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871.
Sluggish cognitive tempo (SCT) was originally identified as a construct that characterized the inattention problems of some children with attention deficit disorder (ADD). Research has indicated that using SCT symptoms to identify a subset of youth with attention-deficit/hyperactivity disorder, predominately inattentive type (ADHD-IT) may elucidate distinct patterns of impairment and thereby improve the external validity of ADHD subtypes. The objective of the current study was to investigate whether youth with clinically-assessed ADHD-IT and high levels of SCT exhibit unique social and academic impairments. In a clinic-referred sample of youth (N?=?209; 23 % female) aged 6 to 17 years, participants who met criteria for three different groups were identified: ADHD, Combined Type (ADHD-CT; n?=?80), ADHD-IT with low SCT symptoms (n?=?74), and ADHD-IT with high SCT symptoms (n?=?55). These groups were compared on indicators of social and academic functioning while considering the effects of co-occurring internalizing and disruptive behavior disorders. Youth with ADHD-IT high in SCT exhibited uniquely elevated withdrawal, as well as low leadership and low peer-directed relational and overt aggression, which were not accounted for by co-occurring disorders. This high-SCT group was also the only group to have more homework problems than the ADHD-CT group, but only when other disruptive behavior disorders were absent. The distinctiveness of the high-SCT group, which was primarily evident in social as opposed to academic functioning, provides partial support for the external validity and clinical utility of SCT.  相似文献   
872.
Previous work has shown that predictions can be mediated by mechanistic beliefs. The present study shows that such mediation only occurs in the face of contradictory, and not corroborative, evidence. In four experiments, we presented participants with causal statements describing a common-cause structure (E1←C→E2). Then we informed them of the states of C and E1 and asked them to judge the likelihood of E2. In Experiments 1 and 2, we manipulated whether the mechanisms supporting the two effects were the same or different, and whether the evidence presented confirmed or contradicted the participants’ expectations. The relation between the mechanisms only influenced predictions when evidence contradicted the expectations, but not when it was consistent. In Experiments 3 and 4, we used a common-cause structure with identical mechanisms. We manipulated the order in which predictions were made. When confirmatory predictions were made before contradictory predictions, mechanistic modulation was not observed in the confirmatory case. In contrast, the modulation was found when confirmatory predictions were made after contradictory ones. The results support the contradiction hypothesis that causal structure is revised during prediction, but only in the face of unexpected evidence.  相似文献   
873.
When participants answer a test question and then receive feedback of the correct answer, studies have shown that the feedback is more effective when it is delayed by several seconds rather than provided immediately (e.g., Brackbill & Kappy, Journal of Comparative and Physiological Psychology, 55, 14–18, 1962; Schroth, Contemporary Educational Psychology, 17, 78–82, 1992). Despite several demonstrations of this delay-of-feedback benefit, a theoretical explanation for this finding has not yet been developed. The present study tested the hypothesis that brief delays of feedback are beneficial because they encourage anticipation of the upcoming feedback. In Experiment 1, participants answered obscure trivia questions, and before receiving the answer, they rated their curiosity to know the answer. The answer was then provided either immediately or after a 4-s delay. A later final test over the same questions revealed a significant delay-of-feedback benefit, but only for items that had been rated high in curiosity. Experiment 2 replicated this same effect and showed that the delay-of-feedback benefit only occurs when feedback is provided after a variable, unpredictable time duration (either 2, 4, or 8 s) rather than after a constant duration (always 4 s). These findings demonstrate that the delay-of-feedback effect appears to be greatest under conditions in which participants are curious to know the answer and when the answer is provided after an unpredictable time interval.  相似文献   
874.
875.
The apparent contextual variability exhibited by ‘knows’ and its cognates—brought to attention in examples like Keith DeRose’s Bank Case—poses familiar problems for conservative forms of invariantism about ‘knows’. The paper examines and criticises a popular response to those problems, one that involves appeal to so-called ‘pragmatic’ features of language. It is first argued, contrary to what seems to have been generally assumed, that any pragmatic defence faces serious problems with regard to our judgments about retraction. Second, the familiar objection that the pragmatic effects at issue do not seem to be cancellable is considered. Advocates of the pragmatic defence have suggested that cancellability concerns can be dealt with fairly readily. It is shown both that their recent attempts to respond to those concerns, and some other possible attempts, are unsuccessful. Finally, it is argued that the popular relevance-based accounts, found in the work of Jessica Brown, Alan Hazlett, and Patrick Rysiew, fail to provide a satisfactory explanation of our judgments.  相似文献   
876.
We examine a distinctive kind of problem for decision theory, involving what we call discontinuity at infinity. Roughly, it arises when an infinite sequence of choices, each apparently sanctioned by plausible principles, converges to a ‘limit choice’ whose utility is much lower than the limit approached by the utilities of the choices in the sequence. We give examples of this phenomenon, focusing on Arntzenius et al.’s Satan’s apple, and give a general characterization of it. In these examples, repeated dominance reasoning (a paradigm of rationality) apparently gives rise to a situation closely analogous to having intransitive preferences (a paradigm of irrationality). Indeed, the agents in these examples are vulnerable to a money pump set-up despite having preferences that exhibit no obvious defect of rationality. We explore several putative solutions to such problems, particularly those that appeal to binding and to deliberative dynamics. We consider the prospects for these solutions, concluding that if they fail, the examples show that money pump arguments are invalid.  相似文献   
877.
Motivational approaches to depression emphasize the role of dysfunctional motivational dynamics, particularly diminished reward and incentive processes associated with anhedonia. A study examined how anhedonic depressive symptoms, measured continuously across a wide range of severity, influenced the physiological mobilization of effort during a cognitive task. Using motivational intensity theory as a guide, we expected that the diminished incentive value associated with anhedonic depressive symptoms would reduce effort during a “do your best” challenge (also known as an unfixed or self-paced challenge), in which effort is a function of the value of achieving the task’s goal. Using impedance cardiography, two cardiac autonomic responses were assessed: pre-ejection period (PEP), a measure of sympathetic activity and our primary measure of interest, and respiratory sinus arrhythmia (RSA), a measure of parasympathetic activity. As expected, PEP slowed from baseline to task as anhedonic depressive symptoms increased (as measured with the Depression Anxiety Stress Scale), indicating diminished effort-related sympathetic activity. No significant effects appeared for RSA. The findings support motivational intensity theory as a translational model of effort processes in depression and clarify some inconsistent effects of depressive symptoms on effort-related physiology found in past work.  相似文献   
878.
This paper explores an under-theorised phenomenon – the experience of melancholy as an enhancer of happiness. Drawing from philosophy and literature, I define melancholy as an experience that combines the pleasure of feeling sad with sober self-reflection. Despite expectations to the contrary, two potentially positive outcomes of melancholy are identified – insightful pensiveness, and emotional connectedness with loss and pain. These outcomes can enhance happiness as understood in key texts of contemporary Anglo-American philosophy, and, consistent with findings in psychology, also have important implications for wider debates in social policy and welfare practice. First, the pensiveness associated with melancholy can make unique contributions to personal insights, and help develop and fulfill ‘authentic happiness’ and ‘informed desires’. These contributions oppose hedonist accounts of happiness, but are conducive to enhancing happiness properly understood. Second, melancholy can also provide a psychologically safe arena for experiencing loss and pain, where a person can more positively accept the limits of the human condition. This acceptance enhances her happiness, as she is better able to live ‘in the moment’ and so derive satisfaction from her presently-orientated activities and commitments.  相似文献   
879.
Absolute linguistic universals are often justified by cross‐linguistic analysis: If all observed languages exhibit a property, the property is taken to be a likely universal, perhaps specified in the cognitive or linguistic systems of language learners and users. In many cases, these patterns are then taken to motivate linguistic theory. Here, we show that cross‐linguistic analysis will very rarely be able to statistically justify absolute, inviolable patterns in language. We formalize two statistical methods—frequentist and Bayesian—and show that in both it is possible to find strict linguistic universals, but that the numbers of independent languages necessary to do so is generally unachievable. This suggests that methods other than typological statistics are necessary to establish absolute properties of human language, and thus that many of the purported universals in linguistics have not received sufficient empirical justification.  相似文献   
880.
The current study examined dimensions of perfectionism, stress, hopelessness, and suicidality in a sample of adolescent psychiatric patients diagnosed with depression. This study evaluated the unique contribution of perfectionism in predicting suicidality after considering other predictors (i.e., hopelessness, depression) and it also examined the diathesis-stress model of perfectionism and suicide. A sample of 55 adolescents (41 females, mean age = 15.53, 25.5 % ethnic/racial minorities) who were psychiatric patients completed measures including the Child-Adolescent Perfectionism Scale, subjective and objective indices of life stress, daily hassles, depression, hopelessness, suicide ideation, prior attempts and suicide potential. In addition, other informants (i.e., adolescents’ parents) completed a diagnostic interview and an interview assessing major stressful experiences. Socially prescribed perfectionism (i.e., the perception that others require perfection of oneself) predicted concurrent levels of suicide potential and this association with suicide potential held even after controlling for the variances accounted for by depression and hopelessness. Hierarchical regression analyses provided partial support for the diathesis-stress model, that is, socially prescribed perfectionism interacted with daily hassles to predict concurrent suicide potential even after controlling for depression, hopelessness, and prior suicide attempt. Together, these findings suggest that socially prescribed perfectionism acts as a vulnerability factor that is predictive of suicide potential or risk among clinically depressed adolescents.  相似文献   
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