The purpose of this study was to examine the effects of sleep deprivation on impulsive behavior. Patients with impulse control disorders often report sleep problems, and sleep deprivation even in healthy individuals impairs cognition, decision-making, and perhaps impulse control. To characterize the effects of sleep loss on specific forms of impulsive behavior, we tested the effects of overnight, monitored sleep deprivation on measures of impulsivity and cognition in healthy volunteers. Ten men and ten women completed two 24 h sessions in random order, in which they were either allowed to sleep normally or remained awake all night. At 8:30 am and 6:15 pm on the day after sleep or no sleep, participants were tested on the Balloon Analogue Risk Task (BART), the Experiential Discounting Task, the Adjusting Amount Delay and Probability Discounting Task, and the Stop Task. Participants also completed mood questionnaires and the Automated Neuropsychological Assessment Matrix (ANAM) throughout the course of the day. Sleep deprivation did not affect most of the measures of impulsive behavior. However, on the BART, sleep deprivation decreased risk taking in women, but not men. Sleep deprivation produced expected increases in subjective fatigue, and impaired performance on measures of attention and cognitive efficiency on the ANAM. The results indicate that sleep deprivation does not specifically increase impulsive behaviors but may differentially affect risk taking in men and women.

As a clinical condition, boredom is an emotional state, widespread among young people, characterized by unpleasant feelings, lack of motivation, and low physiological arousal in which the level of stimulation is perceived as unsatisfactorily low. Boredom is an important emotional state due to its spread among young people. Recent research has mainly studied the complex connection between boredom and leisure-time experiences, which may be involved in adolescents' risk-taking behaviors. The current study aims to investigate boredom proneness, conceived as a personality trait, in adolescents' free time, and its involvement in more extreme behaviors, such as binge drinking and addictive Internet use, which may represent ways to cope with the search for additional stimuli. Data from a large sample of Italian adolescents ( n = 478, aged between 14 years and 19 years, M = 16.31, SD = 1.47) revealed significant differences between low-boredom and high-boredom subjects. Both girls and boys with high boredom proneness used technology more, engaged less in hobbies and activities such as sports, more frequently consumed strong drinks and binge drank, and were more at risk of Internet addiction than non-bored adolescents. These findings suggest a hypothetical risk profile linked to boredom proneness in adolescence. The results are discussed in light of the literature from a psychosocial and clinical perspective.

The purpose of the present study was to examine whether the Big Five personality factors could predict who thrives or chokes under pressure during decision-making. The effects of the Big Five personality factors on decision-making ability and performance under social (Experiment 1) and combined social and time pressure (Experiment 2) were examined using the Big Five Personality Inventory and a dynamic decision-making task that required participants to learn an optimal strategy. In Experiment 1, a hierarchical multiple regression analysis showed an interaction between neuroticism and pressure condition. Neuroticism negatively predicted performance under social pressure, but did not affect decision-making under low pressure. Additionally, the negative effect of neuroticism under pressure was replicated using a combined social and time pressure manipulation in Experiment 2. These results support distraction theory whereby pressure taxes highly neurotic individuals' cognitive resources, leading to sub-optimal performance. Agreeableness also negatively predicted performance in both experiments.

Many phenomena in judgment and decision making are often attributed to the interaction of 2 systems of reasoning. Although these so-called dual process theories can explain many types of behavior, they are rarely formalized as mathematical or computational models. Rather, dual process models are typically verbal theories, which are difficult to conclusively evaluate or test. In the cases in which formal (i.e., mathematical) dual process models have been proposed, they have not been quantitatively fit to experimental data and are often silent when it comes to the timing of the 2 systems. In the current article, we present a dynamic dual process model framework of risky decision making that provides an account of the timing and interaction of the 2 systems and can explain both choice and response-time data. We outline several predictions of the model, including how changes in the timing of the 2 systems as well as time pressure can influence behavior. The framework also allows us to explore different assumptions about how preferences are constructed by the 2 systems as well as the dynamic interaction of the 2 systems. In particular, we examine 3 different possible functional forms of the 2 systems and 2 possible ways the systems can interact (simultaneously or serially). We compare these dual process models with 2 single process models using risky decision making data from Guo, Trueblood, and Diederich (2017). Using this data, we find that 1 of the dual process models significantly outperforms the other models in accounting for both choices and response times. (PsycINFO Database Record

Complex dynamic behaviour involves reciprocal influences between emotion and cognition. On the one hand, emotion is a

Appropriate interpretation of pleasurable, rewarding experiences favors decisions that enhance survival. Conversely, dysfunctional affective brain processing can lead to life-threatening risk behaviors (e.g., addiction) and emotion imbalance (e.g., mood disorders). The state of sleep deprivation continues to be associated with maladaptive emotional regulation, leading to exaggerated neural and behavioral reactivity to negative, aversive experiences. However, such detrimental consequences are paradoxically aligned with the perplexing antidepressant benefit of sleep deprivation, elevating mood in a proportion of patients with major depression. Nevertheless, it remains unknown how sleep loss alters the dynamics of brain and behavioral reactivity to rewarding, positive emotional experiences. Using functional magnetic resonance imaging (fMRI), here we demonstrate that sleep deprivation amplifies reactivity throughout human mesolimbic reward brain networks in response to pleasure-evoking stimuli. In addition, this amplified reactivity was associated with enhanced connectivity in early primary visual processing pathways and extended limbic regions, yet with a reduction in coupling with medial frontal and orbitofrontal regions. These neural changes were accompanied by a biased increase in the number of emotional stimuli judged as pleasant in the sleep-deprived group, the extent of which exclusively correlated with activity in mesolimbic regions. Together, these data support a view that sleep deprivation not only is associated with enhanced reactivity toward negative stimuli, but imposes a bidirectional nature of affective imbalance, associated with amplified reward-relevant reactivity toward pleasure-evoking stimuli also. Such findings may offer a neural foundation on which to consider interactions between sleep loss and emotional reactivity in a variety of clinical mood disorders.

Sleep deprivation reduces regional cerebral metabolism within the prefrontal cortex, the brain region most responsible for higher-order cognitive processes, including judgment and decision making. Accordingly, we hypothesized that two nights of sleep loss would impair decision making quality and lead to increased risk-taking behavior on the Iowa Gambling Task (IGT), which mimics real-world decision making under conditions of uncertainty. Thirty-four healthy participants completed the IGT at rested baseline and again following 49.5 h of sleep deprivation. At baseline, volunteers performed in a manner similar to that seen in most samples of healthy normal individuals, rapidly learning to avoid high-risk decks and selecting more frequently from advantageous low-risk decks as the game progressed. After sleep loss, however, volunteers showed a strikingly different pattern of performance. Relative to rested baseline, sleep-deprived individuals tended to choose more frequently from risky decks as the game progressed, a pattern similar to, though less severe than, previously published reports of patients with lesions to the ventromedial prefrontal cortex. Although risky decision making was not related to participant age when tested at rested baseline, age was negatively correlated with advantageous decision making on the IGT, when tested following sleep deprivation (i.e. older subjects made more risky choices). These findings suggest that cognitive functions known to be mediated by the ventromedial prefrontal cortex, including decision making under conditions of uncertainty, may be particularly vulnerable to sleep loss and that this vulnerability may become more pronounced with increased age.

Recent evidence suggests that sleep deprivation leads to suboptimal decision-making on the Iowa Gambling Task (IGT), a pattern that appears to be unaffected by moderate doses of caffeine. It is not known whether impaired decision-making could be reversed by higher doses of caffeine or by other stimulant countermeasures, such as dextroamphetamine or modafinil. Fifty-four diurnally active healthy subjects completed alternate versions of the IGT at rested baseline, at 23 and 46 h awake, and following a night of recovery sleep. After 44 h awake, participants received a double-blind dose of caffeine (600 mg), dextroamphetamine (20 mg), modafinil (400 mg), or placebo. At baseline, participants showed a normal pattern of advantageous performance, whereas both sleep-deprived sessions were associated with suboptimal decision-making on the IGT. Following stimulant administration on the second night of sleep deprivation, groups receiving caffeine, dextroamphetamine, or modafinil showed significant reduction in subjective sleepiness and improvement in psychomotor vigilance, but decision-making on the IGT remained impaired for all stimulants and did not differ from placebo. Decision-making returned to normal following recovery sleep. These findings are consistent with prior research showing that sleep deprivation leads to suboptimal decision-making on some types of tasks, particularly those that rely heavily on emotion processing regions of the brain, such as the ventromedial prefrontal cortex. Moreover, the deficits in decision-making were not reversed by commonly used stimulant countermeasures, despite restoration of psychomotor vigilance and alertness. These three stimulants may restore some, but not all, aspects of cognitive functioning during sleep deprivation.

INTRODUCTION: Recent research indicates that sleep deprivation impairs decision making. However, it is unknown to what extent such deficits are exacerbated in a dose-response manner by increasing levels of sleepiness, and the extent to which such sleep-loss-induced deficits can be reversed by caffeine. METHODS: At three time points, 26 healthy subjects completed alternate forms of the Iowa Gambling Task (IGT): rested baseline, 51 h awake, and 75 h awake. Every 2 h each night, 12 volunteers also received 4 200-mg doses of caffeine, with the last dose occurring 3 h prior to the IGT. RESULTS: At baseline, volunteers readily learned to avoid disadvantageous high-risk card decks while progressively choosing more frequently from advantageous low-risk card decks. When sleep deprived, however, these same subjects showed impaired performance, choosing more frequently from the disadvantageous high-risk card decks, particularly during the latter half of the game. Contrary to expectations, the severity of performance impairment did not increase significantly from 51 to 75 h of wakefulness, and caffeine had no significant effects on IGT performance during sleep deprivation. DISCUSSION AND CONCLUSIONS: As a provisional extension of our previous study, these preliminary findings further suggest that the ability to integrate emotion with cognition to guide decision making, a capacity believed to be mediated by the ventromedial prefrontal cortex, may be particularly vulnerable to sleep loss. Moreover, these capacities may not be significantly improved by moderate doses of caffeine, suggesting that they may function separately from simple arousal and alertness systems.

How can apparent decision biases, such as the framing effect, be reduced? Intriguing findings within recent years indicate that foreign language settings reduce framing effects, which has been explained in terms of deeper cognitive processing. Because hard-to-read fonts have been argued to trigger deeper cognitive processing, so-called cognitive disfluency, we tested whether hard-to-read fonts reduce framing effects. We found no reliable evidence for an effect of hard-to-read fonts on four framing scenarios in a laboratory (final N = 158) and an online study (N = 271). However, in a preregistered online study with a rather large sample (N = 732), a hard-to-read font reduced the framing effect in the classic

Risky decision-making under a changing risk level is a complex process involving contextual information. The neural mechanism underlying how sleep deprivation (SD) influences risky decision-making behaviors with a changing risk level has yet to be elucidated. In this study, we used the Balloon Analogue Risk Task (BART) during functional magnetic resonance imaging to investigate the neural correlates of SD-induced changes on decision-making behaviors at different risk levels. Thirty-seven healthy male adults were recruited in this within-subjects, repeat-measure, counterbalanced study. These individuals were examined during a state of rested wakefulness state and after nearly 36 h of total SD. The results showed that SD increased the activation of risk modulation in the left inferior frontal gyrus and were positively correlated with risk-taking propensity after SD. Activation in the ventral striatum and thalamus during cash out was increased, and activation in the middle temporal gyrus after explosion (loss of money) was decreased in sleep-deprived subjects, providing additional evidence for greater risk-taking propensity after SD. These results extend our understanding of the neural mechanism underlying alteration of the risk-taking propensity in sleep-deprived individuals.

This study examined how Internet gaming disorder (IGD) subjects modulating reward and risk at a neural level under a probability-discounting task with functional magnetic resonance imaging (fMRI). Behavioral and imaging data were collected from 19 IGD subjects (22.2 +/- 3.08 years) and 21 healthy controls (HC, 22.8 +/- 3.5 years). Behavior results showed that IGD subjects prefer the probabilistic options to fixed ones and were associated with shorter reaction time, when comparing to HC. The fMRI results revealed that IGD subjects show decreased activation in the inferior frontal gyrus and the precentral gyrus when choosing the probabilistic options than HC. Correlations were also calculated between behavioral performances and brain activities in relevant brain regions. Both of the behavioral performance and fMRI results indicate that people with IGD show impaired risk evaluation, which might be the reason why IGD subjects continue playing online games despite the risks of widely known negative consequence.

People and animals often demonstrate strong attraction or aversion to options with uncertain or risky rewards, yet the neural substrate of subjective risk preferences has rarely been investigated. Here we show that monkeys systematically preferred the risky target in a visual gambling task in which they chose between two targets offering the same mean reward but differing in reward uncertainty. Neuronal activity in posterior cingulate cortex (CGp), a brain area linked to visual orienting and reward processing, increased when monkeys made risky choices and scaled with the degree of risk. CGp activation was better predicted by the subjective salience of a chosen target than by its actual value. These data suggest that CGp signals the subjective preferences that guide visual orienting.

This article offers a new model for bulimia nervosa (BN) that explains both the initial impulsive nature of binge eating and purging, as well as the compulsive quality of the fully developed disorder. The model is based on a review of advances in research on BN and advances in relevant basic psychological science. It integrates transdiagnostic personality risk, eating-disorder-specific risk, reinforcement theory, cognitive neuroscience, and theory drawn from the drug addiction literature. We identify both a state-based and a trait-based risk pathway, and we then propose possible state-by-trait interaction risk processes. The state-based pathway emphasizes depletion of self-control. The trait-based pathway emphasizes transactions between the trait of negative urgency (the tendency to act rashly when distressed) and high-risk psychosocial learning. We then describe a process by which initially impulsive BN behaviors become compulsive over time, and we consider the clinical implications of our model. (PsycINFO Database Record

Functional brain imaging with positron emission tomography and magnetic resonance imaging has been used extensively to map regional changes in brain activity. The signal used by both techniques is based on changes in local circulation and metabolism (brain work). Our understanding of the cell biology of these changes has progressed greatly in the past decade. New insights have emerged on the role of astrocytes in signal transduction as has an appreciation of the unique contribution of aerobic glycolysis to brain energy metabolism. Likewise our understanding of the neurophysiologic processes responsible for imaging signals has progressed from an assumption that spiking activity (output) of neurons is most relevant to one focused on their input. Finally, neuroimaging, with its unique metabolic perspective, has alerted us to the ongoing and costly intrinsic activity within brain systems that most likely represents the largest fraction of the brain's functional activity.

Much of the research on human delay and probability discounting involves the use of hypothetical outcomes, in which participants indicate preferences for outcomes but do not receive them. Research generally shows that hypothetical and potentially real outcomes are discounted at similar rates. One study, however, shows that potentially real cigarettes are discounted more steeply than hypothetical cigarettes in smokers, calling into question the generality of the finding that potentially real and hypothetical money are discounted at similar rates. Using a within-subject design, we tested the extent to which potentially real and hypothetical monetary (Experiment 1) and food-related (Experiment 2) outcomes were discounted at similar rates. We found mixed results for monetary outcomes, in that potentially real outcomes were discounted more steeply than hypothetical outcomes when all participants were included; however, this effect disappeared when only systematic responders were used. In addition, potentially real and hypothetical monetary outcomes were significantly correlated. For food-related outcomes, we found robust and consistent effects that potentially real and hypothetical food outcomes are discounted similarly and that they correlate strongly. Generally, these findings suggest that using hypothetical outcomes generate similar levels of discounting, in particular for food, which is useful for researchers interested in characterizing food-related impulsivity.

8 h (long sleepers) of sleep per night had similar findings, except for the deployment outcome in which those with the shortest sleep were more likely to deploy. CONCLUSIONS: Poor sleep is a detriment to service members' health and readiness. Leadership should redouble efforts to emphasize the importance of healthy sleep among military service members, and future research should focus on the efficacy of interventions to promote healthy sleep and resilience in this population. COMMENTARY: A commentary on this article appears in this issue on page 963.]]>

Insufficient sleep and poor quality sleep are pervasive during adolescence and relate to impairments in cognitive control and increased risk taking. However, the neurobiology underlying the association between sleep and adolescent behavior remains elusive. In the current study, we examine how poor sleep quality relates to cognitive control and reward related brain function during risk taking. Forty-six adolescents participated in a functional magnetic imaging (fMRI) scan during which they completed a cognitive control and risk taking task. Behaviorally, adolescents who reported poorer sleep also exhibited greater risk-taking. This association was paralleled by less recruitment of the dorsolateral prefrontal cortex (DLPFC) during cognitive control, greater insula activation during reward processing, and reduced functional coupling between the DLPFC and affective regions including the insula and ventral striatum during reward processing. Collectively, these results suggest that poor sleep may exaggerate the normative imbalance between affective and cognitive control systems, leading to greater risk-taking in adolescents.

Sleep remains a major mystery of biology. In particular, little is known about the mechanisms that account for the drive to sleep. In an unbiased screen of more than 12,000 Drosophila lines, we identified a single gene, nemuri, that induces sleep. The NEMURI protein is an antimicrobial peptide that can be secreted ectopically to drive prolonged sleep (with resistance to arousal) and to promote survival after infection. Loss of nemuri increased arousability during daily sleep and attenuated the acute increase in sleep induced by sleep deprivation or bacterial infection. Conditions that increase sleep drive induced expression of nemuri in a small number of fly brain neurons and targeted it to the sleep-promoting, dorsal fan-shaped body. We propose that NEMURI is a bona fide sleep homeostasis factor that is particularly important under conditions of high sleep need; because these conditions include sickness, our findings provide a link between sleep and immune function.

The Cognitive Reflection Test (CRT; Frederick, 2005) is designed to measure the tendency to override a prepotent response alternative that is incorrect and to engage in further reflection that leads to the correct response. In this study, we showed that the CRT is a more potent predictor of performance on a wide sample of tasks from the heuristics-and-biases literature than measures of cognitive ability, thinking dispositions, and executive functioning. Although the CRT has a substantial correlation with cognitive ability, a series of regression analyses indicated that the CRT was a unique predictor of performance on heuristics-and-biases tasks. It accounted for substantial additional variance after the other measures of individual differences had been statistically controlled. We conjecture that this is because neither intelligence tests nor measures of executive functioning assess the tendency toward miserly processing in the way that the CRT does. We argue that the CRT is a particularly potent measure of the tendency toward miserly processing because it is a performance measure rather than a self-report measure.

The dorsal and ventral aspects of the prefrontal cortex (PFC) are the two regions most consistently recruited in divergent thinking tasks. Given that frontal tasks have been shown to be vulnerable to sleep loss, we explored the impact of a single night of sleep deprivation on fluency (i.e., number of generated responses) and PFC function during divergent thinking. Participants underwent functional magnetic resonance imaging scanning twice while engaged in the Alternate Uses Task (AUT) - once following a single night of sleep deprivation and once following a night of normal sleep. They also wore wrist activity monitors, which enabled us to quantify daily sleep and model cognitive effectiveness. The intervention was effective, producing greater levels of fatigue and sleepiness. Modeled cognitive effectiveness and fluency were impaired following sleep deprivation, and sleep deprivation was associated with greater activation in the left inferior frontal gyrus (IFG) during AUT. The results suggest that an intervention known to temporarily compromise frontal function can impair fluency, and that this effect is instantiated in the form of an increased hemodynamic response in the left IFG.

STUDY OBJECTIVES: Using a gambling task, we investigated how 24 hours of sleep deprivation modulates the neural response to the making of risky decisions with potentially loss-bearing outcomes. DESIGN: Two experiments involving sleep-deprived subjects were performed. In the first, neural responses to decision making and reward outcome were evaluated. A second control experiment evaluated responses to reward outcome only. PARTICIPANTS: Healthy right-handed adults participated in these experiments (26 [mean age 21.3 years] in Experiment 1 and 13 [mean age 21.7 years] in Experiment 2.) MEASUREMENTS AND RESULTS: Following sleep deprivation, choices involving higher relative risk elicited greater activation in the right nucleus accumbens, signifying an elevated expectation of the higher reward once the riskier choice was made. Concurrently, activation for losses in the insular and orbitofrontal cortices was reduced, denoting a diminished response to losses. This latter finding of reduced insular activation to losses was also true when volunteers were merely shown the results of the computer's decision, that is, without having to make their own choice. CONCLUSIONS: These results suggest that sleep deprivation poses a dual threat to competent decision making by modulating activation in nucleus accumbens and insula, brain regions associated with risky decision making and emotional processing.