Is there a developmental trend from integrality to separability in perception?

Some previous literature suggests that young children perceive in an integral, holistic fashion stimuli that older children perceive in a separable, dimensionalized mode. A prediction from a strong form of this position is that younger children actually may perform more rapidly a speeded classification task that requires “condensation” than a task that requires “filtering” (if the similarity relations among the wholes favor the former task). Older children should be able to take advantage of the simple unidimensional basis of the filtering task and thus accomplish it much more rapidly than the condensation task. The results are only partially in accord with the predictions. Kindergarteners (5 years of age), on size-and-brightness stimuli, show no speed advantage on either task, while second (8 years) and fifth (11 years) graders clearly show more rapid filtering. Therefore, the developmental hypothesis is in need of some revision and elaboration. Some stimuli are less separable for younger than for older children, but even five year olds can access their dimensional structure under some conditions.     

Control of children's observing responses by information feedback during visual discrimination learning

Four experiments examined the control of observing responses by information feedback during visual discrimination learning. Second-grade children participated in Experiment 1; kindergarten, second-, and fifth-grade children were subjects in Experiments 2 and 3, and grade 5 and adult subjects were tested in Experiment 4. In order to view the stimuli, subjects in Experiments 1, 2, and 3 activated lights in viewing boxes; in Experiment 4, stimulus fixations were measured using a corneal reflection technique. Fifth graders and adults observed the discriminative stimuli for longer times on trials following negative feedback than on trials following positive feedback; in contrast, kindergartener's observing was not affected by type of feedback. Second graders showed smaller and less reliable reactions to type of feedback than did older subjects. These results support the view that visual observing is controlled by cognitive processes associated with hypothesis testing.     

The generality of transfer: Effects of age and similarity of training and transfer tasks

Two experiments were conducted investigating the extent to which transfer of training would take place. The Ss were trained to attend to a particular dimension (color or form) of a set of stimuli and were then presented with a transfer problem. For half the Ss the transfer problem was an intradimensional (ID) shift, and for the remaining half an extradimensional (ED) shift, with the ID-ED difference then being used as an index of the magnitude of transfer. Previous data had indicated that preschool and kindergarten children did not effectively transfer learned attention responses from one task to another if the formats of the two problems were different. Experiment I investigated the hypothesis that older children would show broader patterns of transfer. However, the patterns obtained with second and fifth graders were extremely similar to those obtained with younger children. In Exp. II, it was found that transfer did take place across different task formats if the stimuli remained the same from training to transfer. The data were discussed in terms of the role of contextual cues, or context markers, in the origical acquisition of information and the subsequent transfer (use) of that information.     

Dimensional separability or flexibility of attention? Age trends in perceiving configural stimuli

The hypothesis that perceptual development proceeds from less to greater dimensional separability was tested by giving a speeded classification task to first and fouth graders. In Experiment 1, children sorted line drawings of a cartoon figure into two piles according to his eyes (open or closed) or his mouth (smiling or frowning). First graders exhibited the pattern characteristic of integral dimensions: An interference effect was found when dimensions were combined orthogonally and a facilitation effect when dimensions were correlated, relative to a condition in which only one dimension varied. Fourth graders exhibited an optional separable pattern: There was facilitation in the correlated condition but no interference in the orthogonal condition. These results support the hypothesis that development proceeds toward greater flexibility of attention rather than simply toward increasing separability. A flexible field hypothesis of visual attention was suggested to explain how older children can exercise such optional separability. This hypothesis correctly predicted the asymmetrical relation between dimensions found in Experiments 2 and 3: For both first and fourth graders, the eyes of a cartoon figure (open or closed) and his location (right or left) were nonseparable when the eyes were relevant and separable (or optional separable) when location was relevant.     

When is a question not answered? The understanding of young children of utterances violating or conforming to the rules of conversational sequencing

Knowledge of the conventional rules of conversational sequencing enables a speaker or listener to evaluate the pragmatic use of an utterance. This study explored young children's ability to discriminate among utterances that violated or conformed to these rules (Experiment 1), and ability to explain rule violations (Experiment 2). In both experiments children were read short episodes containing utterances that conformed to the rules in that the utterances were used appropriately in the episodic context of utterance, or utterances that violated the conversational rules of contingency, relevance, or informativeness. In Experiment 1, kindergarten, and first- and second-grade children (5, 6, and 7 years of age) were asked to discriminate among the conforming and rule violating utterances by assigning each utterance to one of two female conventional and unconventional speakers. The results showed that the first and second graders, but not the kindergarten children, generally discriminated among the utterances. In Experiment 2, first and third graders (6 and 8 years of age) were asked to explain the rule violations. The results showed that only the third graders consistently generated correct explanations. These results suggest that children can use the rules of conversational sequencing to evaluate the need for an inference to the speaker's intent in deliberately violating a rule by 6 or 7 years of age, but do not correctly infer that intent until they are 8 or 9 years old.     

Habituation in children within a behavior suppression paradigm

Using an instrumental response suppression paradigm, Experiment 1 demonstrated habituation and long-term retention of habituation to a tone stimulus in third-grade children, but specificity of habituation was not obtained when a new tone stimulus was presented. In Experiment 2 first graders showed specificity of habituation to auditory stimuli on the response suppression measure whereas fifth graders did not. However, both age groups evidenced specificity when a skin conductance measure was employed. In addition, specificity of habituation was not affected by amount of training at either age level. Experiment 3 demonstrated specificity of habituation in fifth graders on the response suppression measure when a cross-modality stimulus change was introduced. Implications of these data for analyses of habituation and traditional learning are discussed.     

Memories of Morocco: The influence of age,schooling, and environment on memory

To what extent are models of memory general, in that they may be applied to children or to other cultural groups? In an attempt to answer this question, two experiments were undertaken in Morocco to investigate various cultural and experiential antecedents to memory development. A total of 384 children and young adults, ranging in age from 6 to 22 years, were tested in a design that contrasted schooled and nonschooled children in urban and rural environments. Three additional groups of subjects—Koranic students, Moroccan rug sellers, and University of Michigan students—were also studied because it was hypothesized that each might have particular “culture-specific” memory skills as a function of previous experience.A serial short-term recall task was used in Experiment I. Results showed that the recency effect or short-term store was generally invariant with age or experience. Control processes appeared to be a function of age, but only when coupled with schooling, and, to a lesser extent, urban environment. In Experiment II, a continuous recognition memory task was given with black and white photographs of Oriental rugs as stimuli. Forgetting rates were generally invariant with age and experience, while the acquisition parameter seemed to vary as a function of specific cultural experiences. Data from the three additional groups were useful in supporting the hypothesis of culture-specific memory skills.From Experiments I and II, and previous research, it was hypothesized that structural features of memory (e.g., short-term store and invariant forgetting rates) may be universal, while control processes or mnemonics in memory are probably culture-specific, or a function of a variety of experiential and cultural factors that surround the growing child.     

Perceptual sensitivity to dimensional and similarity relations in free and rule-governed classifications

Two experiments were conducted to investigate the perceptual primacy of dimensional and similarity relations in the stimulus classifications of younger and older subjects. In Experiment 1, 4- and 10-year-olds were given free classifications in which they could group stimuli according to overall similarity or identities in size, color, or orientation. Both age groups classified stimuli most frequently according to identities on separate dimensions. In Experiment 2, 4-year-olds and adults were given free classifications followed by rule-governed classifications which required them to group stimuli according to specific relations. In the free classifications, a majority of subjects in both age groups classified the stimuli most frequently according to identities on separate dimensions. In the rule-governed classifications, both age groups were more accurate when a single separate relation was required for solution than when overall similarity was required. These results support a differential-sensitivity view of perceptual development, which asserts that individuals at all ages primarily perceive and use separate relations.     

Retrieval variability: The inefficient use of retrieval cues by young children

The hypothesis of this study is that the inefficient use of retrieval cues by young children is due to retrieval variability: the variable encoding of semantic information in cue stimuli at input and retrieval and the inability to reinterpret cue information to ensure cue-trace compatibility. The critical manipulations involved the use of semantic orienting questions at both input and retrieval. Second and fourth graders and college adults were given moderately associated word pairs (Knife-Axe). Encoding was constrained or free between groups at both input and retrieval. The retrieval questions biased the Same interpretation of the cue as at input (weapon), a uniquely Different interpretation (utensil), or an inappropriate Negative interpretation. Both cued recall and recognition of the target items was tested. The results showed systematic developmental increases both in the distinctiveness of the semantic encoding of stimulus information, and in the ability to reinterpret cue information to ensure cue-trace compatibility. The second graders encoded more variably than the older subjects, and were less able to shift from an incompatible encoding of cue information.     

Reasoning about conditional sentences: development of understanding of cues to quantification

The previous literature has reported that when children are asked to judge the truth or falsity of universally quantified conditional sentences of the form If a thing is P then it is Q they typically give responses, e.g., responding "true" whenever there is a case of P and Q even if there are also cases of P and not-Q. Three experiments are reported that address possible sources of this error. Experiment 1 shows that the error survives on sentences that refer to particular things as well as to things of a particular kind, and further shows that articulating the necessity of the consequent (... then it has to be Q) eliminates the error for adults and reduces it for fifth graders, although it does not affect second grade performance. Experiment 2 shows that for second and fifth graders the error survives to problems that are not universally quantified and for second graders to problems that are not conditionals although are otherwise structurally similar. Experiment 3 compares various verbal formulations of such universally quantified conditionals: Second and fifth graders do not make the error when the quantification is expressed with the surface structure that makes its universality most explicit (all things ...); the error tendency is greatest when the indefinite article is used (if a thing ...); and formulations using any fall in between. We argue that such erroneous evaluations of universally quantified conditionals have more to do with the quantificational aspect than the conditional aspect of the problems; children interpret the indefinite article as existential, although they resist the error when the cue to universal quantification is completely clear. The error appears to result more from the surface-structure form of the stimuli than from an inability of children to appreciate the logic of universally quantified conditionals.     

Differences in the search rate of children and adults in short-term memory

When people recognize a test item as belonging or not belonging to a previously presented set, recognition latency increases with the number of items in the set. Although some evidence suggests otherwise, it is currently held that the rate of this increase is the same for children and adults. In contrast, the present experiments indicated a much slower search rate for second graders (mean age = 7.33 years) than for seventh (mean age = 12.50 years) and twelfth graders (mean age = 17.25 years). Moreover, search rate for second graders was invariant under instructions which did or did not emphasize speed and with presentation of the memory set in either the auditory or visual modality. Experiment II showed that the slow search rate for children was not due to differences in encoding between children and adults.     

The Development of Attribute Dominance in the Knowledge Base

Two cuing, free-recall studies were conducted to test Bach and Underwood's (1970) hypothesis that acoustic encoding is dominant among second graders and semantic encoding is dominant among sixth graders. When retrieval cues were presented with to-be-remembered items at both input and output (Experiment 1), and when cues were presented only at output (Experiment 2), semantic cues were more efficient in elevating recall than were acoustic cues for both second and sixth graders. When these and other results generally found using recognition, sorting, incidental learning, and free-recall experimental designs are compared, it seems plausible that item presentation and memory-testing formats interact with age, and that these factors account for the different patterns of attribute dominance found in the literature. The knowledge base cannot be understood by focusing on either subject or task analyses, but only by focusing on interactions between subject and task variables as they change over time. The educational implications for young grade-school children are discussed.     

Developmental verbal control of behavior: Implications for self-instructional training

Kindergarten, first-grade, and second-grade children (5, 6, and 7 years of age, respectively) performed a Luria-type verbal control task in which motor responses are initiated to positive stimuli and inhibited to negative stimuli. The task was performed by motor responding only and verbal self-directed motor responding, with these conditions reversed in sequence for one half of each grade group. Although motor responding and verbal-motor responding by the two younger groups were generally poor, their performance equalled that of the second graders when the verbalizing condition followed the silent, motor-only condition. For these children, verbalizing appeared to constitute a second task which interfered with motor responding. Prior practice on motor-only responding, however, facilitated subsequent, concurrent performance of the two tasks. No interference or practice effects were found for the second graders. The results suggested that self-instructional training programs are likely to be successful when adequate verbal-motor coordination can be assumed or when the motor response is within the child's repertoire.     

Developmental reversal in classification accuracy due to an increase with age in orientation-free judgments.

A complete developmental reversal in accuracy was obtained in Experiment I in which third graders, sixth graders, and adults judged the class membership of patterns presented in a same-different task. An examination of the task requirements and pattern classes employed led to the hypothesis that the reversal in accuracy resulted from an increase with age in orientation-free judgments. The results of Experiment II, in which adults were told to not rotate the patterns, and Experiment III, which was a replication of Experiment I using symmetric rather than areally skewed pattern classes, provided confirmation for that hypothesis.     

The effects of encoding distinctiveness on retrieval variability in children and adults

To what extent are developmental differences in encoding distinctiveness responsible for differences in retrieval variability? This study examined this question by comparing the effects of different kinds of encoding distinctiveness on the ability of children and adults to reinstate the input environment at retrieval. The critical manipulations involved the use of semantic orienting questions at both encoding and retrieval. Second and fourth (Experiment 1) or fifth (Experiment 2) graders and college adults were given moderately associated word pairs (Knife-Axe) at input. Encoding was free or constrained at input and retrieval. The retrieval questions biased the Same interpretation of the cue as at input (weapon), a uniquely Different interpretation (utensil), or an inappropriate Negative interpretation. Encoding distinctiveness was varied by crossing these manipulations with either picture or word input (Experiment 1) or general or distinctive orienting questions (Experiment 2). The results suggested that encoding distinctiveness and retrieval variability contribute independently to developmental differences in recall.     

Illusory correlation and the maintenance of sex role stereotypes in children

The present work tested the hypothesis that children would perceive illusory correlations leading to greater recall of events that confirm rather than disconfirm sex-stereotypic beliefs. In the study, 33 second graders and 34 fourth graders were shown slides of adult males and females engaged in traditional sex role activities, nontraditional activities, and gender-neutral activities. Frequency judgments of the occurrence of each Stimulus Type x Stimulus Sex category served as the dependent measure. In actuality there was no correlation between gender and activity type in the stimulus set. As expected, both age groups perceived illusory correlations, giving the highest frequency estimates to traditional stimuli and the lowest frequency estimates to nontraditional stimuli. Individual differences in level of stereotyped attitudes had no effect on this cognitive bias. Results are discussed in terms of gender schema theory and the maintenance of sex role stereotypes.This research was supported by grants to the first author from the University of Pittsburgh at Johnstown and the Pennsylvania State System of Higher Education. We wish to express our appreciation to Lynn Liben and Margaret Signorella for the use of their stimuli. We would also like to thank the administrators, teachers, and students whose cooperation made the project possible. An earlier version of this paper was presented at the 59th annual meeting of the Eastern Psychological Association, Buffalo, NY, April 1988.     

The development of attribute dominance in the knowledge base

Two cuing, free-recall studies were conducted to test Bach and Underwood's (1970) hypothesis that acoustic encoding is dominant among second graders and semantic encoding is dominant among sixth graders. When retrieval cues were presented with to-be-remembered items at both input and output (Experiment 1), and when cues were presented only at output (Experiment 2), semantic cues were more efficient in elevating recall than were acoustic cues for both second and sixth graders. When these and other results generally found using recognition, sorting, incidental learning, and free-recall experimental designs are compared, it seems plausible that item presentation and memory-testing formats interact with age, and that these factors account for the different patterns of attribute dominance found in the literature. The knowledge base cannot be understood by focusing on either subject or task analyses, but only by focusing on interactions between subject and task variables as they change over time. The educational implications for young grade-school children are discussed.     

Mental rotation performance in primary school age children: Are there gender differences in chronometric tests?

In contrast to the well documented male advantage in psychometric mental rotation tests, gender differences in chronometric experimental designs are still under dispute. Therefore, a systematic investigation of gender differences in mental rotation performance in primary-school children is presented in this paper. A chronometric mental rotation task was used to test 449 second and fourth graders. The children were tested in three separate groups each with different stimulus material (animal drawings, letters, or cube figures). The results show that chronometric mental rotation tasks with cube figures – even rotated in picture plane only – were too difficult for children in both age groups. Further analyses with animal drawings and letters as stimuli revealed an overall gender difference in response time (RT) favoring males, an increasing RT with increasing angular disparity for all children, and faster RTs for fourth graders compared to second graders. This is the first study which has shown consistent gender differences in chronometric mental rotation with primary school aged children regarding reaction time and accuracy while considering appropriate stimuli.     

Some theorems in haploscopic vision

Three formal hypotheses are specified concerning the combination of neural signals from the two eyes. The hypotheses are (1) that a large uniform light presented to the opposite eye has no effect (independence), (2) that all information from one eye relevant to a given percept (for example, brightness) is encoded by a single neural signal (isolation), and (3) the mutually exclusive and exhaustive alternative to isolation (interaction). Though independence or isolation often has been claimed or simply assumed to hold, these hypotheses imply specific empirical relationships. These relationships are derived for brightness and for equilibrium colors. In addition, one model consistent with the interaction hypothesis is developed. The isolation hypothesis is important for generalizing results from monocular experiments to normal binocular vision. If it is false, monocular results can reflect a combination of one eye's neural signals that never occurs with binocular stimuli.