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231.
Children who display symptoms of Attention Deficit Hyperactivity Disorder (ADHD) in classrooms are reputed to display fewer symptoms in one-on-one interaction. We tested this hypothesis with children who received tutoring for reading and behavior problems. We selected 30 children whose teacher-rated ADHD symptoms fit a pattern consistent with DSM criteria for the diagnosis. Teachers rated the frequency of symptoms in classrooms before and after tutoring. Tutors rated the frequency of the same behaviors during individual tutoring sessions. Children's ADHD symptoms, as well as oppositional symptoms, were significantly lower in the tutoring sessions than in the classrooms. The effect sizes for the difference between behavior in classrooms and in individual tutoring ranged from 0.7 to 2.5 standard deviations. These effect sizes appear as large as those reported for the effect of stimulant medication on ADHD symptoms. All 30 children at preintervention fit the pattern for ADHD using teachers' ratings of classroom behavior; 87% of them did not meet those DSM criteria using tutors' ratings of behavior in individual sessions. The confound of different raters for the two different settings must be resolved by another study with a new design.  相似文献   
232.
Drug addicts make poor decisions. These decision-making deficits have been modeled in addicts and laboratory animals using reversal-learning tasks. However, persistent reversal-learning impairments have been shown in rats and monkeys only after noncontingent cocaine injections. Current thinking holds that to represent the human condition effectively, animal models of addiction must utilize self-administration procedures in which drug is earned contingently; thus, it remains unclear whether reversal-learning deficits caused by noncontingent cocaine exposure are relevant to addiction. To test whether reversal learning deficits are caused by contingent cocaine exposure, we trained rats to self-administer cocaine, assessed cue-induced cocaine seeking in extinction tests after 1 and 30 d of withdrawal, and then tested for reversal learning more than a month later. We found robust time-dependent increases in cue-induced cocaine seeking in the two extinction tests (incubation of craving) and severe reversal-learning impairments.  相似文献   
233.
Philosophers, scientists, and other researchers have increasingly characterized humanity as having reached an epistemic and technical stage at which “we can control our own evolution.” Moral–philosophical analysis of this outlook reveals some problems, beginning with the vagueness of “we.” At least four glosses on “we” in the proposition “we, humanity, control our evolution” can be made: “we” is the bundle of all living humans, a leader guiding the combined species, each individual acting severally, or some mixture of these three involving a market interpretation of future evolutionary processes. While all of these glosses have difficulties under philosophical analysis, how we as a species handle our fate via technical developments is all-important. I propose our role herein should be understood as other than controllers of our evolution.  相似文献   
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Despite the extensive evaluation of school-based interventions for bullying, victimization remains a significant problem in schools. Bullying victimization is significantly predicted by contextual (school-related) factors. As a consequence whole-school programs have been commonly used to prevent and reduce bullying victimization. Evidence also points to individual risk factors (such as emotional distress) in predicting victimization, yet programs to prevent bullying victimization by changing these individual risks are far less developed. Few studies have approximated “real-world” implementation conditions in their trials. The current effectiveness trial evaluated the combination of a whole-school program designed to prevent bullying perpetration and victimization together with a targeted intervention for at-risk students, teaching them individual and dyadic strategies to reduce their anxiety and manage victimization, allowing schools some latitude to implement programs as they typically would. Students from Grades 3 and 4 (N = 8,732) across 135 schools were randomly assigned to one of four conditions: combined intervention; whole-school intervention only; individual intervention only; and care as usual. Victimization decreased significantly and similarly across all four conditions at 12 and 24 months following baseline. Similar reductions and failure to discriminate conditions were found on other key constructs: anxiety; bullying perpetration; and depression. Possible reasons for the failure to demonstrate victimization prevention differences and lessons learned from this large, effectiveness trial are considered.  相似文献   
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The multimillennial philosophical discussion about life after death has received a recent boost in the prospect of immortality attained via technologies. In this newer version, humans generally are considered mortal but may develop means of making themselves immortal. If “immortal” means not mortal, thus existing for infinity, and if the proposed infinite‐existing entity is material, it must inhabit an infinite material universe. If the proposed entity is not material, there must be means by which it can shed its material substance and exist nonmaterially. The article examines arguments for how an infinite life would be possible given current physical understanding. The paper considers a Pascalian‐style wager weighing the likelihood of adjusting to existence wholly within a finite universe versus betting on there being some way to construe the universe(s) as a viable medium for infinite beings. Conclusion: the case for a finite being to exist infinitely has little viable support.  相似文献   
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In sign languages, the task of communicating a shape involves drawing in the air with one moving hand (Method One) or two (Method Two). Since the movement path is iconic, method choice might be based on the shape. In the present studies we aimed to determine whether geometric properties motivate method choice. In a study of 17 deaf signers from six countries, the strongest predictors of method choice were whether the shape has any curved edges (Method One), and whether the shape is symmetrical across the Y‐axis (Method Two), where the default was Method One. In a second study of ASL dictionary entries for which the movement path of the sign is iconic of an entity's shape, the same predictors surfaced. These tendencies are captured in the Lexical Drawing Principle, which is coherent with biological constraints on movement in general. Drawing in the air with two hands, however, is costly, both cognitively and biomechanically. Furthermore, it distinguishes signers from non‐signers, who draw shapes with only one hand. Signers assume this extra cost in the lexicon because of the enhanced iconicity the possibility of two hands offers; they assume it in drawing shapes in the air because they apply the same linguistic principle they use in the lexicon. Additionally, having a choice of methods allows the signer to benefit from over‐specification in providing redundant information about the shape, enhancing comprehensibility and resolving ambiguity.  相似文献   
239.
    
Background and Objectives: Chronically stressed individuals report deficits spanning cognitive and emotional functioning. However, limitations to clinical populations and measures of stress have impeded the generalisability and scope of results. This study investigated whether chronic stress predicted cognitive and emotional functioning, and whether these relationships differed between males and females, in a large representative sample of healthy participants.

Design: Cross-sectional study.

Method: 1883 healthy adults sampled from the Brain Resource International Database reported stress using the 21-item Depression Anxiety Stress Scales. Participants then completed a cognitive and emotional assessment battery (IntegNeuro), as well as questionnaires related to sleep, emotional functioning, and self-regulation.

Results: In contrast to previously reported results, chronic stress did not predict cognitive functioning. However, higher stress predicted a greater negativity bias and poorer social skills, confirming previous research identifying these links.

Conclusions: Cognitive deficits related to stress are absent in healthy participants when stress is measured using the 21-items Depression Anxiety Stress Scales. Identifying how chronic stress is associated with aspects of emotional functioning can lead to personalized interventions for individuals to better manage the negative outcomes resulting from stress.  相似文献   

240.
    
ABSTRACT

Despite growing evidence of the repeated nature of traumatic brain injury (TBI) in women experiencing intimate partner violence (IPV), there is no theoretical model depicting TBIs as a cyclical process throughout a lifetime. Situational analysis methodology was used on interviews with 10 women who self-reported passing out from being hit in the head during an episode of IPV to create a theoretical model depicting the cycle of transmission of TBI. We define the cycle of transmission of TBI as the way that women experience multiple TBIs over the course of their lifetime and how TBI can be perpetuated in a family or community. The cycle begins in childhood or adolescence, when women receive a TBI from abuse, sports, or motor vehicle accident. They enter into abusive relationships with men who are also described as living with a TBI and the women receive other TBIs during this relationship. With repeating head trauma, women described increasing TBI symptoms: problems with memory, cognition, executive functioning, depression, and concentration. If they do seek help, they must choose between healthcare and protective shelter. With either choice, the element of instability could be introduced and the cycle of transmission continues. This theoretical model shows that it is necessary to move beyond individual behaviors to think about how TBIs are transmitted through communities and how untreated symptoms can impact help-seeking behavior and perpetuate other risk factors for receiving a TBI.  相似文献   
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