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921.
Investigated predictors of five measures of early school adjustment for an ethnically diverse cohort of 683 inner-city kindergartners and first graders. Data from 2 consecutive years were collected from teachers, school records, and children. A multiple-regression preduction model significantly explained children's competence behavior, problem behavior, reading achievement, mathematics achievement, and school absences. Prior adjustment and sociodemographic factors explained a majority of the variance in adjustment. Perceived quality of parent involvement was signifcantly related (in the expected direction) to all five outcomes. Exposure to life events was significantly associated in the expected direction with competence behavior, problem behavior, and school absences but not with reading and mathematics achievement. Together, parent involvement and life-event variables explained as much as 12% of the variance in adjustment independent of sociodemographic and prior adjustment factors. The role of family and school factors in the adjustment of children at risk is discussed [corrected].  相似文献   
922.
Prior research has shown that parenting stress levels can be quite high among families of children with attention deficit hyperactivity disorder (ADHD). This study investigated the degree to which such stress was related not only to the child's ADHD, but also to various other child, parent, and family-environment circumstances. Multimethod assessments were conducted on 104 clinic-referred children with ADHD. Data collected from these subjects were entered into hierarchical multiple-regression analyses, utilizing the Parenting Stress Index as the criterion. The results showed that child and parent characteristics accounted for a substantial portion of the variance in overall parenting stress. The child's oppositional-defiant behavior and maternal psychopathology were especially potent predictors. The severity of the child's ADHD, the child's health status, and maternal health status also emerged as significant predictors. These findings are discussed in terms of their impact upon the clinical management of children with ADHD.The authors are grateful to Mary Maher and Paula Nevins for their assistance in collecting and coding the data. The authors would also like to thank Dr. Kenneth Fletcher for his helpful comments regarding the statistical analyses.  相似文献   
923.
A short-term longitudinal study was conducted to determine whether self-regulation at 4 years could be predicted from child and maternal measures obtained when the children were age 24 months. The subjects were 69 children and their mothers drawn from the general community. Criterion behaviors assessed at 4 years were those suggestive of attention-deficit hyperactivity disorder. Of the 24-month child measures, maternal ratings of the child's impulsivity and attention span, plus an objective measure of delay ability, were the most effective predictors. Maternal negativity, as assessed in mother-child interaction, predicted the criterion behaviors, even after the child's behavior as an elicitor of maternal behavior was controlled. Maternal child-rearing attitudes on the dimensions of warmth and aggravation were also effective predictors, even after controlling for the child's emotionality as a possible determinant of maternal attitudes. It is argued that the results with the maternal attitude measures provide support for the hypothesis that maternal behavior is a contributor to the development of self-regulation.This research was supported by a State of Ohio Academic Challenge Grant to the Bowling Green State University Clinical Psychology Program, and by a Basic Grant awarded to the first author by the Bowling Green State University Faculty Research Committee. The authors are grateful to Eric Dubow, Douglas Ullman, and two anonymous reviewers for their helpful comments and criticisms on previous versions of this article.  相似文献   
924.
925.
This study examined narrative discourse in 20 children and adolescents at least 1 year after sustaining a head injury. Narratives were analyzed along the dimensions of language structure, information structure, and flow of information. Severity of impaired consciousness was associated with a significant reduction in the amount of language and information. The most important finding which emerged was the disruption in information structure. This pattern confirms the impression of disorganized discourse in severely injured children. Explanations for the disruption in information structure are explored in terms of the role of vocabulary, memory, and localization of lesion according to magnetic resonance imaging. In view of recent evidence that frontal lobe damage is associated with discourse formulation deficits in adults and is the most common site of focal lesion in closed head injury, we examined discourse patterns in individual patients with frontal lobe lesions. Preliminary data from our single-case studies suggest discourse patterns similar to those reported for adults with frontal lobe injuries.  相似文献   
926.
Twenty-four boys with attention deficit-hyperactivity disorder (ADHD) participating in an intensive summer treatment program each received b.i.d. placebo and two doses of methylphenidate (MPH, 0.3 mg/kg and 0.6 mg/kg) crossed with two classroom settings: a behavior modification classroom including a token economy system, time out and daily home report card, and a regular classroom setting not using these procedures. Dependent variables included classroom observations of on-task and disruptive behavior, academic work completion and accuracy, and daily self-ratings of performance. Both MPH and behavior modification alone significantly improved children's classroom behavior, but only MPH improved children's academic productivity and accuracy. Singly, behavior therapy and 0.3 mg/kg PMH produced roughly equivalent improvements in classroom behavior. Further, the combination of behavior therapy and 0.3 mg/kg MPH resulted in maximal behavioral improvements, which were nearly identical to those obtained with 0.6 mg/kg MPH alone.The authors gratefully acknowledge the assistance of Patricia Donovan, Michelle Berry, Mary Ingram, Patricia Wells, Beth Gnagy, Karen Greenslade, Mary Hamilton, and the entire staff of the Western Psychiatric Institute and Clinic ADHD Summer Treatment Program.  相似文献   
927.
Rats submitted to a chronic variable stress regime exhibited more inactivity during inescapable shock as compared with unstressed rats. Besides, chronic treatments with desipramine, imipramine, clomipramine, or phenelzine reduce the amount of inactivity exhibited during this aversive experience. Furthermore, the combination of both chronic treatments--stress and antidepressants--resulted in a potentiation of the antidepressant effect alone. This higher antidepressant efficacy may result from the interaction of the neural mechanisms triggered by chronic stress exposure and antidepressant drugs.  相似文献   
928.
Norway rat fetuses (Rattus norvegicus) exhibit a stereotypic behavioral response when the umbilical cord is experimentally compressed with a vascular clamp. In this study, the development of the fetal behavioral response to cord compression was compared in altricial and precocial rodents, which differ markedly in neural and motor maturity at the time of birth. Both altricial and precocial species showed some form of behavioral response to umbilical cord compression. Fetuses of two altricial species, Norway rats and Mongolian gerbils (Meriones unguiculatus), expressed hyperactivity in response to cord compression throughout the last third of gestation. In contrast, precocial cotton rats (Sigmodon hispidus) and spiny mice (Acomys cahirinus) did not respond to cord compression until relatively late in gestation. Thus, altricial and precocial species do not express the cord compression response during comparable periods of neural development: precocial species are much more mature at the earliest expression of this behavior than altricial species. These findings are consistent with the interpretation that the cord compression response is a behavioral adaptation that can promote survival of the fetus in utero.  相似文献   
929.
Learning a bimanual coordination task (synchronization to a visually specified phasing relation) was studied as a dynamical process over 5 days of practicing a required phasing pattern. Systematic probes of the attractor layout of the 5 Ss' coordination dynamics (expressed through a collective variable, relative phase) were conducted before, during, and after practice. Depending on the relationship between the initial coordination dynamics (so-called intrinsic dynamics) and the pattern to be learned (termed behavioral information, which acts as an attractor of the coordination dynamics toward the required phasing), qualitative changes in the phase diagram occurred with learning, accompanied by quantitative evidence for loss of stability (phase transitions). Such effects persisted beyond 1 week. The nature of change due to learning (e.g., abrupt vs. gradual) is shown to arise from the cooperative or competitive interplay between behavioral information and the intrinsic dynamics.  相似文献   
930.
The hypothesis that representation of projective shape is preattentive whereas representation of objective shape in three-dimensional space requires allocation of attention was tested in 2 visual search and 2 precuing experiments. In the visual search experiments, the slope for projective shape search was expected to approach 0 and that for objective shape search was expected to be a positive monotonic function of set size. In the precuing experiments, the effects of precuing were expected to be largely limited to the task requiring representation of objective shape. The overall pattern of results conformed to expectations. The findings are interpreted in the context of a model of shape-at-a-slant processing set out by Epstein and Lovitts (1985) and Epstein and Babler (1989, 1990).  相似文献   
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