Pathological left-handedness and familial sinistrality in relation to degree of mental retardation

The relationship between personal and familial hand preference and mental retardation was examined. Six unimanual tasks were performed by 232 subjects within four mental retardation severity groups. Family handedness histories were obtained. Right hand preference varied inversely with severity of mental retardation. The handedness of mentally retarded groups at the different functional levels paralleled, but tended much more to the sinistral, than that of the corresponding parent groups. The parent-proband handedness correlations were largely insignificant, especially in lower functioning groups. The findings support both pathological left-handedness theory and an association between brain damage causing mental retardation and familial sinistrality.     

The relationship of participation in school activities to abilities and interests in a high school student sample

Participation in school activities is hypothesized to be related to the multiple abilities and interests of high school students. The Ball Aptitude Battery (yielding 14 ability scores), Holland's Vocational Preference Inventory, and a biographical information blank (to obtain information about participation in 53 extracurricular activities) were administered to over 900 high school seniors of both sexes. Correlational and multiple regression analyses showed different patterns of activity participation to be related to different abilities and interests. The degree of relationship was generally low, generally higher for the males than for the females, and higher for interests than for abilities. Activity correlates of abilities differed for the sexes, but activity correlates of interests tended to be similar. This suggests that the same ability can result from differential participation in activities, but the same interest develops from similar activities.     

Specificity in contrast effects: Judgments of psychopathology

Three experiments were conducted to explore the specificity of the contrast effect in judgments of psychopathology. In the first two studies, respondents initially attempted to infer whether each item in a series of behavior samples (vocabulary definitions in one study, handwriting samples in the second) came from a schizophrenic or a nonschizophrenic patient. Some respondents were presented with highly pathological samples in this induction series, while others were presented with relatively nonpathological samples. These divergent experiences led to marked contrast effects in evaluating test stimuli from the same behavioral domain (e.g., additional vocabulary definitions), but had significantly less impact on the respondent's reactions to stimuli from a different domain (e.g., handwriting samples). A third experiment yielded similar results, using a paired-comparison methodology. In this study subjects first judged a series of high- vs low-pathology definitions. They were then presented with a series of matched stimulus pairs, each including one vocabulary definition and one hand-writing sample. Respondents were to indicate the member of each pair that seemed more indicative of schizophrenia. People assigned to the high-pathology induction group typically chose the handwriting samples as being more indicative of schizophrenia, compared with respondents who were assigned to the low-pathology conditions. These results were interpreted as supporting a representational (perceptual) theory of contrast.     

Frequency judgment accuracy as a function of age and school achievement (learning disabled versus non-learning-disabled) patterns

The accuracy of children's judgments of relative situational frequency was examined in two experiments. In Experiment 1 children with normal achievement in Grades 2 and 3 were compared with such children in Grades K and 5, as well as with three groups of low-achieving children in Grades 2 and 3. These latter groups consisted of children low in reading achievement, those low in math achievement, and those identified as learning disabled. Frequency judgment accuracy increased from kindergarten to Grades 2 and 3. No other comparisons yielded significant differences. Experiment 2 confirmed both the above age difference and the absence of any frequency judgment deficiency on the part of the low-achieving groups.     

Children's understanding of the link between situation and emotion

Children of 6 and 10 years were assessed in three experiments for their insight into emotional reactions that are not directly linked to the current situation. Experiment 1 showed that both age groups know that emotion gradually wanes, after the precipitating situation. Experiment 2 showed that both age groups, but especially 6-year-olds, have difficulty in admitting that a single situation can provoke an emotional conflict between a positive and a negative emotion. Experiment 3 showed, on the other hand, that both age groups understand how an earlier situation can provoke an emotion that persists so as to eventually be concurrent with a later, conflicting emotion. Overall, the results show that both age groups understand that a person's current emotional state cannot be directly inferred from his or her immediate situation. Yet they have considerable difficulty in admitting that a single situation can sometimes provoke both a positive and a negative emotion.     

Production of narrative discourse in aphasia

The study described the abilities of a group of 15 moderately impaired aphasics and 15 normals to produce narrative discourse. The experimental tasks included telling stories, summarizing stories, and giving morals to stories. The data were analyzed in terms of sentential grammar, discourse grammar, and subjective ratings of content and clarity of language. The results showed that aphasics produced well-structured discourse. The language of the aphasics' discourse was reduced in both complexity and amount, as compared to that produced by normals. The reduction of language reflected selective reduction of hierarchically organized information. The findings of the study confirm the results of previous research on mildly impaired aphasics, which also showed preservation of discourse structure with selective reduction of information.     

Central auditory processing. VI. Detecting ear dominance by evoked potentials

An electrophysiological method is described for measuring the direction and strength of a subject's ear dominance for pitch using the P3 component of event-related potentials. Results of these experiments reveal that the P3 can be used effectively for these measures in man.     

Auditory lateralization: An effect of rhythm

Recall of monaurally presented semantically anomalous sentences, which had either neutral or rhythmic timing, was tested at the right ear, at the left ear, and on transfer from one ear to the other. The component words, being computer stored digitized waveforms, had identical acoustic structure in the two conditions. In the rhythmic condition there was not only an overall advantage in the second half of the experiment but also an asymmetric transfer effect such that this advantage did not appear when the left ear was tested after the right. It is proposed that functional lateralization be viewed as an adaptive, dynamic, organizational factor.     

Place versus response as the basis of spatial errors made by young infants

Nine-month-old infants search successfully for an object which they have seen hidden in one position, but they frequently continue to search for it there after observing it being hidden in a new position. This error can be explained in terms either of egocentric response perseveration or of perseveration to a particular place in space. In order to distinguish between these hypotheses, 80 infants were presented with a problem consisting of several different conditions which separated response, position on a table, and absolute spatial position as factors leading to errors in search for hidden objects. The results strongly support the egocentric response hypothesis. The reason for this response perseveration strategy is discussed in terms of the lack of active experience of spatial displacements among 9-month-old infants.