Paralinguistic processing in children with callosal agenesis: emergence of neurolinguistic deficits

Recent research revealed impaired processing of both nonliteral meaning and affective prosody in adults with agenesis of the corpus callosum (ACC) and normal intelligence. Since normal children have incomplete myelination of the corpus callosum, it was hypothesized that paralanguage deficits in children with ACC would be less apparent relative to their peers. The Familiar and Novel Language Comprehension Test (FANL-C) and Prosody Test were given to 18 children with ACC and normal intelligence and 17 controls matched for age (7-13 years), education, and IQ (83-122). When controlling for age, children with ACC were significantly poorer in comprehension of the precise meaning of both literal and nonliteral items on the FANL-C. Adults with ACC had previously been shown to have difficulty only on nonliteral items. The effect size for nonliteral comprehension in children with ACC was smaller than that seen in adults. There was only a trend for the child ACC group to perform worse on the recognition of affective prosody. Thus, while deficits in paralinguistic processing were apparent, children with ACC were not as clearly different from age peers as adults, and were equally deficient at comprehending literal and nonliteral expressions. The differences in results between adults and children with ACC are thought to reflect incomplete callosal development in normal children, and the importance of the corpus callosum in the early stages of the development of the ability to process literal language.     

Children learn when their teacher's gestures and speech differ

Teachers gesture when they teach, and those gestures do not always convey the same information as their speech. Gesture thus offers learners a second message. To determine whether learners take advantage of this offer, we gave 160 children in the third and fourth grades instruction in mathematical equivalence. Children were taught either one or two problem-solving strategies in speech accompanied by no gesture, gesture conveying the same strategy, or gesture conveying a different strategy. The children were likely to profit from instruction with gesture, but only when it conveyed a different strategy than speech did. Moreover, two strategies were effective in promoting learning only when the second strategy was taught in gesture, not speech. Gesture thus has an active hand in learning.     

The wane of childhood amnesia for autobiographical and public event memories

We modified Bruce, Dolan, and Phillips-Grant's (2000) threshold procedure for determining the wane of childhood amnesia. In two experiments, undergraduates labelled childhood events (e.g., your first permanent tooth came in) as know or recollect memories and estimated their age at the event's occurrence. In both studies the estimated transition from mostly know memories to mostly recollect memories was roughly 4.7 years. This transition estimate was replicated in a sample of adults (ages 24-65 years) with both Bruce et al.'s event-generation task and the Experiment 1a questionnaire. By contrast, in two experiments a transition estimate of roughly 6 years was found for undergraduates' memories of public events (e.g., the Challenger explosion). The wane of childhood amnesia appears to occur around 4.7 years.     

Construct validity of the Balloon Analog Risk Task (BART): associations with psychopathy and impulsivity

To continue research assessing the validity of the Balloon Analog Risk Task (BART) as a measure of risk taking, the BART was administered to a nonforensic sample of individuals with varying levels of psychopathic characteristics. Construct validity of the BART was evaluated by measuring risk-taking behavior in relation to self-reported psychopathy, anxiety, psychophysiological data, and demographic variables. Supporting the construct validity of the BART, while controlling for variance accounted for by interrelated variables in the context of hierarchical regression analyses, higher self-reported psychopathy was significantly predictive of increased risk taking on the BART. Findings also revealed interesting gender differences in self-reported psychopathy and a trend for men to engage in riskier behavior. Limitations and research directions are presented.     

Toddlers recognize verbs in novel situations and sentences

Toddlers' (MA=22 and 27 months) ability to extend newly taught verbs to new situational and sentential contexts was investigated. Children were interactively taught two novel verbs, presented in only the transitive frame (e.g. You're lorping the ball), in a playroom setting. They then viewed the verb actions presented on side-by-side monitors and were asked to distinguish the verbs in three test frames (transitive, intransitive, neutral (e.g. lorping)). Both groups demonstrated learning of the verbs in the new situation and generalized the verbs to the intransitive sentence frame, but neither generalized reliably to the neutral frame. We conclude that even 22-month-olds demonstrate considerable context independence in their verb representations.     

Effect of Children's Perceived Rejection on Physical Aggression

This study investigated whether the perception of self as socially rejected might contribute to increased physical aggression among elementary-school children. It was hypothesized that physically aggressive children would become more physically aggressive over time if they perceived that they were rejected and tended to blame peers for social failure experiences. Third-grade boys and girls (n = 941) were assessed in the Fall and Spring of the school year. Peer-report data on physical aggression and social preference were collected, along with self-report data on perceived rejection and attributions for social failure experiences. Results for boys were consistent with hypotheses, whereas the results for girls revealed a different pattern of relations. These results constitute prospective evidence that children's self-perceptions of social rejection can uniquely influence externalizing behavior. Results are discussed in terms of mechanisms that might mediate the relation between perceived rejection and physical aggression.     

Are dietary restraint scales valid measures of acute dietary restriction? Unobtrusive observational data suggest not

The finding that dietary restraint scales predict onset of bulimic pathology has been interpreted as suggesting that dieting causes this eating disturbance, despite the dearth of evidence that these scales are valid measures of dietary restriction. The authors conducted 4 studies that tested whether dietary restraint scales were inversely correlated with unobtrusively measured caloric intake. These studies, which varied in foods consumed, settings, and populations, indicated that common dietary restraint scales were largely uncorrelated with acute caloric intake. Results suggest that these scales are not valid measures of short-term dietary restriction and imply that it may be prudent to reinterpret findings from studies thai use these scales, including those that suggest dietary restraint is a risk factor for bulimic pathology.     

And when shall a little child lead them? evidence for an altercasting theory of source credibility

In two crucial test experiments pitting altercasting against traditional source credibility theories (Hovland, Janis, & Kelley, 1953; Kelman, 1958), students received a message emphasizing either technical or protective themes attributed to a child or an expert. Traditional theories predict an expert should be more effective than a child. According to altercasting theory, credibility is a function of the privileges and responsibilities associated with positions in a role-set. A child places a message recipient into the role of protector and is most effective when arguing for protective as opposed to technical messages. An expert is most effective when arguing within a domain of expertise (technical issues) as opposed to common opinion. The results overwhelmingly support an altercasting interpretation of source credibility.     

Beyond the individual: the impact of ethnic context and classroom behavioral norms on victims' adjustment

With a sample of 1,630 sixth-grade students from 77 classrooms, the authors used hierarchical linear modeling to examine how ethnicity within context and classroom social disorder influenced the association between peer victimization and social-psychological adjustment (loneliness and social anxiety). Victimized students in classrooms where many classmates shared their ethnicity reported feeling the most loneliness and social anxiety. Additionally, classroom-level social disorder served as a moderator such that the association between victimization and anxiety was stronger in classrooms with low social disorder. Both findings were interpreted as evidence that problem behavior deviating from what is perceived as normative in a particular context heightens maladjustment. The authors discuss implications for studying ethnicity and classroom behavioral norms as context variables in peer relations.     

Knowledge about the probability of change affects change detection performance

The visual system continually selects some information for processing while bypassing the processing of other information, and as a consequence, participants often fail to notice large changes to visual stimuli. In the present studies, the authors investigated whether knowledge about the probability of particular changes occurring over time increased the likelihood that changes that were likely to occur in the real world (probable changes) would be detected. The results of two experiments showed that participants were more likely to detect probable changes. This occurred whether or not they were processing the scene in a meaningful manner or actively searching the scene for changes. Furthermore, participants were unable to accurately predict change detection performance for probable and improbable changes.