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981.
Convergent data suggest dissociated roles for the lateral (LA) and basolateral (BLA) amygdaloid nuclei in fear conditioning, depending on whether a discrete conditioned stimulus (CS)-unconditional stimulus (US) or context-US association is considered. Here, we show that pretraining inactivation of the BLA selectively impaired conditioning to context. In contrast, inactivation of the LA disrupted conditioning to the discrete tone CS, but also either impaired or enhanced contextual conditioning, depending on whether the context was in the foreground or in the background. Hence, these findings refine the current model of the amygdala function in emotional learning by showing that the BLA and the LA not only differentially contribute to elemental and context-US association, but also promote, through their interaction, the most relevant of these two associations.  相似文献   
982.
To provide a better estimate of the prevalence of ADHD in adulthood, the authors complete a telephone survey of 966 randomly selected adults. They compute two diagnoses from the survey data. Participants meeting Diagnostic and Statistical Manual of Mental Disorders (4th ed.) criteria for both childhood and adulthood are defined as narrow ADHD. Broad ADHD adds to that definition those meeting subthreshold criteria. Cronbach's alpha is .90 for the 18 DSM-IV symptoms in childhood and .88 when rated for current symptoms in adulthood. No one item unduly influences the reliability of the total score. The authors find similar results in separate analyses of hyperactive-impulsive and inattentive symptoms. They estimate prevalences of 2.9% for Narrow ADHD and 16.4% for Broad ADHD. Having ADHD is associated with lower levels of education and employment status. These findings suggest that adult ADHD is a common disorder associated with impaired functioning.  相似文献   
983.
Short measures of child inattention-overactivity (IO), aggression-defiance (AG), and anxiety-depression or emotionality (EM) derived through a double validation procedure are administered to mothers of 243 clinic-referred suburban New York boys between 6 and 10 years of age. Mother-rated IO is uniquely related to poor performance on cognitive and achievement tests; observed inattentive, hyperactive, and impulsive behaviors in a restricted academic setting; less father education and lower family income; and most mother-reported impairments and treatment use. Mothers of high-IO boys describe themselves and their sons as having similar childhood symptoms. AG is uniquely related to child-reported disruptive behavior and sensation seeking, many measures of family conflict and negative parenting styles, and mother-reported symptom pervasiveness and number of treatments. EM is uniquely related only to poorer cognitive and achievement test performance, living with one parent, parents who considered themselves too busy, and fewer friends. Each dimension also is associated with parallel teacher-rated factors.  相似文献   
984.
Many studies of ADHD have shown that the problems associated with the disorder continue into adolescence and beyond for 10% to 60% of patients. The present study assesses several aspects of college adjustment, social skills, and self-esteem in a nonreferred sample of college students meeting criteria for a Diagnostic and Statistical Manual of Mental Disorders (4th ed.) diagnosis of ADHD. Twenty-one undergraduate students with symptoms of ADHD are compared to 20 students without significant ADHD symptoms, who match the ADHD students on age, gender, and grade point average. Students with ADHD symptoms show decreased functioning in several areas of college adjustment as well as lower levels of self-reported social skills and self-esteem. The results also suggest that the relation between ADHD and college adjustment is partially mediated by self-reported levels of self-esteem.  相似文献   
985.
Angiotensin II (ANGII) has an evolutionary preserved role in determining adaptative responses to water-shortages. In addition, it has been shown to modulate diverse phases of memory. Still, it is not clear whether ANGII improves or spoils memory. We demonstrated that endogenous angiotensins enhance consolidation of a long-term associative memory in the crab Chasmagnathus and that water shortage improves memory consolidation through brain ANGII actions. Here, we show that weakly trained crabs, when water-deprived, exhibit enhanced retrieval. Subsequently, memory retention is indistinguishable from that of strongly trained crabs. ANGII, but not angiotensin IV, is a necessary and sufficient condition for such enhancing effect. We conclude that ANGII released due to water shortage leads to enhanced memory retrieval. Thus, it seems that ANGII has an evolutionary preserved role as a multifunction coordinator that enables an adaptative response to water-shortage. The facilitation of memory consolidation and retrieval would be among those coordinated functions.  相似文献   
986.
The effects of rehearsing actions by source (slideshow vs. story) and of test modality (picture vs. verbal) on source monitoring were examined. Seven- to 8-year-old children (N = 30) saw a slideshow event and heard a story about a similar event. One to 2 days later, they recalled the events by source (source recall), recalled the events without reference to source (no-source-cue recall), or engaged in no recall. Seven to 8 days later, all children received verbal and picture source-monitoring tests. Children in the source recall group were less likely than children in the other groups to claim they saw actions merely heard in the story. No-source-cue recall impaired source identification of story actions. The picture test enhanced recognition, but not source monitoring, of slide actions. Increasing the distinctiveness of the target events (Experiment 2) allowed the picture test to facilitate slideshow action discrimination by children in the no-recall group.  相似文献   
987.
Recent clinical trials of secretin in children with autism showed robust placebo effects and no benefit of secretin over placebo. This article explores the reasons for the observed placebo effects, focusing on the heightening of positive expectancy by media attention and by the sensory experiences associated with intravenous injections. Comparisons are drawn with research involving other novel treatments and other clinical populations of children with developmental disabilities and neurobehavioral disorders. Research regarding mechanisms of placebo effects is reviewed, including patient and clinician attributes, expectancy effects, participation effects, changes in caregiver behavior, and conditioning. New evidence regarding the biological basis of placebo effects is briefly presented. Since placebo effects are ubiquitous and may operate by a variety of mechanisms, research design is critical in designing clinical trials and in evaluating other outcomes research. Measurement issues important for research in developmental disabilities are emphasized. Ethical concerns have been raised regarding the use of placebo in clinical research, but current analysis suggests that placebo controls are necessary and defensible on ethical grounds, if certain conditions are met. The study of placebo effects ("placebology") holds great promise as a new area of research in therapeutics. The author's research in the potential augmentation of stimulant effects in children with attention deficit/hyperactivity disorder (ADHD) by adding placebo in open label is briefly presented. The placebo has always been integral to the practice of medicine, but advances in scientific medicine and medical ethics have diminished the role and use of placebo in practice. An innovative approach to the ethical use of placebo is proposed.  相似文献   
988.
Mixed amphetamine salts extended release (MAS XR; Adderall XR) and atomoxetine (Strattera) were compared in children 6 to 12 years old with attention deficit/hyperactivity disorder (ADHD) combined or hyperactive/impulsive type in a randomized, double-blind, multicenter, parallel-group, forced-dose-escalation laboratory school study. Primary efficacy measure was the SKAMP (Swanson, Kotkin, Agler, M-Flynn, and Pelham) behavioral rating scale. Changes in mean SKAMP deportment scores from baseline were significantly greater for MAS XR (n = 102) than for atomoxetine (n = 101) overall (-0.56 and -0.13, respectively; p < .0001) and at each week (p < .001). Adverse events were similar for both treatment groups. The extended time course of action and greater therapeutic efficacy of MAS XR suggests that it is more effective than atomoxetine in children with ADHD.  相似文献   
989.
990.
Schizophrenia and obsessive-compulsive disorder (OCD) have historical, clinical, and epidemiological links. The clinical use of atypical neuroleptics (ie, dual serotonin-dopamine antagonists) to treat both conditions sheds a new light on them. We report the first two cases of obsessive-compulsive symptoms (OCS) induced by quetiapine in schizophrenia patients. A case of successful augmentation by quetiapine in refractory OCD is also presented. A review of the literature on OCS induced by atypical neuroleptics follows. This paradoxically induced OCD symptomology in schizophrenia patients administered atypical neuroleptics is discussed from new pathophysiological and clinical perspectives. The discussion emphasizes the prognostic implications of OCS in schizophrenia and available therapies for this comorbidity.  相似文献   
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