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991.
In previous experiments on event-related potentials (ERPs) during linguistic judgments, the subjects' decisions have been categorical (e.g., true vs false). In this experiment, more realistic variations in truth value and subject certainty were used. Thirty-eight naive undergraduates read a story about a fictional murder. ERPs were recorded as the subjects rated the strength of their beliefs about statements relating to suspects in the crime. Because no subject was sure which of the suspects was guilty of committing the crime, binary (true–false) category judgments were inappropriate. Three components of the ERP waveforms were affected by the experimental manipulations. An early positive component was largest to sentences concerning the suspect considered most likely to have committed the crime. A subsequent broad posterior positivity (LPC) also showed significant sentence-type differences, but it was larger to sentences considered probable—whether they were true or false—than to more ambiguous sentences. A third ERP component (N400) was negative at midline electrode sites and peaked at approximately 420 ms. Subjects' truth-value judgments had no effect on the N400. N400 was, however, affected by the subject's task. It was more negative when subjects made graded judgments about truth value than when they made binary true–false judgments. Overall, naturalistic judgments of sentence validity produced a variety of brain responses that reflected different aspects of linguistic decision making. 相似文献
992.
David A. Abwender Kimberly S. Trinidad Kathy R. Jones Peter G. Como Enid Hymes Roger Kurlan 《Brain and language》1998,62(3):455-464
Developmental stuttering (DS) may be related to the extrapyramidal motor system and shares many clinical similarities with Tourette's syndrome (TS), which is widely believed to be associated with extrapyramidal dysfunction. Twenty-two stutterers were examined for neuropsychiatric features commonly seen in TS, including tics, obsessive-compulsive behaviors (OCB), and attention deficit disorders. Eleven stutterers displayed motor tics, and symptoms of OCB were observed at rates similar to those seen in persons with TS. Few stutterers demonstrated significant attentional deficits. Findings are consistent with models suggesting extrapyramidal involvement in DS and raise the possibility that DS and TS are pathogenetically related. 相似文献
993.
Gregory M. Herek J. Roy Gillis Eric K. Glunt Jeffrey Lewis David Welton John P. Capitanio 《American journal of community psychology》1998,26(5):705-743
The importance of using culturally sensitive educational materials in HIV-related interventions with racial and ethnic minority groups is widely recognized. However, little empirical research has been conducted to assess the relative effectiveness of different techniques for creating culturally sensitive AIDS educational videos. Two field experiments with three samples of African American adults (N = 174, 173, and 143) were conducted to assess how source characteristics (race of communicator), message characteristics (multicultural message vs. culturally specific message), and audience characteristics (racial distrust and AIDS-related distrust) influence proximate (perceptions of the message's credibility and attractiveness) and distal (AIDS-related attitudes, beliefs, and behavioral intentions) output variables for AIDS educational videos. In Study 1, an AIDS video with a culturally specific message was rated as more credible, more attractive, and of higher quality than was a video with a multicultural message. The multicultural message was rated less favorably when delivered by a White announcer than when the announcer was Black. In Study 2, the same pattern was replicated with a second community sample and a campus-based sample. Study 2 also indicated that a multicultural message might be more effective if delivered in a culturally specific context, namely, after audience members watch a culturally specific video. Minimal changes were observed in distal outcome variables. It is argued that influencing proximate output variables is necessary, though not sufficient, for effecting long-term change in AIDS-related attitudes, beliefs, and behaviors. 相似文献
994.
Kenneth A. Chase Dominique Treboux K. Daniel O'Leary Zvi Strassberg 《Journal of abnormal child psychology》1998,26(6):467-473
Ninety-five high-risk adolescents were studied to determine whether their dating aggression and its justification as a response to interpersonal problems were specific to the current partner, general to dating relationships, or part of a global age-mate (same-sex peers and opposite-sex dating partners) aggression problem. Approximately one-third of males and two-thirds of females reported physical aggression against their current dating partner. Males' aggression (and its justification) toward their current dating partner was part of a generalized pattern of dating aggression, whereas for females, physical aggression against a current dating partner (and its justification) was partner-specific and unrelated to aggression in other relationships. Findings are discussed with regard to intervention and future research on adolescent dating aggression. 相似文献
995.
Michael G. Sawyer David L. Streiner Peter Baghurst 《Journal of abnormal child psychology》1998,26(6):407-414
This study examined the effect of parental distress on mothers' and fathers' reports of children's emotional and behavioral problems. The subjects were the parents of 696 children aged 10 to 11 or 14 to 15 years living in two-parent families in the community. The study utilized an extended version of the model previously employed by Fergusson, Lynskey, and Horwood (1993) to examine the impact of maternal depression on mothers' reports of children's behavior. In the present study, the extended model was used to assess the impact of distress on reports of childhood externalizing and internalizing problems obtained from both mothers and fathers. The results suggested that distress had little influence on mothers' or fathers' reports of childhood behavior problems. It is concluded that in community studies the size of any bias in mothers' and fathers' reports of childhood behavior problems due to parental distress is likely to be very small and of little clinical significance. 相似文献
996.
David Schwartz Kenneth A. Dodge John D. Coie Julie A. Hubbard Antonius H. N. Cillessen Elizabeth A. Lemerise Helen Bateman 《Journal of abnormal child psychology》1998,26(6):431-440
A contrived play group procedure was utilized to examine the behavioral and social-cognitive correlates of reactive aggression, proactive aggression, and victimization via peers. Eleven play groups, each of which consisted of six familiar African-American 8-year-old boys, met for 45-min sessions on five consecutive days. Social-cognitive interviews were conducted following the second and fourth sessions. Play group interactions were videotaped and examined by trained observers. High rates of proactive aggression were associated with positive outcome expectancies for aggression/assertion, frequent displays of assertive social behavior, and low rates of submissive behavior. Reactive aggression was associated with hostile attributional tendencies and frequent victimization by peers. Victimization was associated with submissive behavior, hostile attributional bias, reactive aggression, and negative outcome expectations for aggression/assertion. These results demonstrate that there is a theoretically coherent and empirically distinct set of correlates associated with each of the examined aggression subtypes, and with victimization by peers. 相似文献
997.
Sydney S. Zentall Arlene M. Hall David L. Lee 《Journal of abnormal child psychology》1998,26(5):335-343
Mirrors have been used to focus attention to aspects of the self (e.g., to known strategies, standards). We hypothesized that this could be important for students with hyperactivity/inattention, who typically direct attention outward to external novelty. In this study, we administered a partially solvable word puzzle to 43 middle school students, with and without hyperactivity/inattention, in the presence and absence of a mirror, counterbalanced for condition and form order. Differences between students with hyperactivity/inattention and comparisons in accuracy were found only in the no mirror condition. Furthermore, the beneficial effect of the mirror for children with hyperactivity/inattention was most pronounced for those who looked at the mirror. Findings were interpreted in terms of their potential to remedy the production deficits of these children. 相似文献
998.
Donna K. Wood Alan R. Frank David P. Wacker 《Journal of applied behavior analysis》1998,31(3):323-338
Multiple baseline designs were used to examine the effects of an instructional package on accuracy of performance in solving multiplication facts by 3 students with learning disabilities. The instructional package included the following components: (a) a modified instructional sequence in which multiplication facts were grouped into the zeros, ones, doubles, fives, and nines categories, and those remaining; (b) identification of the category in which each fact belonged; (c) mnemonic strategies associated with solving facts in each category; and (d) steps to be completed for solving facts in each category. Results indicated that the instructional package produced substantial and immediate effects. After receiving instruction, a participant's accuracy was often 100%, and this was maintained throughout the evaluation even as other strategies were introduced. Comparable results occurred across students, demonstrating replication of the effects of the instructional package. 相似文献
999.
David M. Fergusson Michael T. Lynskey L. John Horwood 《Journal of abnormal child psychology》1996,24(4):499-512
The associations between early onset (prior to 15 years of age) cannabis use and rates of mental health or adjustment problems during the period from 15 to 16 years of age were studied in a New Zealand birth cohort. Early onset cannabis users were at increased risks of later substance use behaviors, conduct/oppositional disorders, juvenile offending, severe truancy, school dropout, anxiety, depression, and suicidal ideation. Early cannabis users had odds of these outcomes ranging from 2.7 to 30.8 times higher than the odds for those who did not use cannabis prior to age 15. Most of the elevated risks of early onset users were explained by the fact that they were a high-risk group of adolescents characterized by family disadvantages, early adjustment problems, and high affiliations with substance-using or delinquent peers. Nonetheless, even after adjustment for a wide range of confounding factors, early onset users had increased risks of later cannabis use. It is concluded that while most of the elevated risks of early onset users were explained by social, family, and individual characteristics of this group, early onset users were at increased risks of later cannabis use.This research was funded by grants from the Health Research Council of New Zealand, the National Child Health Research Foundation and the Canterbury Medical Research Foundation. 相似文献
1000.
To determine the relative impact of a number of family variables on children's performance of gender-typed household tasks, this study took account of the gender of the child, the gender of a sibling within the same age range (8–14 years), whether a first or second child and three parental variables: the degree of encouragement given to perform masculineand femininetasks, parental involvement in the same tasks, and parents' general egalitarianism. The sample consisted of 191 white, mainly Anglo Australian two-parent families, with the two oldest children in a boy—boy, girl—girl, boy—girl, or girl—boy sequence. To check on the robustness of effects, measures were taken on two occasions, on average 16 months apart. Among the family context variables, the gender of the child was the strongest contributing variable, with girls doing more feminine tasks than boys and boys doing more masculine tasks than girls. There was limited support for the proposition that first children do more housework than second children of the same gender, while the results for gender of sibling were small and inconsistent. Among the parental variables, encouragement had strong positive effects for feminine tasks (i.e., more encouragement by parents corresponded to more involvement by children). In contrast, parental involvement in the same tasks (modeling) and parental egalitarianism predicted only the performance of masculine tasks, and the direction of the effects was mostly negative (e.g., the more a father was involved in masculine tasks, the less a child did of those tasks). The results point to involvement in gender-typed activities being influenced by multiple factors, with parental encouragement and gender of child being most prominent among these. They also point to the value of sampling on more than one occasion and of considering separately the performance of feminine and masculine tasks.
This research was financially supported by the Australian Research Council. We are happy to acknowledge that support, together with the essential assistance of the Department of Education and the many parents and children who participated in the study. 相似文献