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91.
Previous research has linked higher levels of hopelessness about one's future to violent behavior during adolescence; however, little is known about this relationship over time for adolescents. Using growth curve modeling, we tested the association between future orientation and violent behavior across the high school years of adolescence in a sample of African American youth (n = 681). Variation based on demographic characteristics (i.e., sex, SES, previous violence) was explored. At baseline, differences in violent behavior varied by demographic characteristics. Overall, violent behavior decreased with age. Higher levels of future orientation were associated with greater decreases in violent behavior over time. Demographic characteristics were not associated with change in violent behavior overtime. Our findings suggest that future orientation can act as a promotive factor for at risk African American youth. Interventions that help support the development of future goals and aspirations could play a vital role in violence prevention efforts.  相似文献   
92.
Those charged with assessing and managing threatening communications must utilize risk factors that are behavioral, operational, and reasonably attainable during investigations. This project examined 326 written correspondence cases of an inappropriate, disruptive, or threatening nature that targeted political officials, with the specific goal of identifying written content indicators of problematic approach behavior. Results revealed that subjects who engaged in problematic approach activity toward their targets had more criminal history, past threat assessment activity, familiarity with firearms, past substance use, and indicators of serious mental illness. Approachers were more likely to engage in multiple contact methods, target dispersion, more overall contacts, and prior contact with their target. Numerous content themes were associated with future problematic approach, including longer handwritten correspondence, referencing specific events, making demands, mentioning stressors, focus on personal themes, feeling their rights were violated, and expressing an intention to approach. Harassing, insulting, and threatening language was not related to approach behavior. The implications of these findings are wide-ranging for the practice of threat assessment.  相似文献   
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The DSM-5 Personality and Personality Disorders (PDs) Work Group has recommended a reformulation of the PD section, one component of which is a replacement of specified operational criteria with a prototype matching dimensional rating system. The Work Group indicated that prototype ratings have been demonstrated to have good interrater reliability. No study was cited to support this statement, and a review of the reliability literature does not support this claim. The one study that directly compared the reliability of prototype and DSM-IV criteria counting approaches found the DSM-IV approach was much more reliably applied. The Work Group cited 2 studies supporting the validity of the prototype matching approach, one of which had significant methodological limitations and the other changed the a priori threshold on the PD prototype dimensional rating scale to categorize patients into PD positive and negative groups. The Work Group also cited 2 studies suggesting that prototype matching approaches are preferred by clinicians. Several studies have raised concerns about the adequacy of psychiatric diagnostic evaluations conducted in routine clinical practice thereby raising questions about the value of studies of clinicians' preferences in comparing different diagnostic practices. In conclusion, if the prototype matching dimensional approach described in the DSM-5 draft proposal is adopted, then it will have been adopted with essentially no empirical support demonstrating improved reliability or validity. In fact, there is evidence that reliability will be worse than the DSM-IV approach.  相似文献   
94.
Jordi Fernández has recently responded to my objection that his 'extrospectionist' account of self knowledge posits necessary and sufficient conditions for introspective justification which are neither necessary nor sufficient. I show that my criticisms survive his response unscathed.  相似文献   
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The basolateral complex (BLA) and central nucleus (CEA) of the amygdala play critical roles in associative learning, including Pavlovian conditioning. However, the precise role for these structures in Pavlovian conditioning is not clear. Recent work in appetitive conditioning paradigms suggests that the amygdala, particularly the BLA, has an important role in representing the value of the unconditioned stimulus (US). It is not known whether the amygdala performs such a function in aversive paradigms, such as Pavlovian fear conditioning in rats. To address this issue, Experiments 1 and 2 used temporary pharmacological inactivation of the amygdala prior to a US inflation procedure to assess its role in revaluing shock USs after either overtraining (Experiment 1) or limited training (Experiment 2), respectively. Inactivation of the BLA or CEA during the inflation session did not affect subsequent increases in conditioned freezing observed to either the tone conditioned stimulus (CS) or the conditioning context in either experiment. In Experiment 3, NBQX infusions into the BLA impaired the acquisition of auditory fear conditioning with an inflation-magnitude US, indicating that the amygdala is required for associative learning with intense USs. Together, these results suggest that the amygdala is not required for revaluing an aversive US despite being required for the acquisition of fear to that US.Pavlovian fear conditioning in rats is a behavioral model used to investigate the neurobiology underlying the development and maintenance of fear learning and memory (Grillon et al. 1996; LeDoux 1998, 2000; Bouton et al. 2001; Maren 2001b, 2005; Kim and Jung 2006). In this model, an innocuous conditioned stimulus (CS), such as a tone, is paired with an aversive unconditioned stimulus (US), such as a footshock. After one or more pairings, the rat learns that the CS predicts the US. As a consequence, CS presentations alone elicit a conditioned fear response (CR), which includes increases in heart rate, arterial blood pressure, hypoalgesia, potentiated acoustic startle, stress hormone release, and freezing (somatomotor immobility).The amygdala has been identified as one of the major regions in which fear memories are encoded and stored. Within the amygdala, the basolateral complex of the amygdala (BLA; consisting of the lateral, basolateral, and basomedial nuclei) and the central nucleus of the amygdala (CEA) receive convergent CS and US information and are involved in the acquisition of fear memories (LeDoux 1998, 2000; Fendt and Fanselow 1999; Davis and Whalen 2001; Maren 2001b; Schafe et al. 2001; Fanselow and Gale 2003; Wilensky et al. 2006; Zimmerman et al. 2007). In addition, the CEA has an important role in the expression of fear CRs (Fendt and Fanselow 1999; LeDoux 2000; Davis and Whalen 2001; Maren 2001b; Fanselow and Gale 2003). In support of this, many studies have shown that either permanent or temporary lesions of the BLA or CEA prevent the acquisition and/or expression of fear memories (Helmstetter 1992; Helmstetter and Bellgowan 1994; Campeau and Davis 1995; Maren et al. 1996a,b; Killcross et al. 1997; Muller et al. 1997; Walker and Davis 1997; Cousens and Otto 1998; Maren 1998, 1999, 2001a,b; Wilensky et al. 1999, 2000, 2006; Goosens and Maren 2001, 2003; Nader et al. 2001; Fanselow and Gale 2003; Gale et al. 2004; Koo et al. 2004; Zimmerman et al. 2007).In addition to its role in encoding CS–US associations during conditioning, recent work suggests that the amygdala is also involved in representing properties of the US itself. For example, temporary or permanent lesions of the BLA reduce both decrements in conditioned responding after devaluation of a food US (Hatfield et al. 1996; Killcross et al. 1997; Blundell et al. 2001; Balleine et al. 2003; Everitt et al. 2003; Pickens et al. 2003; Holland 2004) and increments in conditional responding after inflation of a shock US (Fanselow and Gale 2003). Moreover, recent electrophysiological studies in primates indicate that amygdala neurons represent the value of both aversive and appetitive outcomes (Paton et al. 2006; Belova et al. 2007, 2008; Salzman et al. 2007). These studies suggest that one function of the BLA is to represent specific properties of biologically significant events, such as the food or shock USs that are typically used in Pavlovian conditioning paradigms. By this view, the BLA may represent specific sensory properties of USs that shape the nature of learned behavioral responses to the US (Balleine and Killcross 2006) and allow CSs to gain access to the incentive value of the US (Everitt et al. 2003).In contrast to this view, we recently reported that rats with neurotoxic BLA lesions exhibit normal US revaluation after Pavlovian fear conditioning (Rabinak and Maren 2008). In this study, auditory fear conditioning (75 CS–US trials) with a moderate footshock (1 mA) was followed by several exposures (five US-alone trials) to an intense footshock (3 mA) during an inflation session. Both intact rats and rats with BLA lesions exhibit a robust increase in conditional freezing to the auditory CS during a subsequent retention test (Rabinak and Maren 2008). Control experiments suggested that this was due to a revaluation of the US with which the CS was associated, rather than nonassociative sensitization of fear engendered by exposure to intense shock. These data reveal that the BLA may not be necessary for representing properties of shock USs during Pavlovian fear conditioning. To address these issues further, we have examined the consequence of reversible pharmacological manipulations of the amygdala during US inflation on conditional fear responses established with either extensive or limited training.  相似文献   
98.
To investigate maturational plasticity of fluid cognition systems, functional brain imaging was undertaken in healthy 8-19 year old participants while completing visuospatial relational reasoning problems similar to Raven's matrices and current elementary grade math textbooks. Analyses revealed that visuospatial relational reasoning across this developmental age range recruited activations in the superior parietal cortices most prominently, the dorsolateral prefrontal, occipital-temporal, and premotor/supplementary cortices, the basal ganglia, and insula. There were comparable activity volumes in left and right hemispheres for nearly all of these regions. Regression analyses indicated increasing activity predominantly in the superior parietal lobes with developmental age. In contrast, multiple anterior neural systems showed significantly less activity with age, including dorsolateral and ventrolateral prefrontal, paracentral, and insula cortices bilaterally, basal ganglia, and particularly large clusters in the midline anterior cingulate/medial frontal cortex, left middle cingulate/supplementary motor cortex, left insula-putamen, and left caudate. Findings suggest that neuromaturational changes associated with visuospatial relational reasoning shift from a more widespread fronto-cingulate-striatal pattern in childhood to predominant parieto-frontal activation pattern in late adolescence.  相似文献   
99.
Cluster analyzed four variables: school attendance, employment, church attendance, and delinquency, to develop life-style profiles. Data from 218 African-American urban adolescents were used in the study. Five meaningful clusters were retained and subjected to criterion validity analyses using measures of spirituality, participation in a voluntary organization, self-esteem, and friend's substance use. The five clusters were then compared on cigarette, alcohol, marijuana, and hard drug use. The results suggest that a life-style that includes an adaptive compensatory behavior component may be more adaptive than a life-style that does not include compensatory behavior. For example, youths who left high school before graduation but were involved in church reported less alcohol and substance use than youths who left school and were not involved in any meaningful instrumental activity. Implications for intervention and future research on high-risk behaviors are discussed.  相似文献   
100.
We examined whether the orientation-contingent color aftereffect (the McCollough effect) could be mediated by subjective horizontal and vertical structure induced by the perception of transparency. In our experiments, red vertical bars and green horizontal bars were alternated as an adapting stimulus. After adaptation, subjects (n = 6) were asked to adjust the green and red saturation of a test pattern until they obtained a neutral gray. Horizontal and vertical stripes were combined in the test pattern in three different ways: (1) overlapping with a luminance combination that gave rise to a perception of transparent overlays of horizontal and vertical stripes (valid transparency condition), (2) overlapping with luminance combinations that did not induce a perception of transparency (invalid transparency condition) and that appeared more as a patchwork of checks, and (3) presented in adjacent, nonoverlapping areas. Our results showed that the McCollough effect was significantly greater in the valid transparency condition than in the invalid transparency conditions. The effect in the valid transparency condition was nevertheless less strong than was the effect seen with the standard test stimulus made up of nonoverlapping vertical and horizontal stripes. Our results suggest that the McCollough effect can be mediated by the subjective spatial organization (inner representation of vertical and horizontal stripes) that accompanies the perception of transparency in our stimulus.  相似文献   
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