Sleep deprivation in adolescents and adults: changes in affect

The present study investigated the impact of sleep deprivation on several aspects of affective functioning in healthy participants selected from three different developmental periods: early adolescence (ages 10-13), midadolescence (ages 13-16), and adulthood (ages 30-60). Participants completed an affective functioning battery under conditions of sleep deprivation (a maximum of 6.5 hours total sleep time on the first night followed by a maximum of 2 hours total sleep time on the second night) and rest (approximately 7-8 hours total sleep time each night for two consecutive nights). Less positive affect was observed in the sleep-deprived, compared to rested, condition. This effect held for 9 of the 12 positive affect items on the PANAS-C. Participants also reported a greater increase in anxiety during a catastrophizing task and rated the likelihood of potential catastrophes as higher when sleep deprived, relative to when rested. Early adolescents appraised their main worry as more threatening when sleep deprived, relative to when rested. These results support and extend previous research underscoring the adverse affective consequences of sleep deprivation.     

Speak No Evil: Scientists,Responsibility, and the Public Understanding of Science

In this paper, I will discuss the responsibilities that scientists have for ensuring their work is interpreted correctly. I will argue that there are three good reasons for scientists to work to ensure the appropriate communication of their findings. First, I will argue that scientists have a general obligation to ensure scientific research is communicated properly based on the vulnerability of others to the misrepresentation of their work. Second, I will argue that scientists have a special obligation to do so because of the power we as a society invest in them as specialists and professionals. Finally, I will argue that scientists ought to ensure their work is interpreted correctly based on prudential, self-interested considerations. I will conclude by offering suggestions regarding policy considerations.     

Peer-facilitated cognitive dissonance versus healthy weight eating disorders prevention: A randomized comparison

Research supports the efficacy of both cognitive dissonance (CD) and healthy weight (HW) eating disorders prevention, and indicates that CD can be delivered by peer-facilitators, which facilitates dissemination. This study investigated if peer-facilitators can deliver HW when it is modified for their use and extended follow-up of peer-facilitated CD as compared to previous trials. Based on pilot data, we modified HW (MHW) to facilitate peer delivery, elaborate benefits of the healthy-ideal, and place greater emphasis on consuming nutrient dense foods. Female sorority members (N = 106) were randomized to either two 2-h sessions of CD or MHW. Participants completed assessment pre- and post-intervention, and at 8-week, 8-month, and 14-month follow-up. Consistent with hypotheses, CD decreased negative affect, thin-ideal internalization, and bulimic pathology to a greater degree post-intervention. Both CD and MHW reduced negative affect, internalization, body dissatisfaction, dietary restraint, and bulimic pathology at 14 months.     

Accelerating self-motion displays produce more compelling vection in depth

We examined the vection in depth induced when simulated random self-accelerations (jitter) and periodic self-accelerations (oscillation) were added to radial expanding optic flow (simulating constant-velocity forward self-motion). Contrary to the predictions of sensory-conflict theory frontal-plane jitter and oscillation were both found to significantly decrease the onsets and increase the speeds of vection in depth. Depth jitter and oscillation had lesser, but still significant, effects on the speed of vection in depth. A control experiment demonstrated that adding global perspective motion which simulated a constant-velocity frontal-plane self-motion had no significant effect on vection in depth induced by the radial component of the optic flow. These results are incompatible with the notion that constant-velocity displays produce optimal vection. Rather, they indicate that displays simulating self-acceleration can often produce more compelling experiences of self-motion in depth.     

Survey and behavioral measurements of interpersonal trust

Although many studies treat trust as a situational construct, individual differences can be used to study and predict trusting behavior. We report two studies, the first showing the psychometric properties of a new trust inventory (the Propensity to Trust Survey or PTS), the second study validating this inventory using the standard economic task, the Investment Game. The first study utilized online survey data (N > 8000) to show that the PTS scales were reliable and measured broad constructs related to Big Five personality domains. Trust was related to extraversion and negative neuroticism, and trustworthiness was related to agreeableness and conscientiousness. The second study (N = 90) validated the PTS trust scale as a predictor of behavior in the Investment Game. These findings are evidence that trust and trustworthiness are compound personality traits, and that PTS scales are preferable to general Big Five measures for predicting trusting behavior.     

On some limits of hypothetical thinking

Faced with extreme demands, hypothetical thinking runs the danger of total failure. Paradoxical propositions such as the Liar (“I am lying”) provide an opportunity to test it to its limits, while the Liar's nonparadoxical counterpart, the Truthteller (“I am telling the truth”), provides a useful comparison. Two experiments are reported, one with abstract materials (“If I am a knave then I live in Emerald City”) and one with belief-laden materials (a judge says: “If I am a knave then I enjoy pop music”). In both experiments, conditionals with Truthteller-type antecedents were “collapsed” to responses of conditional probability closely resembling estimates of control items. Liar-type antecedents, in contrast, dramatically weakened belief in conditionals in which they were embedded. The results are discussed in the framework of the theory of hypothetical thinking.     

Threat interpretation bias as a vulnerability factor in childhood anxiety disorders

The present study examined threat interpretation biases in children 7-12 years of age with separation, social and generalised anxiety disorders (N=15), non-anxious offspring at risk due to parental anxiety (N=16) and non-anxious controls of non-anxious parents (N=14). Children provided interpretations of ambiguous situations to assess cognitive, emotional and behavioural responses. In comparison with non-anxious control children and at-risk children who did not differ from each other, anxious children reported stronger negative emotion and less ability to influence ambiguous situations. These results suggest that threat interpretation bias may be a cognitive factor associated with ongoing childhood anxiety but not a vulnerability factor associated with parental anxiety.     

Transdiagnostic emotion regulation processes in bipolar disorder and insomnia

Research and treatment have traditionally adopted a 'disorder-focused' approach by targeting one specific disorder, aiming to understanding its cause, maintenance and treatment. The aim of the present study was to contribute to the burgeoning interest in examining common, or 'transdiagnostic,' processes across disorders. Three candidate transdiagnostic processes involved in emotion regulation - rumination, worry, and automatic negative thoughts - were examined in euthymic bipolar I disorder (n=21) and insomnia (n=19), and a non-clinical control group (n=20). Rumination and worry were endorsed to a larger degree by the bipolar and insomnia groups compared to the control group. However, while the bipolar group had more negative automatic thoughts than the control group, there were no significant differences in negative automatic thoughts between the bipolar and insomnia groups or the insomnia and control groups. These results suggested that rumination and worry, but not negative automatic thoughts, might be common across bipolar disorder and insomnia. However, these findings no longer remained significant when current symptoms of anxiety and depression were controlled for. Prospective and experimental studies are needed to test the extent to which these processes contribute to the etiology or maintenance of insomnia and bipolar disorder.     

When can we say 'if'?

In this study, we focus on the conditions which permit people to assert a conditional statement of the form 'if p then q' with conversational relevance. In a broadly decision-theoretic approach, also drawing on hypothetical thinking theory [Evans, J. St. B. T. (2007). Hypothetical thinking: Dual processes in reasoning and judgement. Hove, UK: Psychology Press.], we predicted that conditional tips and promises would appear more useful and persuasive and be more likely to encourage an action p when (a) the conditional link from p to q was stronger, (b) the cost of the action p was lower and (c) the benefit of the consequence q was higher. Similarly, we predicted that conditional warnings and threats would be seen as more useful and persuasive and more likely to discourage an action p when (a) the conditional link from p to q was stronger, (b) the benefit of the action p was lower and (c) the cost of the consequence q was higher. All predictions were strongly confirmed, suggesting that such conditionals may best be asserted when they are of high relevance to the goals of the listener.     

Further evaluation of a brief, intensive teacher-training model

The purpose of this study was to further evaluate the outcomes of a model program that was designed to train current teachers of children with autism. Nine certified special education teachers participating in an intensive 5-day summer training program were taught a relatively large number of specific skills in two areas (preference assessment and direct teaching). The teachers met the mastery criteria for all of the skills during the summer training. Follow-up observations up to 6 months after training suggested that the skills generalized to their classrooms and were maintained for most teachers with brief feedback only.