Less is not more: Further observations on nonlinguistic strategies

In an attempt to clarify the role of nonlinguistic preferences in children's responses to the words more and less, children 3–4 years of age were administered three tasks. Two of these required the child to indicate which of two arrays had more or less items, as instructed; the third task required the child to point to any one of two arrays. Children consistently selected the arrays with more items on all three tasks. The present finding of a response bias necessitates a reinterpretation of earlier studies of more and less. The results are discussed in terms of the full and partial semantics hypotheses as articulated by E. Clark.     

Feature selection and classification: A developmental study

Two hundred and thirteen children between the ages of 4 and 16 sorted 30 complex objects freely into groups. These were either schematic faces, schematic imaginary animals, or histoform patterns and were constructed from 9 independently and continuously varying features, each with 10 levels. The three sets were equivalent in terms of underlying numerical structure. A new method of analysis of the groups formed yielded the following direct measures of subjective organization in the sorting of each child: the number of features used in sorting, the accuracy of sorting, and the number of independent dimensions of classification. Both the material and the analysis of sorting were devised on the assumption that only some of the component features of complex objects are used for classification, while others are ignored. Sorting performance differed markedly both with age and with different types of material. The improvement in sorting ability with age, except for the youngest children, could be attributed to an increase in the number of features used rather than an improvement in the accuracy of use. In contrast, the poor sorting of histoform patterns as opposed to faces and animals was due to a low level of sorting accuracy. The basic results on the development of classification confirmed previous studies, and hence suggest that it is valid to consider feature selection as a basic component of classification.     

Children's selective attention with variation in amount of stimulus exposure

Selective attention in children was measured by means of a central-incidental learning paradigm. Children performed a central task requiring attention to one element in each of several stimuli, after which their incidental learning was assessed by a combination of two tests measuring: (a) recognition of the second, or incidental, element in each stimulus, and (b) association between the incidental and central elements. Principal independent variables were the age of the children (9 vs 12 years) and the amount of exposure time per trial in the central task (6 vs 12 sec). Douling the exposure time increased the incidental as well as the central scores for 9-year-olds, while it increased only the central scores for 12-year-olds. It would appear that younger children maintain a relatively nonselective orientation during an extended exposure period, distributing attention between both relevant and irrelevant stimulus elements, whereas adolescents adopt a more selective approach and concentrate exclusively on task-relevant information. The results are discussed in relation to hypotheses regarding development of selective attention.     

The problem-solving strategies of kindergarten and first-grade children during discrimination learning

Kindergarten and first-grade children (6 and 7 years of age, respectively) were given specially designed discrimination tasks with introtact probes preceding each trial. One group (CON) was given the criterion task without prior training. A second group (LTL) received three pretraining tasks of the same type as the criterion task. A third group (HYP) received the same pretraining tasks, but with explicit instructions designed to teach a simple hypothesis-testing strategy. Several indices, designed to reflect the use of win-stay and lose-shift rules, as well as memory for disconfirmed hypotheses, were computed from the protocols of the criterion task. The indices for Group CON suggested that most of these children were using a guessing strategy that involved quite frequent changes in hypotheses. Moreover, many of these children restricted their hypotheses to the irrelevant cues. The indices for Group LTL revealed a spontaneous use of the hypothesis-testing strategy by nearly half of the children. The results for Group HYP indicated that over four-fifths of these children became highly efficient in the use of the problem-solving strategy.     

Effectiveness of hand overcorrection for topographically similar and dissimilar self-stimulatory behavior

Response contingent hand overcorrection was used to reduce the frequency of self-stimulatory behaviors in four retarded adult males. For two of the subjects, the treated behaviors (hand shaking and nose touching) involved hand movements which were topographically similar to the hand overcorrection procedure. For the other two subjects, behaviors topographically dissimilar to the treatment procedure were treated (inappropriate laughing and head weaving). All four behaviors were decreased in frequency during treatment. However, the hand overcorrection procedure was more effective with the topographically similar behaviors.     

Interpreting inclusion: A contribution to the study of the child's cognitive and linguistic development

Six experiments are reported which examine the young child's ability to compare included and nonincluded sets. Results indicate that with certain forms of task presentation most 3- to 5-year-old children can compare part with whole. Further, errors which occur in inclusion tasks are similar to errors which occur in tasks involving comparison of nonincluded sets. Thus young children can solve inclusion problems, and their customary failure to do so does not arise because the problem requires comparison of a whole with an included part. Employing a distinction between intended tasks (those which the adult wishes the child to complete) and received tasks (those which the child, in fact, completes) the studies indicate how linguistic and perceptual aspects of the presented information may interact with the child's assumptions about the nature of the task to be completed.     

Collaborating careers: The differential effects of race

Male and female black undergraduates enrolled in Introductory Psychology and Human Development courses at a predominantly black university responded to five stories about married black physicians whose total income was greatest, respectively, when the husband cared for the children (Story 1), the wife cared for the children (Story 2), either spouse cared for them (Story 3), the wife earned more than the husband (Story 4), or the husband earned more than the wife (Story 5). In contrast to the results of a study completed at a predominantly white university, black females favored maternal child care even when, as a result, the family income was reduced and had significantly less of a preference for higher relative salary for the wife than did females in the study at a predominantly white university; although black males preferred maternal child care in Story 2 and Story 3, the preference was significantly less than that of males in the study at a predominantly white university. The results were discussed in terms of their relevance to collaborating career patterns among middle-class black families.     

Recovery of the US representation over time during extinction

Four experiments used a conditioned suppression procedure in rats to explore changes in the US representation over time during the course of extinction. They employed two previously reported effects: reinstatement of responding to an extinguished CS by separate US presentation, and the erasure of that effect by interposed nonreinforcement of a second excitatory CS. These effects have been interpreted as enhancing and depressing the US representation, respectively. Experiment 1 found the erasing effect to decrease but still to remain substantial after over a 4-day period, suggesting a partial recovery with time of a deliberately depressed US representation. Experiment 2 implicated this change as a contributor to the phenomenon of spontaneous recovery by showing that recovery to be sensitive to erasure effects. Experiments 3 and 4 found evidence for an interaction between the state of the US representation and the amount of associative change which results from nonreinforcement of an excitatory CS. When the US representation was strong, either because of reinstatement or the passage of time, nonreinforcement of a CS was especially effective in producing associative change. When the US representation had been depressed by erasure, those nonreinforcements produced relatively less associative loss. Moreover, these effects upon associations were reasonably stable in the sense that they left asymptotic differences in the strength of associations after extinction. Together with previous findings, these results point to an important role for the US representation in the performance and learning which occurs during extinction.