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841.
842.
We measured subjective-tone identification thresholds evoked by acoustically filtered complex tones and compared them to Mandarin-Chinese tone-phoneme identification thresholds previously measured under the same filtering conditions. Tone phonemes were identified at intensities below subjective-tone identification thresholds, suggesting subjective tone is not necessary for tone-phoneme identification. Lower subjective-tone thresholds evoked by resolved harmonics rather than unresolved harmonics were consistent with pattern recognition theories of pitch perception.The authors thank Donald Gans and Richard Klich for all their help.  相似文献   
843.
Analyzed case records to determine the costs and service usage patterns for a group of 25 youth randomly selected from the case load of a regional mental health agency. Study participants had extensive histories of publicly supported psychiatric hospitalizations. An average of 36.2 contacts per youth (905 total contacts) with human services providers were documented. Approximately 2 out of every 5 contacts resulted in out-of-home placements. The estimated cost of providing services to the 25 youth exceeded 3 million dollars. The types and costs of treatment services provided to study participants are discussed.  相似文献   
844.
Examined the effects of precautionary behavior on subsequent criminal victimization, fear of crime, and psychological distress. A sample of 538 adults was interviewed three times at 6-month intervals. Four different aspects of precaution were assessed: vigilance (alertness), locks (access control), neighbors (informal cooperation), and professionals (formal programs). In logistic regressions that controlled for 14 risk factors, precaution had no preventive effects on the occurrence of subsequent crimes. LISREL models revealed that use of neighbors was the only precaution not to increase fear of crime, although both locks and neighbors showed a capacity to buffer the effects of fear on generalized distress. It was concluded that the most promising strategy was protective neighboring. Altogether, however, the promotion of citizen-initiated prevention appears highly inadequate as a policy response to problems of crime and fear.  相似文献   
845.
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   
846.
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   
847.
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   
848.
849.
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   
850.
The local anesthetic lidocaine (XILOCAINA), 2%, was injected into the tissue surrounding the anterior region of the third cerebral ventricle (AV3V) of the rat, through a permanently implanted cannula, to produce a temporary and reversible disruption of the nervous connections of this area with other cellular nuclei while leaving the vascular connections intact. Following 24 h water deprivation, lidocaine was injected, and after 20 min water intake decreased; subsequently, the lidocaine-injected rats behaved similarly to control rats injected with artificial cerebrospinal fluid. Osmotic drinking was not affected. Prolonged adipsia or hyperdipsia did not occur. In nondeprived rats, lidocaine prevented angiotensin II-induced drinking. Following 24 h sodium depletion by peritoneal dialysis, lidocaine decreased the specific sodium appetite by 50% in animals with different levels of body sodium depletion. The data indicate that the integrity of the neural tissue of the AV3V is essential for a correct body water-salt regulation. Temporary "ablation" with lidocaine, which blocked neural activity but maintained the blood supply, produced responses different from most of those reported after electrolytic lesions. Therefore, lidocaine may be used as a tool to assess the response of this neural tissue to body fluid regulation.  相似文献   
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