Judy S. DeLoache

Dual Representation and Young Children's Use of Scale Models

To use a symbolic object such as a model, map, or picture, one must achieve dual representation; that is, one must mentally represent both the symbol itself and its relation to its referent. The studies reported here confirm predictions derived from this concept. As hypothesized, dual representation was as difficult for 2 1/2-year-olds to achieve with a set of individual objects as it was with an integrated model. Decreasing the physical salience of a scale model (by placing it behind a window) made it easier for 2 1/2-year-old children to treat it as a representation of something other than itself. Conversely, increasing the models salience as an object (by allowing 3-year-old children to manipulate it) made it more difficult to appreciate its symbolic import. The results provide strong support for dual representation.

Becoming symbol-minded

No facet of human development is more crucial than becoming symbol-minded. To participate fully in any society, children have to master the symbol systems that are important in that society. Children today must learn to use more varieties of symbolic media than ever before, so it is even more important to understand the processes involved in symbolic development. Recent research has greatly expanded what we know about early symbol use. We have learned, for example, that infants initially accept a wide range of entities as potential symbols and that young children are often confused about the nature of symbol-referent relations. During the first few years of life, however, children make rapid progress towards becoming competent symbol users.

Early Understanding of the Representational Function of Pictures.

An important function of pictures is the communication of information--a function that has been ignored in research on the development of pictorial perception and comprehension. When are young children first capable of using pictures as a source of information to guide their behavior? The six studies reported here reveal a dramatic developmental change between 24 and 30 months of age in the use of pictorial information about the location of a hidden object. When presented with a picture that showed the location of a hidden toy, 30-month-olds readily retrieved the toy, but 24-month-olds did not. The extremely poor performance of the 24-month-olds was replicated and shown to persist in spite of various modifications made in the task in an effort to improve performance. We conclude that our 24-month-old subjects did not interpret the pictures as representations of current reality. We propose that very young childrens early pictorial experience may predispose them to be overly conservative in interpreting the relation between pictures and their referents.

Manipulatives as symbols: A new perspective on the use of concrete objects to teach mathematics

This article offers a new perspective on the use of concrete objects to teach mathematics. It is commonly assumed that concrete manipulatives are effective because they allow children to perform mathematics without understanding arbitrary, written mathematical symbols. We argue that the sharp distinction between concrete and abstract forms of mathematical expression may not be justified. We believe instead that manipulatives are also symbols; teachers intend for them to stand for or represent a concept or written symbol. Consequently, research on how young children comprehend symbolic relations is relevant to studying their comprehension of manipulatives. We review evidence that many of the problems that children encounter when using manipulatives are very similar to problems that they have using other symbol systems such as scale models. Successful use of manipulatives depends on treating them as symbols rather than as substitutes for symbols. A persistent dilemma for teachers of mathematics concerns how to help children understand

Detecting the Snake in the Grass Attention to Fear-Relevant Stimuli by Adults and Young Children

Snakes are among the most common targets of fears and phobias. In visual detection tasks, adults detect their presence more rapidly than the presence of other kinds of visual stimuli. We report evidence that very young children share this attentional bias. In three experiments, preschool children and adults were asked to find a single target picture among an array of eight distractors. Both the children and the adults detected snakes more rapidly than three types of nonthreatening stimuli (flowers, frogs, and caterpillars). These results provide the first evidence of enhanced visual detection of evolutionarily relevant threat stimuli in young children.

Grasping the Nature of Pictures

The role of experience in the development of pictorial competence has been the center of substantial debate. The four studies presented here help resolve the controversy by systematically documenting and examining manual exploration of depicted objects by infants. We report that 9-month-old infants manually investigate pictures, touching and feeling depicted objects as if they were real objects and even trying to pick them up off the page. The same behavior was observed in babies from two extremely different societies (the United States and the Ivory Coast). This investigation of pictures occurs even though infants can discriminate between real objects and their depictions. By the time infants are 19 months of age, their manual exploration is replaced by pointing at depicted objects. These results indicate that initial uncertainty about the nature of pictures leads infants to investigate them. Through experience, infants begin to acquire a concept of “picture.” This concept includes the fact that a picture has a dual nature (it is both an object and a representation of something other than itself), as well as knowledge about the culturally appropriate use of pictures.

Transfer between Picture Books and the Real World by Very Young Children

Picture book reading is a very common form of interaction between parents and very young children. Here we explore to what extent young children transfer novel information between picture books and the real world. We report that 15- and 18-month-olds can extend newly learned labels both from pictures to objects and from objects to pictures. However, the degree to which they do so is affected by iconicity—how much the objects and pictures resemble one another. The children in these studies more often extended the labels between picture and object when realistic photographs and drawings were involved than less realistic cartoons. These results show that higher levels of perceptual similarity between symbol and referent make the referential relation more transparent, thereby helping children transfer information between them. Thus, the educational function of early picture book interactions may best be served with realistic illustrations. This research was supported by NIH grant HD-25271 to JSD and by NSF grant GA-0440254 to P. A. G. and J. S. D.

Young children's understanding of the correspondence between a scale model and a larger space

Abstract Sensitivity to the correspondence between a scale model and the larger space it represents emerges between 2 1 2 and 3 years of age. In three of the four experiments reported here, young children watched as a miniature toy was hidden somewhere in a scale model of a room. Then the children were asked to retrieve an analogous toy that was hidden in the corresponding place in the room itself. According to the data reported here, success in this and a related task requires that children understand that the model is related to or represents the room. Children below the age of 33 or 34 months are extremely unlikely to become aware of this correspondence, even with extensive instructions and demonstrations. Children a few months older very readily grasp the relation when it is pointed out to them. This research reveals the importance of awareness of the representational relation between a symbol (the model) and its referent (the room) in early symbolization.

Precursors of mnemonic strategies in very young children's memory.

In 4 studies with 18-24-month-old children, evidence was obtained of strategy-like behaviors in a memory-for-location task in which the child had to remember in what natural location a toy had been hidden. The children exhibited behaviors that resemble the mature strategies of rehearsal and monitoring, including talking about the toy or its hiding place and looking or pointing at it during the delay interval. In Experiments 1 and 2, these strategy-like behaviors were engaged in differentially as a function of familiarity, both of the setting in which the task was embedded and of the task itself. Significantly more target behaviors occurred in an unfamiliar than in a familiar setting, and more target behaviors occurred on the first than on the second day of observation. In Experiment 3, when the basic memory task was modified to remove the memory demands from the child, very few of the strategy-like behaviors occurred, indicating that they were indeed memory specific. In the fourth experiment, the rehearsal-like behaviors were shown to be related to subsequent retrieval. We interpret these results as evidence of an early natural propensity to keep alive what must be remembered, a rudimentary and imperfect version of what will later become more elaborate and planful mnemonic strategies.

Superior detection of threat-relevant stimuli in infancy

The ability to quickly detect potential threat is an important survival mechanism for humans and other animals. Past research has established that adults have an attentional bias for the detection of threat-relevant stimuli, including snakes and spiders as well as angry human faces. Recent studies have documented that preschool children also detect the presence of threatening stimuli more quickly than various non-threatening stimuli. Here we report the first evidence that this attentional bias is present even in infancy. In two experiments, 8- to 14-month-old infants responded more rapidly to snakes than to flowers and more rapidly to angry than to happy faces. These data provide the first evidence of enhanced visual detection of threat-relevant stimuli in infants and hence offer especially strong support for the existence of a general bias for the detection of threat in humans.