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291.
Clinical and epidemiologic studies have established that posttraumatic stress disorder (PTSD) is highly comorbid with other mental disorders. However, such studies have largely relied on adults' retrospective reports to ascertain comorbidity. The authors examined the developmental mental health histories of adults with PTSD using data on mental disorders assessed across the first 3 decades of life among members of the longitudinal Dunedin Multidisciplinary Health and Development Study; 100% of those diagnosed with past-year PTSD and 93.5% of those with lifetime PTSD at age 26 had met criteria for another mental disorder between ages 11 and 21. Most other mental disorders had first onsets by age 15. Of new cases of PTSD arising between ages 26 and 32, 96% had a prior mental disorder and 77% had been diagnosed by age 15. These data suggest PTSD almost always develops in the context of other mental disorders. Research on the etiology of PTSD may benefit from taking lifetime developmental patterns of comorbidity into consideration. Juvenile mental-disorder histories may help indicate which individuals are most likely to develop PTSD in populations at high risk of trauma exposure.  相似文献   
292.
Chimpanzees provide help to unrelated individuals in a broad range of situations. The pattern of helping within pairs suggests that contingent reciprocity may have been an important mechanism in the evolution of altruism in chimpanzees. However, correlational analyses of the cumulative pattern of interactions over time do not demonstrate that helping is contingent upon previous acts of altruism, as required by the theory of reciprocal altruism. Experimental studies provide a controlled approach to examine the importance of contingency in helping interactions. In this study, we evaluated whether chimpanzees would be more likely to provide food to a social partner from their home group if their partner had previously provided food for them. The chimpanzees manipulated a barpull apparatus in which actors could deliver rewards either to themselves and their partners or only to themselves. Our findings indicate that the chimpanzees’ responses were not consistently influenced by the behavior of their partners in previous rounds. Only one of the 11 dyads that we tested demonstrated positive reciprocity. We conclude that contingent reciprocity does not spontaneously arise in experimental settings, despite the fact that patterns of behavior in the field indicate that individuals cooperate preferentially with reciprocating partners.  相似文献   
293.
We conducted two separate, exploratory studies to evaluate the differences between the supervision of wraparound (in-home) and outpatient (office) child treatment interventions. Study one (n = 96) examined the structure and norms of supervision between groups as well as rates of general disclosure to direct supervisors. Study two (n = 116) specifically examined the frequency of child abuse and neglect encountered in each intervention setting, and the level of disclosure in supervision of these mandatory reporting events. Findings from the first study suggest that wraparound clinicians received significantly less individual supervision and colleague consultation than their office-based counterparts. Additionally, wraparound clinicians were significantly more likely to withhold information about client cases from their direct supervisors. In the second study, wraparound clinicians endorsed significant increases for observed child abuse, observed child neglect, and verbally reported child neglect compared to their office-based counterparts. In regards to mandatory reporting issues with children, wraparound clinicians were found to be significantly less likely to disclose issues pertaining to child neglect to their direct supervisors than office-based clinicians. Our studies show preliminary evidence for a needed increase of individual supervision in wraparound practice, in addition to a greater focus on clinician disclosures related to incidents of child abuse and neglect.  相似文献   
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295.
A prominent hypothesis holds that ‘sticky’ attention early in life in children with autism spectrum disorder (ASD) limits their ability to explore and learn about the world. Under this hypothesis, the core clinical symptoms of ASD – restricted interests, repetitive behaviors and impaired social/communication abilities – could all result from impaired attentional disengagement during development. However, the existence of disengagement deficits in children with ASD is controversial, and a recent study found no deficit in 5‐ to 12‐year‐olds with ASD. Nonetheless, the possibility remains that disengagement is impaired earlier in development in children with ASD, altering their developmental trajectory even if the attentional deficit itself is remediated or compensated for by the time children with ASD reach school age. Here, we tested this possibility by characterizing attentional disengagement in a group of toddlers just diagnosed with ASD (age 21 to 37 months). We found strikingly similar performance between the ASD and age‐matched typically developing (TD) toddlers, and no evidence of impaired attentional disengagement. These results show that even at a young age when the clinical symptoms of ASD are first emerging, disengagement abilities are intact. Sticky attention is not a fundamental characteristic of ASD, and probably does not play a causal role in its etiology.  相似文献   
296.
Individuals with early-emerging conduct problems are likely to become parents who expose their children to considerable adversity. The current study tested the specificity of and alternative explanations for this trajectory. The sample included 246 members of a prospective, 30-year cohort study and their 3-year-old children. Parents who had a history of conduct disorder were specifically at elevated risk for socioeconomic disadvantage and relationship violence, but suboptimal parenting and offspring temperament problems were common to parents with any history of disorder. Recurrent disorder, comorbidity, and adversity in the family of origin did not fully account for these findings. The cumulative consequences of early-onset conduct disorder and assortative mating for antisocial behavior may explain the long-term effects of conduct disorder on young adult functioning.  相似文献   
297.
Every environment contains infinite potential features and correlations among features, or patterns. Detecting valid and learnable patterns in one environment is beneficial for learners because doing so lends predictability to new environments where the same or analogous patterns recur. However, some apparent correlations among features reflect spurious patterns, and attempting to learn the latter costs time and resources with no advantage to the learner. Thus, an efficient learner in a complex environment needs to devote more attention to input that reflects a real and learnable pattern than to input that reflects a spurious or ultimately unlearnable pattern. However, in order to achieve such efficiency in the absence of external feedback, learners need to have an implicit metric of their own learning progress. Do human infants have such a metric? Data from two experiments demonstrate that 17‐month‐olds attend longer to learnable vs. unlearnable linguistic grammars, taking more trials to habituate and more overall time to habituate for grammars in which a valid generalization over input stimuli can be made. These data provide the first evidence that infants have an implicit metric of their own learning progress and preferentially direct their attention to learnable aspects of their environment.  相似文献   
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299.
In the present experiment, the authors investigated the idea that within-session changes in operant response rates occur because subjects sensitize and then habituate to the reinforcer. If that is true, then altering an aspect of the reinforcer within the session should alter the observed within-session responding. The authors tested that idea by having rats press a lever for 2 food-pellet reinforcers delivered by a variable-interval 120-s schedule during 60-min baseline sessions. In treatment conditions, the magnitude of the reinforcer was halved (1 pellet) or doubled (4 pellets) 10, 20, 30, 40, or 50 min into the session. That magnitude of reinforcement then remained in effect for the rest of the session. Altering reinforcer magnitude altered the rates of responding within the session in a fashion consistent with the habituation explanation, that is, response rates increased, relative to baseline, when the magnitude of reinforcement was increased. They decreased when the magnitude was decreased. Those results were seemingly inconsistent with the competing idea that within-session decreases in responding rates are produced by satiation.  相似文献   
300.
An interest in early identification of youth who may be at risk of psychopathy has generated measures for age-appropriate screening and assessment. This study examines the structural, concurrent, and divergent validity of the Psychopathy Content Scale, a 20-item self-report instrument derived from the Millon Adolescent Clinical Inventory (MACI). Data for 481 youths who had taken the MACI, the Child Behavior Checklist Youth Self-Report (YSR), and the Massachusetts Youth Screening Instrument, Second Version (MAYSI-2), were analyzed. Results showed that the PCS is best described by a two-factor model and that analyses of the two factors offer limited support for convergent and divergent validity. High scores on both factors were associated with high YSR and MAYSI-2 scales, suggesting that the measure identified youth who were distressed on several measures of emotional, psychological, and behavioral disorder.  相似文献   
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