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71.

In hybrid foraging, observers search visual displays for multiple instances of multiple target types. In previous hybrid foraging experiments, although there were multiple types of target, all instances of all targets had the same value. Under such conditions, behavior was well described by the marginal value theorem (MVT). Foragers left the current “patch” for the next patch when the instantaneous rate of collection dropped below their average rate of collection. An observer’s specific target selections were shaped by previous target selections. Observers were biased toward picking another instance of the same target. In the present work, observers forage for instances of four target types whose value and prevalence can vary. If value is kept constant and prevalence manipulated, participants consistently show a preference for the most common targets. Patch-leaving behavior follows MVT. When value is manipulated, observers favor more valuable targets, though individual foraging strategies become more diverse, with some observers favoring the most valuable target types very strongly, sometimes moving to the next patch without collecting any of the less valuable targets.

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72.

Diverse adaptive visual processing mechanisms allow us to complete visual search tasks in a wide visual photopic range (>0.6 cd/m2). Whether search strategies or mechanisms known from this range extend below, in the mesopic and scotopic luminance spectra (<0.6 cd/m2), has yet to be addressed. Based on a study that addressed simple target discrimination in luminance environments using contrast-dependent behavioral efficiency functions, we assessed visual search in more complex-feature and conjunction-search paradigms. The results verify the previously reported deficiency windows defined by an interaction of base luminance and luminance contrast for more complex visual-search tasks. Based on significant regression analyses, a more precise definition of the magnitude of contribution of different contrast parameters. Characterized feature search patterns had approximately a 2.5:1 ratio of contribution from the Michelson contrast property relative to Weber contrast, whereas the ratio was approximately 1:1 in a serial-search condition. The results implicate near-complete magnocellular isolation in a visual-search paradigm that has yet to be demonstrated. Our analyses provide a new method of characterizing visual search and the first insight in its underlying mechanisms in luminance environments in the low mesopic and scotopic spectra.

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73.
Emotion dysregulation, the pervasive difficulty managing negative emotions, is a core problem across mood and anxiety disorders. Anger, shame, and disgust are particularly problematic emotions, impacting both disorder severity and treatment outcome. We previously found that a 16-week dialectical behavior therapy skills training group (DBT-ST) was superior to an activities-based support group (ASG) in decreasing emotion dysregulation in 44 adults with high emotion dysregulation who met diagnostic criteria for an anxiety or depressive disorder. We presently examine these participants’ changes in anger, shame, disgust, and distress using self-reports collected over 6 months during and after treatment. Hierarchical linear modeling analyses show that DBT-ST was superior to ASG in decreasing anger suppression (d = 0.93) and distress (d = 1.04). Both conditions significantly reduced shame, disgust propensity, and disgust sensitivity, but neither was superior for these outcomes. The treatments did not significantly reduce anger expression. Mediation analyses suggest that condition indirectly influenced 4-month anger suppression, shame, and distress through its effect on 2-month emotion dysregulation. These findings suggest that DBT-ST is efficacious for certain problematic emotions and distress in depressed and anxious adults and that common factors may account for some, but not all, of its benefits.  相似文献   
74.
The sex difference in jealousy is an effect that has generated significant controversy in the academic literature (resulting in two meta-analyses that reached different conclusions on the presence or absence of the effect). In this study, we had a team of researchers from different theoretical perspectives use identical protocols to test whether the sex difference in jealousy would occur across many different samples (while testing whether mate value would moderate the effect). In our samples, we found the sex difference in jealousy to occur using both forced choice and continuous measures, this effect appeared in several different settings, and, we found that mate value moderated participant responses. The results are discussed in light of the controversy surrounding the presence of the effect.  相似文献   
75.
The present study examined persistence and relapse of reinforced behavioral variability in pigeons. Pigeons emitted four‐response sequences across two keys. Sequences produced food according to a lag schedule, in which a response sequence was followed by food if it differed from a certain number of previous sequences. In Experiment 1, food was delivered for sequences that satisfied a lag schedule in both components of a multiple schedule. When reinforcement was removed for one component (i.e., extinction), levels of behavioral variability decreased for only that component. In Experiment 2, food was delivered for sequences satisfying a lag schedule in one component of a multiple schedule. In the other component, food was delivered at the same rate, but without the lag variability requirement (i.e., yoked). Following extinction, levels of behavioral variability returned to baseline for both components after response‐independent food delivery (i.e., reinstatement). In Experiment 3, one group of pigeons responded on a lag variability schedule, and the other group responded on a lag repetition schedule. For both groups, levels of behavioral variability increased when alternative reinforcement was suspended (i.e., resurgence). In each experiment, we observed some evidence for extinction‐induced response variability and for variability as an operant dimension of behavior.  相似文献   
76.
The CaR-FA-X model (Williams et al., 2007), or capture and rumination (CaR), functional avoidance (FA), and impaired executive control (X), is a model of overgeneral autobiographical memory (OGM). Two mechanisms of the model, rumination and executive control, were examined in isolation and in interaction in order to investigate OGM over time. Across two time points, six months apart, a total of 149 adolescents (13–16 years) completed the minimal-instruction autobiographical memory test, a measure of executive control with both emotional and nonemotional stimuli, and measures of brooding rumination and reflective pondering. The results showed that executive control for emotional information was negatively associated with OGM, but only when reflective pondering levels were high. Therefore, in the context of higher levels of reflective pondering, greater switch costs (i.e., lower executive control) when processing emotional information predicted a decrease in OGM over time.  相似文献   
77.
Suicide is a leading cause of death among youth worldwide, and depressed adolescents are at a significantly elevated risk to report suicidal ideation, planning, and attempts. Peer victimization is a robust predictor of adolescent suicidal thoughts and behaviors (STBs), but little research has focused on why bullying leads to suicidal thoughts and behaviors. To address this empirical gap, we recruited 340 (246 female) depressed adolescents ages 13–19 (M = 15.59, SD = 1.41) within 48 h of admission for acute psychiatric treatment. At the initial assessment, participants were administered clinical interviews characterizing psychopathology, nonsuicidal self-injury, and STBs (ideation, plans, and attempts). Further, they completed questionnaires assessing 3 forms of victimization (overt, relational, and reputational), recent risky behavior engagement, and psychiatric symptom severity. Controlling for internalizing symptoms and age, overt and reputational bullying were associated with more frequent past month suicide attempts, but not suicide ideation. Past month risky behavior engagement, but not NSSI, mediated the relation between victimization and attempts. However, sex differences revealed that this effect only held for males whereas bullying was directly associated with suicide attempts among females. In contrast, overt and relational bullying were non-linearly associated with suicide plans, and these relations were not mediated by risky behaviors or NSSI. Results highlight the complex network of factors that lead victimized adolescents to engage in STBs and may inform targeted suicide prevention and intervention programs.  相似文献   
78.
79.
Despite a large and growing literature on workplace discrimination, there has been a myopic focus on the direct relationships between discrimination and a common set of outcomes. The aim of this meta‐analytic review was both to challenge and advance current understanding of workplace discrimination and its associations with outcomes by identifying the pathways through which discrimination affects outcomes, examining boundary conditions to explain when discrimination is most harmful for employees, and exploring a potential third variable explanation for discrimination–outcome relationships. Mediation tests indicated that workplace discrimination is associated with employee outcomes through both job stress and justice. Moderator analyses showed that discrimination appears to be most detrimental when it is observed rather than personally experienced, interpersonal rather than formal, and measured broadly rather than specifically. We also found that discrimination–outcome relationships differ across work and nonwork contexts and as a function of the social identity targeted by discrimination. Discrimination generally explained meaningful incremental variance in outcomes after controlling for the effects of negative affectivity, but the relationships between discrimination and health were substantially decreased. We conclude by offering a constructive critique of the empirical discrimination literature and by detailing an agenda for future research.  相似文献   
80.
Bioethicists invoke a duty to rescue in a wide range of cases. Indeed, arguably, there exists an entire medical paradigm whereby vast numbers of medical encounters are treated as rescue cases. The intuitive power of the rescue paradigm is considerable, but much of this power stems from the problematic way that rescue cases are conceptualized—namely, as random, unanticipated, unavoidable, interpersonal events for which context is irrelevant and beneficence is the paramount value. In this article, I critique the basic assumptions of the rescue paradigm, reframe the ethical landscape in which rescue obligations are understood, and defend the necessity and value of a wider social and institutional view. Along the way, I move back and forth between ethical theory and a concrete case where the duty to rescue has been problematically applied: the purported duty to regularly return incidental findings and individual research results in genomic and genetic research.  相似文献   
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