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BACKGROUND: Impaired neuropsychological test performance, especially on tests of executive function and attention, is often seen in children diagnosed with autism spectrum disorders (ASD). Structures involved in fronto-striatal circuitry, such as the caudate nucleus, may support these cognitive abilities. However, few studies have examined caudate volumes specifically in children with ASD, or correlated caudate volumes to cognitive ability. METHODS: Neuropsychological test scores and caudate volumes of children with ASD were compared to those of children with bipolar disorder (BD) and of typically developing (TD) children. The relationship between test performance and caudate volumes was analyzed. RESULTS: The ASD group displayed larger right and left caudate volumes, and modest executive deficits, compared to TD controls. While caudate volume inversely predicted performance on the Wisconsin Card Sorting Test in all participants, it differentially predicted performance on measures of attention across the ASD, BD and TD groups. CONCLUSIONS: Larger caudate volumes were related to impaired problem solving. On a test of attention, larger left caudate volumes predicted increased impulsivity and more omission errors in the ASD group as compared to the TD group, however smaller volume predicted poorer discriminant responding as compared to the BD group.  相似文献   
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BACKGROUND: Effects of risperidone on cognitive function in children with disruptive behavior disorders (DBDs) and subaverage intelligence quotient (IQ) were assessed. METHODS: Data from two 6-week, double-blind, placebo-controlled studies (n = 228) were combined, as were three 1-year, open-label studies (n = 688). Patients with DBDs and subaverage IQ, 5 to14 years, received placebo or risperidone .02 to .06 mg/kg/day. Cognitive measures included the Continuous Performance Task (CPT) and Verbal Learning Test for Children (VLT-C). Efficacy was assessed using the Nisonger Child Behavior Rating Form (NCBRF). Adverse events were collected via spontaneous report; sedation was assessed using visual analog scale. RESULTS: Improvements on the NCBRF Conduct Problem subscale were significantly greater for risperidone- versus placebo-treated patients (-15.8 vs. -6.4, p < .0001) in short-term studies; significant reductions were observed in long-term studies (-16.3, p < .0001). No overall decline and some significant improvement in attention (CPT) and memory (VLT-C) were noted regardless of treatment in short-term studies. VLT-C improved significantly (p < .0001) for both groups, with no difference between treatment groups. Improvements in memory (VLT-C) and attention (CPT) were noted in long-term studies. Somnolence/sedation did not affect cognitive function. CONCLUSIONS: Cognitive function was not altered by risperidone in short-term studies and was maintained or improved with one year of treatment in children with DBDs and subaverage IQ, potentially representing age-appropriate gains.  相似文献   
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Fallone G  Seifer R  Acebo C  Carskadon MA 《Sleep》2002,25(7):739-745
STUDY OBJECTIVES: To quantitatively assess compliance and experimental success with imposed sleep schedules among healthy children involved in an experimental comparison of optimized and restricted sleep. DESIGN: We asked children to follow assigned sleep schedules at home that created optimized (at least 10 hours time-in-bed per night) and restricted (6.5 to 8 hours time-in-bed per night) sleep conditions across 2 weeks during the school year. Self-report or parent-report of bedtime and risetime was obtained daily and continuous actigraphy was recorded. SETTING: Home. PARTICIPANTS: 78 healthy children (41 boys, 37 girls; mean age, 10.2 years; age range, 6.5 to 12.9 years) INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: We used reported time-in-bed to assess noncompliance with assigned schedules. Experimental failure was assessed with actigraphically based estimates of sleep period (time from sleep onset to sleep offset) and total sleep time (minutes of scored sleep during sleep period). Reported time-in-bed averaged 3.45 hours less per night under restricted versus optimized conditions. Sleep period and total sleep time showed similar differences (2.97 and 2.32 hours less, respectively). Four children met a priori criteria for noncompliance (3 for optimized nights and 1 for restricted). Eight children met a priori criteria for experimental failure within conditions (7 for optimized nights and 1 for restricted), but most achieved a substantial difference in sleep behavior across optimized and restricted weeks. CONCLUSIONS: In general, healthy children as young as 6 years of age can maintain substantial changes in their usual schedules across several nights at home and should be considered for inclusion in experimental studies of sleep extension and restriction. This paper offers a methodologic "road-map" for scientists interested in pursuing this goal.  相似文献   
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Forensic science is undertaken in support of law enforcement investigations, criminal justice prosecutions, intelligence, and military objectives. There are different forensic operating models to meet these various objectives and no unified approach to forensic science has been described. There are common challenges in the military domain, which impacts the delivery of forensic science, including: different terminology between organizations, complex operating environments, operating siloes, inward-looking military structures, quality management, and resource constraints. One solution to these challenges is to apply modern organizational theory to military-focused forensic science. Organizational theory is the study of organizations in a structural sense, including objectives, people, structure and management. The modern organizational theory systems approach describes how organizations should be viewed as systems within larger systems. In the work presented in this paper, a systems approach has been applied, for the first time, to military forensic exploitation to address the common issues faced by military organizations. The advantages of applying a systems approach to military forensic exploitation are that it is applicable across forensic science organizations, it is flexible and scalable to meet the changing external environment, and it articulates the redundancies in the system to help address system failures.  相似文献   
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Background

We assessed the impact of juvenile abuse (emotional, physical, or sexual) on response to treatment in adults with major depressive disorder (MDD) suboptimally responsive to antidepressant therapy.

Methods

A post hoc analysis explored the relationship between self-reported history of juvenile abuse and response to risperidone or placebo augmentation during a 6-week double-blind study period in patients with MDD suboptimally responsive to a previous adequate trial of antidepressant monotherapy.

Results

Overall, only one clinical measure showed a small, but statistically significant difference in outcome between patients with abuse versus without abuse (HRSD-17). In patients reporting abuse (n=141), improvement with risperidone versus placebo augmentation was greater on several measures: HRSD-17 total and 2 subscale scores, responder rates, Q-LES-Q, and PaRTS-D. In patients without abuse (n=127), only two measures showed significant improvement: HRSD-17 subscale and PaRTS-D. Responder rates (HRSD-17) were: 40.9% (risperidone) versus 23.1% (placebo; p=0.01; odds ratio=2.7) in those with abuse, and 41.0% versus 34.4% (p=0.39; odds ratio=1.4) in those without. Adverse events rates were: 37.0% (risperidone) and 54.4% (placebo) in patients with abuse, and 56.3% and 55.6% in those without.

Limitations

Analysis not preplanned. Validated questionnaire not used to determine abuse status.

Conclusions

Self-reported juvenile abuse history may impact response to risperidone augmentation therapy in adults with MDD suboptimally responsive to antidepressants. Abuse status may reduce placebo response and reporting of adverse events.  相似文献   
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