Categorization and abstraction abilities in 3-year-old children: a comparison with monkey data

Three-year-old children were tested on three categorization tasks of increasing levels of abstraction (used with adult baboons in an earlier study): the first was a conceptual categorization task (food vs toys), the second a perceptual matching task (same vs different objects), and the third a relational matching task in which the children had to sort pairs according to whether or not the two items belonged to the same or different categories. The children were tested using two different procedures, the first a replication of the procedure used with the baboons (pulling one rope for a category or a relationship between two objects, and another rope for the other category or relationship), the second a task based upon childrens prior experiences with sorting objects (putting in the same box objects belonging to the same category or a pair of objects exemplifying the same relation). The children were able to solve the first task (conceptual categorization) when tested with the sorting into boxes procedure, and the second task (perceptual matching) when tested with both procedures. The children were able to master the third task (relational matching) only when the rules were clearly explained to them, but not when they could only watch sorting examples. In fact, the relational matching task without explanation requires analogy abilities that do not seem to be fully developed at 3 years of age. The discrepancies in performances between children tested with the two procedures, with the task explained or not, and the discrepancies observed between children and baboons are discussed in relation to differences between species and/or problem-solving strategies.     

The adaptive nature of children's overestimation in a strategic memory task

Kindergarten, first-, and third-grade children were given a multitrial sort-recall task with different items on each trial. Children were asked to predict how many items they would recall prior to each trial. We classified children into high- and low-overestimation groups based on their prediction accuracy on the first two trials and assessed changes in recall and strategy use over trials (trials 4/5 minus trials 1/2). Following predictions, at all grades, children in the high-overestimation group showed greater gains (or fewer losses) in recall than children in the low-overestimation group. Differences in strategy use over trials were generally nonsignificant. The results were interpreted as reflecting the adaptive nature of children's overestimation of their cognitive abilities.     

Discovery and maintenance of the many‐to‐one counting strategy in 4‐year‐olds: A microgenetic study

This study investigated the development of the many‐to‐one counting strategy in 4‐ year‐old children. In the first experiment, 52 children participated. Their development with respect to two kinds of tasks, a hidden‐items task and a needed‐items task, was studied over four sessions. Children (n = 28) who accurately used the many‐to‐one strategy in Session 4 also participated in the second experiment. These children were presented with more difficult hidden‐ and needed‐items tasks. It was found that children often produced the strategy for the first time on tasks with relatively few items. Most children then kept producing it, even if they initially did not obtain much profit from its use because of counting errors. Increasing task difficulty resulted in children making more counting errors or reverting to invalid strategies depending on the nature of the new task.     

Development of strategies for recalling letter sequences

Kindergarten, second-grade, and fourth-grade children (6, 8, and 10 years of age, respectively) were asked to recall letter sequences on a task that required the use of: (a) a verbal strategy; (b) a positional strategy; or (c) either strategy. Additional trials, allowing either strategy, were interspersed among those requiring a verbal or positional strategy; strategy use was determined from performance on these interspersed trials. The results show that children at all grade levels attempted to use a task-appropriate strategy. Performance on the verbal task showed a more marked developmental increase than did performance on the positional task. A second experiment replicated the first with the interspersed trials removed. A third experiment was designed to determine whether letter names interfered with older children's efficient use of a positional strategy. Even with this source of interference removed, the developmental pattern of Experiments 1 and 2 was replicated. There was a Sex by Condition interaction in Experiments 2 and 3 which showed that males do better in the condition requiring a positional strategy, and females do better in the condition requiring a verbal strategy.     

Age differences in the capacity demands of a strategy among spontaneously strategic children.

This study examined whether spontaneously strategic children from two age groups differed in the capacity required to execute a strategy. The strategic behavior of younger (grades K and 1) and older (grades 4 and 5) children (N = 104) was assessed on a selective memory task. Children selected objects to view from a larger pool of objects. The most mature strategy (i.e., selectivity) involves opening doors that reveal objects to be remembered and not opening those that do not. In a dual-task procedure in a second session, children performed a finger tapping task simultaneously with the selective strategy. The reduction of rate of finger tapping from the finger tapping baseline to the dual-task trials provided an assessment of the capacity required to execute the strategy. A control group followed the same procedure, but with a simpler door opening selective strategy. A significant age difference in the capacity required for the strategy, even among spontaneously strategic children, suggested that there is further development of strategies even after children spontaneously produce them. Results were discussed in terms of increased strategy effectiveness during development.     

Transitive choices by a simple, fully connected, backpropagation neural network: implications for the comparative study of transitive inference.

In search of the minimal requirements for transitive reasoning, a simple neural network was trained and tested on the non-verbal version of the conventional "five-term-series task" – a paradigm used with human adults, children and a variety of non-human species. The transitive performance of the network was analogous in several aspects to that reported for children and animals. The three effects usually associated with transitive choices i.e. "symbolic distance", "lexical marking" and "end-anchor", were also clearly shown by the neural network. In a second experiment, where the training conditions were manipulated, the network failed to match the behavioural pattern reported for human adults in the test following an ordered presentation of the premises. However, it mimicked young children's performance when tested with a novel comparison term. Although we do not intend to suggest a new model of transitive inference, we conclude, in line with other authors, that a simple error-correcting rule can generate transitive behaviour similar to the choice pattern of children and animals in the binary form of the five-term-series task without requiring high-order logical or paralogical abilities. The analysis of the training history and of the final internal structure of the network reveals the associative strategy employed. However, our results indicate that the scope of the associative strategy used by the network might be limited. The extent to which the conventional five-term-series task, in absence of appropriate manipulations of training and testing conditions, is suitable to detect cognitive differences across species is also discussed on the basis of our results. Accepted after revision: 29 May 2001 Electronic Publication     

Transfer of a memorization strategy in 10-year-old children: study of individual differences]

The spontaneous or induced use of an organization strategy is examined on free recall tasks with 10-year-old children classified as rather global or rather analytical at the Group Embedded Figures test. The experimental procedure include three successive and identical tests followed by two deffered tasks, one requiring a transfer of maintenance and the other a transfer of generalization. The experimental group, who attended a simple illustration of the organization strategy before the second test, applied the strategy quickly and successfully: for these subjects, one does not note differences between global or analytical subjects in the recall performance; however, the global subjects modify their study strategy of the material on the generalization task. For the control group, global or analytical subjects have a different evolution for the performance and the strategic attitude according to the procedure. The analytical subjects are different from global subjects on the generalization task.     

Conditions under which children experience inhibitory difficulty with a "button-press" go/no-go task

Go/no-go tasks seem to provide a simple marker of inhibitory development in young children. Children are told to respond to one stimulus on go trials but to make no response to another stimulus on no-go trials; responding on no-go trials is assumed to reflect a failure to inhibit the go response. However, there is evidence to suggest that a type of go/no-go task, which we call the "button-press" task, does not require inhibition. We investigated the conditions under which young children (M=3 years 6 months, N=120) experience inhibitory difficulty with this type of task. The data suggest that the speed of stimulus presentation is crucial and that other studies using this type of task have presented the stimuli too briefly. The importance of establishing the inhibitory credentials of a task before it is used as a marker of inhibitory control is emphasized.     

Controlled and automatic processing during mental rotation

In two experiments, 9- and 10-year-olds and adults were tested on a mental rotation task in which they judged whether stimuli presented in different orientations were letters or mirror-images of letters. The mental rotation task was performed alone on 48 trials and concurrently with a memory task on 48 additional trials. The concurrent memory task in Experiment 1 was recalling digits; in Experiment 2, recalling positions in a matrix. The key result was that the slope of the function relating response time to stimulus orientation was the same when the mental rotation task was performed alone and when performed concurrently with the memory task. This result is interpreted as showing that mental rotation is an automatic process for both children and adults.     

Children's memory for new songs: integration or independent storage of words and tunes?

The present study investigated how young children encode a song in memory, specifically, whether they integrate or store independently in memory the text and the tune of a song. Preschool children and, for purposes of comparison, adults, each participated in two test sessions: in one they were presented three novel tunes each with rhyming text and in the other they heard the same three tunes but with nonrhyming text. Following this familiarization phase they received a recognition test. On each trial, they heard one of five types of songs; the original song, a completely new song (new words, new tune), a mismatch of the tune of one song with the words of another, old words with a new tune, and new words with an old tune. The subject's task was to decide if each test song was "exactly the same," "somewhat the same," or "not at all the same" as any one of the three original songs. At both ages the proportion of "same" responses was significantly greater for the original than mismatch songs, indicating that listeners were more likely to remember the exact pairing of text and tune than to retain the components independently. However, integration was significantly greater for adults than children. At both ages, for songs judged as similar to the original songs, the words more often than the tune proved to be the most salient feature, particularly for children. There were no significant effects of rhyme on performance at either age. The results are discussed in terms of Serafine, Crowder, and Repp's (1984) hypothesis that one integrates the tune and text of a song in memory, rather than storing components separately.     

Relative sensitivity of the mutual exclusivity and novel-name-nameless category assumptions

The mutual exclusivity (ME) assumption states that children affix a novel label to only one unfamiliar object, while the novel-name-nameless category (N3C) assumption states that children affix a novel label to multiple unfamiliar objects. To compare the relative sensitivity of the two assumptions, two types of tasks, with two trials in each, were given to 5-year-olds. In the first trial of each task, all children selected only the unfamiliar object for a novel label, which was consistent with the ME assumption. For the task which did not have the same unfamiliar object in the two trials, 94% of the children selected the object with the same shape but black-white reversed image in the second trial, which was consistent with the N3C assumption. For the task which had the same unfamiliar object in the two trials, 43% of the children selected the same object in the second trial, which was consistent with the ME assumption, and 48% of them selected the object with the same shape but reversed image, which was consistent with the N3C assumption. The findings suggest that the ME and N3C assumptions can be flexibly applied to children's word learning.     

Spontaneous private speech and performance on a delayed match-to-sample task

Spontaneous private speech samples were obtained from 65 kindergarten children (mean age 70.3 months) from one suburban (n = 36) and one city (n = 29) school as they worked alone on a delayed match-to-sample (DMS) task with three levels of difficulty (2, 10, and 30 sec delays). As expected increases in DMS delay intervals produced decreased performance and increases in private speech. The expected increased positive relationship between task relevant private speech and performance for longer delays was found in city children but not suburban children. Since mean IQ scores were significantly different for the two groups this variable was further examined in post hoc analyses and discussed along with socio-economic status as possible explanations for the observed school-sample differences. A within-subject comparison for all children showed the percentage of speaking trials correct at 30-sec delay to be significantly greater than the percentage of nonspeaking trials correct. The effect of one experimenter modeled trial on a subsequent 10 trials at 30-sec delay was to increase speech and performance and to show a stronger relationship between speech and performance than for premodeling trials. These exploratory findings with a relatively simple two color matching task suggest further explorations of spontaneous private speech as a way of studying internalization of self regulatory cognitive strategies.     

Overcoming spontaneous patterns of coordination during the acquisition of a complex balancing task.

Learning in complex tasks is usually conceived as the problem of mastering the multiple and redundant degrees of freedom of the system. To reduce control requirements, two different strategies are conceivable. The first one consists of a "freezing-freeing" process for most articular joints to reduce the number of active biomechanical degrees of freedom to be managed. The second strategy consists of introducing rigid couplings between the oscillators building the system. In this case, learning implies the dissolution of initial couplings and the emergence of new, more task-specific couplings. The goal of our study was to analyze the spontaneous coordination of beginners and its development in a complex balancing task on a stabilometer, and to examine the emergence of these two strategies. Our results showed that beginners were characterized by strong couplings between the joints of the lower limbs. During learning, new and more task-specific couplings emerged that reflected a new organization of the trunk and a decoupling of some joints of the lower limbs that were initially coupled during the first few trials.     

Area-matching strategies used by young children

Across three studies, conditions were varied under which children aged 4–5 years matched the area of a rectangle with a given width (or height) to that of a square. In the first study, subjects observed the rectangle being changed in height from trial to trial and had access to their immediately preceding response. Under these conditions, rectangle width (the dimension under subject control) was a linear decreasing function of rectangle height. This function was interpreted as evidence for a hypothetical addition/subtraction strategy for maintaining equality in area between the comparison rectangle and the standard square. As a test of this hypothesis, in a second experiment the subjects were denied access to their immediately previous response, and in a third study they were also unable to observe the rectangle as it was altered by the experimenter between trials. The purpose of these changes was to remove the information necessary for readily implementing an addition/subtraction strategy. In both studies, area matches seemed to be based on a side-matching strategy, such that subjects matched one dimension of the rectangle to one side of the standard square. It was suggested that young children use different cues or strategies with different variants of the matching task because they do not possess a fixed, specific concept of area.     

6岁儿童的类别学习能力:类别表征、注意和分类策略

探讨了6岁儿童的类别学习能力、类别表征和分类策略。62名儿童参加了实验,实验1采用了"5/4模型"类别结构,实验2采用了"3/3类别结构"。结果发现:6岁儿童已经具备了一定的类别学习能力;相对于原型表征,6岁儿童更倾向于进行样例表征;6岁儿童在注意上具有定位在高典型性特征维度上的能力,但不具备定位在区分性特征维度上的能力;在类别学习策略上主要采用单维度分类策略和规则加例外的分类策略。     

A Longitudinal Study of Semantic Grouping Strategy Use in 6–11-Year-Old Children: Investigating Developmental Phases,the Role of Working Memory,and Strategy Transfer

This two-cohort longitudinal study on the development of the semantic grouping strategy had three goals. First, the authors examined if 6–7-year-olds are nonstrategic before becoming strategic after prompting at 8–9 years of age, and if 8–9-year-olds are prompted strategic before spontaneous strategy use at 10–11 years of age. Children 6–7 and 8–9 years old performed two sort-recall tasks (one without and one with a grouping prompt) at two time points separated 1.5 years from each other. Second, the authors investigated whether short-term or working memory capacity at time point 1 predicted recall in children who did or did not use the semantic grouping strategy 1.5 years later. Third, the authors investigated whether prompted strategic children and children who used the strategy spontaneously differed in strategy transfer to a new task. Developmental results confirmed previous cross-sectional results, but in a longitudinal two-cohort study 6–7-year-olds were nonstrategic, and became prompted strategic around 8–9 years of age, followed by spontaneous strategy use at age 10–11 years. The authors found that memory capacity was not predictive of later use of the strategy. New findings were that prompted strategic children were as equally able as spontaneously strategic children to transfer the strategy to a new task, albeit with smaller recall benefits.     

Processing speed in the 1st year of life: a longitudinal study of preterm and full-term infants

Processing speed was assessed at 5, 7, and 12 months in full-term and preterm infants (birth-weight < 1,750 g). Speed was gauged directly in a new task by presenting infants with a series of paired faces, one that remained the same across trials and one that changed; trials continued until infants showed a consistent novelty preference. At all ages, preterms required about 20% more trials and 30% more time than full-terms to reach criterion. Among preterms, slower processing was associated with greater medical risk (e.g., respiratory distress syndrome). Developmental trajectories for speed (and attention) were similar for both groups. Thus, the deficits in processing speed previously found for preterms in childhood are already present in the 1st year of life.     

Emergence of drawing devices for total and partial occlusion: a longitudinal study

The developmental emergence of two drawing devices was investigated in young children: the use of omission (ie not drawing any of a hidden object) to depict total occlusion and the use of hidden line elimination (HLE, ie deleting only that part of an object that is hidden from view) to depict partial occlusion in a three-dimensional scene. Three groups of school children (5, 6, and 7 years old) were tested individually with two tasks four times over a 2-year period. One task called for the omission device (to draw a cup with its handle not in view) and the other for the HLE device (to draw one ball behind and partially occluded by another). The stimuli in each task were presented in pairs, with one member of the pair showing the occluded scene and the other a canonical or not-occluded scene. Changes in the strategies used by the children to indicate the visual differences within the pairs were recorded over the four testing sessions. Children were found to use the omission device more readily with the cup task than the HLE device with the ball task. There was an age-related trend in every task in the use of the drawing device appropriate to that task. For those who did not use the drawing device appropriate for a perspective drawing, there was a tendency for each age group to favour a particular strategy for representation. The advantage of using a longitudinal design to chart the developmental trend of the emergence of these two drawing devices is discussed.