faces. The babies were first shown two identical pictures from Set 1 side-by-side, followed by two identical pictures from Set 2, followed by two identical pictures from Set 3 (the photographs of human faces), and were allowed to study each set for a period of up to 20 seconds. Two days later they were shown the pictures again, first in a brief “reminder” phase in which each previously studied picture was presented on its own, and then for a recognition phase in which the familiar picture from each set was paired with an unfamiliar picture from the same set. Recognition memory was assumed if the infants devoted more looking time to the novel picture in each pair.

Cornell found a novelty preference across all the sets of stimuli that he used. Even though two days had passed since the infants saw the pictures, they remembered those that were familiar and thus preferred to look at the novel pictures in the recognition phase of the experiment. Their recognition memory was not due to the brief reminder cue, as a control group who received the “reminder” phase of the experiment without the initial study phase did not show a novelty response during the recognition test. Given that the stimuli were fairly abstract (except for the faces) and were presented for a relatively short period of time in the initial study phase, their retention over a two-day period is good evidence for well developed recognition memory in young infants.

FIG. 1.1. The stimulus sets used by Cornell (1979) to study recognition memory in infants.
ReprodllCed by permission of Academic Press Inc.

Memory for events

Some striking studies carried out by Clifton, Perris and their colleagues have shown that 6-month-olds can also retain memories for events, and do so over very long time periods. For example, in one such study, 6V2- month-olds were able to retain a memory of a single event that had occurred once until they were 7}/i years of age (Perris, Myers, & Clifton, 1990).

Perris et al. (1990) demonstrated this by bringing some infants who had taken part in an experiment in their laboratory as 6-month-olds back to the laboratory at 2l/i and retesting them. During the infancy experiment the babies had been required to reach both in the dark and in the light for a Big Bird finger puppet that made a rattle noise (the experiment was about the localisation of sounds). The reaching session had taken about 20 minutes. Two years later, the children were brought back to the same laboratory room and met the same female experimenter, who said that they would play some games. She showed them five plastic toys, including the Big Bird puppet, and asked which toy they thought would be part of the game. She then told them that Big Bird made a sound in the game, and asked them to guess which one it was out of a rattle noise, a bell, and a clicker. Finally, the children played a game in the dark, which was to reach accurately to one of five possible locations for the sounding puppet. After five uninstructed dark trials, during which no information about what to do was given, the children were given five more trials in which they were told to “catch the noisy Big Bird in the dark”. A group of control children who had not experienced the procedure as infants were also tested.

Perris et al. found that the experimental group showed little explicit recall of their experiences as infants. They were no more likely than the control group to select Big Bird as the toy who would be part of the game, or to choose the rattle noise over the bell and the clicker. However, they showed a clear degree of implicit recall, as measured by their behaviour during the game in the dark. They were more likely to reach out towards the sound than the children in the control group in the first five trials, and they also reached more accurately. If they were given a reminder of their early experience, by hearing the sound of the rattle for three seconds half an hour before the test in the dark, then they were especially likely to show the reaching behaviour. Again, this was not true of the control group. Finally, the children who had experienced the auditory localisation task as infants were much less likely to become distressed by the darkness during the testing than the children who had not experienced the auditory localisation task as infants. Nine of the latter children (out of 16) asked to leave before completing the uninstructed trials, compared to only two children in the experimental group. Children who had experienced reaching in the dark as infants thus showed evidence of remembering that event two years later in a number of different ways. Similar results were reported in a study by Myers, Clifton, and Clarkson (1987), who showed that children who were almost 3 years old also retained memories of the laboratory and the auditory localisation testing procedures that they had encountered as infants. These children had had 15-19 exposures to the experimental procedures as infants, however, and so their memory is in some sense less surprising than that demonstrated in the experiment by Perris et al.

Memory for causal events

Event memory can also be studied by teaching infants a causal contingency between a response and a reward, as in De Casper and Fifer’s work. This technique of using learned causal relationships between the production of a response and the delivery of a reward has been extended to older infants by Rovee-Collier and her colleagues (e.g. Rovee-Collier et al., 1980). In their pioneering studies, the conditioned response was kicking, and the reward was the activation of an attractive mobile hanging over the infant’s crib. The contingency was that kicking activated the mobile. Activation of the mobile occurred via a ribbon that was tied to the infant’s ankle. As kicking comes naturally to young infants, the kicking response is present whether the mobile is there or not. The important point about Rovee-Collier’s paradigm is that the infant must learn that kicking makes the mobile start to work. Memory for this cause-effect relation was measured by returning the infants to the same crib after some time had passed, and seeing how much they kicked in the presence of the mobile.

For example, in a typical experiment, the infant is visited at home (see Rovee-Collier & Hayne, 1987, for a review). An attractive mobile is erected on the side of their crib, and a second empty mobile stand is also erected (see Fig. 1.2). The ribbon is first tied to this empty stand, to measure the baseline kick rate in the absence of reinforcement with the mobile. After approximately three minutes, the ribbon is attached to the correct mobile stand, and the infant is allowed to kick for about nine minutes for the reward of activating the mobile. The ribbon is then moved back to the empty stand for a final three-minute period. The difference in kick rate between this second three-minute period and the initial baseline period provides a measure of the infant’s short-term retention of the contingency. The infant is then visited a second time some days after the original learning phase, and the ribbon is again tied to the empty stand. Long-term retention of the cause-effect relation is measured by comparing kicking in the absence of reinforcement during this second visit with the original baseline kick rate.

FIG. 1.2. An infant in Rovee- Collier’s causal contingency paradigm (A) during baseline, when kicking cannot activate the mobile, and (B) during acquisition, when the ankle ribbon is attached to the mobile.

Rovee-Collier and her colleagues have found that 3-month-old infants show little forgetting of the mobile contingency over periods ranging from two to eight days. By 14 days, however, forgetting of the contingency appears to be complete. Furthermore, as the time between the learning and test periods increases, the infants forget the specific details of the training mobile (its colours and shapes), and respond as strongly to a novel mobile as to the original. Twenty-four hours after learning, the infants remember the objects on the mobile, and will not respond to mobiles containing more than one novel object. By four days, however, they will respond to a novel five-object mobile. This suggests that infants, like older chi...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Dedication
• Acknowledgements
• Table of Contents
• Series preface
• Foreword
• 1. Cognition in infancy: Basic cognitive processes
• 2. Cognition in infancy: Higher cognitive processes
• 3. Conceptual development
• 4 The development of causal reasoning
• 5. The development of memory
• 6. Mnemonic strategies, metamemory and cognition
• 7. Logical reasoning in childhood
• 8. Piaget's theory of logical development
• 9. The "what" and "why" of children's cognition
• References
• Indices