Use Your Imagination: College Women's Responses to a Social‐Evaluative Body Image Threat

This study examined psychological and heart rate responses to an imagined social‐evaluative body image threat in women (N = 97). Participants were randomly assigned to picture themselves trying on swimsuits in a store with a group of friends (social‐evaluative threat) or alone (non‐social‐evaluative threat). Measures of state body image and heart rate recordings were completed prior to and following the scenario. A significant group‐by‐time interaction was found for state body image, F(2, 93) = 3.69, p = .03, with the highest body shame and social physique anxiety reported in the social‐evaluative group. No differences were found for heart rate. The findings highlight the usefulness of imagined scenarios when examining psychological responses and the challenges of capturing changes in physiological outcomes.     

Antisaccade performance in schizophrenia patients,their first‐degree biological relatives,and community comparison subjects: Data from the COGS study

The antisaccade task is a widely used technique to measure failure of inhibition, an important cause of cognitive and clinical abnormalities found in schizophrenia. Although antisaccade performance, which reflects the ability to inhibit prepotent responses, is a putative schizophrenia endophenotype, researchers have not consistently reported the expected differences between first‐degree relatives and comparison groups. Schizophrenia participants (n=219) from the large Consortium on the Genetics of Schizophrenia (COGS) sample (n=1078) demonstrated significant deficits on an overlap version of the antisaccade task compared to their first‐degree relatives (n=443) and community comparison subjects (CCS; n=416). Although mean antisaccade performance of first‐degree relatives was intermediate between schizophrenia participants and CCS, a linear mixed‐effects model adjusting for group, site, age, and gender found no significant performance differences between the first‐degree relatives and CCS. However, admixture analyses showed that two components best explained the distributions in all three groups, suggesting two distinct doses of an etiological factor. Given the significant heritability of antisaccade performance, the effects of a genetic polymorphism is one possible explanation of our results.     

Future‐directed thinking and depression in relapsing‐remitting multiple sclerosis

Background. Research has shown that depression is associated with a view of the future characterized by reduced anticipation of future positive experiences, but not necessarily increased anticipation of future negative experiences. The aim of the present study was to investigate how participants with relapsing‐remitting multiple sclerosis (MS) anticipated their future in terms of positive and negative events. Design. A mixed design compared three groups of participants on a measure of future thinking using an adapted verbal fluency paradigm. Methods. Depressed MS participants (N = 14), non‐depressed MS participants (N = 28) and healthy control participants (N = 26) were assessed on their ability to generate future positive and negative experiences. A content analysis was also conducted on the responses generated by the MS depressed and MS non‐depressed groups according to whether or not they were related to MS. Results. The MS depressed group anticipated significantly fewer future positive events than the healthy control group and the MS non‐depressed group. The three groups did not differ in the total numbers of anticipated future negative events, though the MS depressed group did anticipate a significantly higher proportion of MS‐related negative events. Conclusions. Like depressed but physically healthy individuals, the MS depressed group was characterized by a lack of positive thoughts about the future, rather than an increased number of negative thoughts. The clinical implications of these findings are discussed along with recommendations for future research.     

Investigating the Relationship Between FMR1 Allele Length and Cognitive Ability in Children: A Subtle Effect of the Normal Allele Range on the Normal Ability Range?

The FMR1 gene contains a trinucleotide repeat tract which can expand from a normal size of around 30 repeats to over 200 repeats, causing mental retardation (Fragile X Syndrome). Evidence suggests that premutation males (55‐200 repeats) are susceptible to a late‐onset tremor/ataxia syndrome and females to premature ovarian failure, and that intermediate alleles (～41‐55 repeats) and premutations may be in excess in samples with special educational needs. We explored the relationship between FMR1 allele length and cognitive ability in 621 low ability and control children assessed at 4 and 7 years, as well as 122 students with high IQ. The low and high ability and control samples showed no between‐group differences in incidence of longer alleles. In males there was a significant negative correlation between allele length and non‐verbal ability at 4 years (p = 0.048) , academic achievement in maths (p = 0.003) and English (p = 0.011) at 7 years, and IQ in the high ability group (p = 0.018) . There was a significant negative correlation between allele length and a standardised score for IQ and general cognitive ability at age 7 in the entire male sample (p = 0.002) . This suggests that, within the normal spectrum of allele length, increased repeat numbers may have a limiting influence on cognitive performance.     

Higher expression of EpCAM is associated with poor clinical and pathological responses in breast cancer patients undergoing neoadjuvant chemotherapy

Neoadjuvant chemotherapy (NAC) is a standard regimen in treatment of breast cancer patients, but some are resistant to NAC. We hypothesized that breast cancer cells overexpressing epithelial cell adhesion molecule (EpCAM) could be resistant to NAC, contributing to a poor prognosis. Seventy patients with breast cancer were treated with NAC. Core needle biopsy (CNB) specimens and resected tumors before and after NAC, respectively, were examined for expression of EpCAM. In resected tumors, high EpCAM expression correlated with lymphovascular invasion status and nuclear grade (P = 0.01 and 0.008, respectively), and was associated with poor pathological and clinical responses (P < 0.001). High tumoral EpCAM expression in resected tumor was independently related to a poor pathological response. Patients with high EpCAM expression before and after NAC (high‐to‐high group) showed worse pathological and clinical responses (P = 0.008 and <0.001, respectively) than the patients with high and low EpCAM expression before and after NAC, respectively (high‐to‐low group). The overall survival rate of the high‐to‐high group appeared shorter compared with the high‐to low‐group (P = 0.049). Our findings imply that higher levels of EpCAM in breast cancer may be associated with poor response to NAC via a potential chemoresistant effect.     

Sleep‐disordered breathing in children is associated with impairment of sleep stage‐specific shift of cardiac autonomic modulation

We examined the effects of sleep stages and sleep‐disordered breathing (SDB) on autonomic modulation in 700 children. Apnea hypopnea index (AHI) during one 9 h night‐time polysomnography was used to define SDB. Sleep stage‐specific autonomic modulation was measured by heart rate variability (HRV) analysis of the first available 5 min RR intervals from each sleep stage. The mean [standard deviation (SD)] age was 112 (21) months (49% male and 25% non‐Caucasian). The average AHI was 0.79 (SD = 1.03) h^?1, while 73.0%, 25.8% and 1.2% of children had AHI <1 (no SDB), 1–5 (mild SDB) and ≥5 (moderate SDB), respectively. In the no SDB group, the high frequency (HF) and root mean square SD (RMSSD) increased significantly from wake to Stage 2 and slow wave sleep (SWS), and then decreased dramatically when shifting into rapid eye movement (REM) sleep. In the moderate SDB group, the pattern of HRV shift was similar to that of no SDB. However, the decreases in HF and RMSSD from SWS to REM were more pronounced in moderate SDB children [between‐group differences in HF (?24% in moderate SDB versus ?10% in no SDB) and RMSSD (?27% versus ?12%) were significant (P < 0.05)]. The REM stage HF is significantly lower in the moderate SDB group compared to the no SDB group [mean (standard error): 4.49 (0.43) versus 5.80 (0.05) ms², respectively, P < 0.05]. Conclusions are that autonomic modulation shifts significantly towards higher parasympathetic modulation from wake to non‐rapid eye movement sleep, and reverses to a less parasympathetic modulation during REM sleep. However, the autonomic modulation is impaired among children with moderate SDB in the directions of more reduction in parasympathetic modulation from SWS to REM sleep and significantly weaker parasympathetic modulation in REM sleep, which may lead to higher arrhythmia vulnerability, especially during REM sleep.     

Stress vulnerability and the effects of moderate daily stress on sleep polysomnography and subjective sleepiness

The purpose of this study was to investigate if and how sleep physiology is affected by naturally occurring high work stress and identify individual differences in the response of sleep to stress. Probable upcoming stress levels were estimated through weekly web questionnaire ratings. Based on the modified FIRST‐scale (Ford insomnia response to stress) participants were grouped into high (n = 9) or low (n = 19) sensitivity to stress related sleep disturbances (Drake et al., 2004). Sleep was recorded in 28 teachers with polysomnography, sleep diaries and actigraphs during one high stress and one low stress condition in the participants home. EEG showed a decrease in sleep efficiency during the high stress condition. Significant interactions between group and condition were seen for REM sleep, arousals and stage transitions. The sensitive group had an increase in arousals and stage transitions during the high stress condition and a decrease in REM, whereas the opposite was seen in the resilient group. Diary ratings during the high stress condition showed higher bedtime stress and lower ratings on the awakening index (insufficient sleep and difficulties awakening). Ratings also showed lower cognitive function and preoccupation with work thoughts in the evening. KSS ratings of sleepiness increased during stress for the sensitive group. Saliva samples of cortisol showed no effect of stress. It was concluded that moderate daily stress is associated with a moderate negative effect on sleep sleep efficiency and fragmentation. A slightly stronger effect was seen in the sensitive group.     

The impact of physical proximity and attachment working models on cardiovascular reactivity: Comparing mental activation and romantic partner presence

Close relationships, especially high‐quality romantic relationships, are consistently associated with positive physical health outcomes. Attenuated cardiovascular reactivity is one physiological mechanism implicated in explaining these effects. Drawing on attachment and social baseline theories, this experimental study evaluated two potential affiliative cues as mechanisms through which romantic relationships may attenuate cardiovascular reactivity to a laboratory‐based stressor. Prior to a cold pressor task, 102 participants were randomly assigned to either have their partner physically present, call upon a mental representation of their partner, or think about their day during the stressor. Consistent with our preregistered hypotheses, participants in both the partner present and mental activation conditions had significantly lower blood pressure (BP) reactivity during the cold pressor task compared to control participants for both systolic (d = ?0.54) and diastolic BP (d = ?0.53), but no significant differences emerged for heart rate or heart rate variability. Although participants in the partner present and mental activation conditions had similar BP reactivity to the cold pressor task, those in the partner present condition reported significantly less pain as a result of the task. The difference in BP reactivity by condition was moderated—BP reactivity was greater for people with lower self‐reported relationship satisfaction. The results suggest that accessing the mental representation of a romantic partner and a partner’s presence each buffer against exaggerated acute stress responses to a similar degree.     

Testing food‐related inhibitory control to high‐ and low‐calorie food stimuli: Electrophysiological responses to high‐calorie food stimuli predict calorie and carbohydrate intake

Maintaining a healthy diet has important implications for physical and mental health. One factor that may influence diet and food consumption is inhibitory control—the ability to withhold a dominant response in order to correctly respond to environmental demands. We examined how N2 amplitude, an ERP that reflects inhibitory control processes, differed toward high‐ and low‐calorie food stimuli and related to food intake. A total of 159 participants (81 female; M age = 23.5 years; SD = 7.6) completed two food‐based go/no‐go tasks (one with high‐calorie and one with low‐calorie food pictures as no‐go stimuli) while N2 amplitude was recorded. Participants recorded food intake using the Automated Self‐Administered 24‐hour Dietary Recall system. Inhibiting responses toward high‐calorie stimuli elicited a larger (i.e., more negative) no‐go N2 amplitude; inhibiting responses toward low‐calorie stimuli elicited a smaller no‐go N2 amplitude. Participants were more accurate during the high‐calorie than low‐calorie task, but took longer to respond on go trials toward high‐calorie rather than low‐calorie stimuli. When controlling for age, gender, and BMI, larger high‐calorie N2 difference amplitude predicted lower caloric intake (β = 0.17); low‐calorie N2 difference amplitude was not related to caloric intake (β = −0.03). Exploratory analyses revealed larger high‐calorie N2 difference amplitude predicted carbohydrate intake (β = 0.22), but not protein (β = 0.08) or fat (β = 0.11) intake. Results suggest that withholding responses from high‐calorie foods requires increased recruitment of inhibitory control processes, which may be necessary to regulate food consumption, particularly for foods high in calories and carbohydrates.     

Frontal EEG asymmetry as predictor of physiological responses to aversive memories

Evidence suggests that asymmetry in frontal electrical activity predicts responses to aversive experiences, such that higher left‐sided activity might dampen responses to trauma reminders. We measured frontal asymmetry at rest and during viewing of a trauma film, and assessed startle responses to film‐reminder images. To explore potential moderators, we compared two films (Study 1; N = 64) and modulated reappraisal (Study 2; N = 72). As expected, left frontal activation during film viewing predicted dampened responses in individuals who viewed a staged road accident. However, this effect tended to be reversed when a genocide documentary was used. In Study 2, all participants viewed the genocide film. Left frontal activity at rest again predicted higher startle responses, while reappraisal did not moderate the effects. Thus, the type of trauma film plays a crucial role in the effects of frontal asymmetry, which warrants further critical investigation.     

Decreased reaction time variability is associated with greater cardiovascular responses to acute stress

Cardiovascular (CV) responses to mental stress are prospectively associated with poor CV outcomes. The association between CV responses to mental stress and reaction times (RTs) in aging individuals may be important but warrants further investigation. The present study assessed RTs to examine associations with CV responses to mental stress in healthy, older individuals using robust regression techniques. Participants were 262 men and women (mean age = 63.3 ± 5.5 years) from the Whitehall II cohort who completed a RT task (Stroop) and underwent acute mental stress (mirror tracing) to elicit CV responses. Blood pressure, heart rate, and heart rate variability were measured at baseline, during acute stress, and through a 75‐min recovery. RT measures were generated from an ex‐Gaussian distribution that yielded three predictors: mu‐RT, sigma‐RT, and tau‐RT, the mean, standard deviation, and mean of the exponential component of the normal distribution, respectively. Decreased intraindividual RT variability was marginally associated with greater systolic (B = ?.009, SE = .005, p = .09) and diastolic (B = ?.004, SE = .002, p = .08) blood pressure reactivity. Decreased intraindividual RT variability was associated with impaired systolic blood pressure recovery (B = ?.007, SE = .003, p = .03) and impaired vagal tone (B = ?.0047, SE = .0024, p = .045). Study findings offer tentative support for an association between RTs and CV responses. Despite small effect sizes and associations not consistent across predictors, these data may point to a link between intrinsic neuronal plasticity and CV responses.     

Sustaining self‐regulatory efficacy and psychological outcome expectations for postnatal exercise: Effects of a group‐mediated cognitive behavioural intervention

Objective . The objective of the current investigation was to examine if the effects of a group‐mediated cognitive behavioural counselling plus exercise intervention were superior to the effects of a standard exercise care condition on postnatal mothers' self‐regulatory efficacy (SRE), outcome expectations (OEs) and self‐directed physical activity (PA). Design . The design of the study consisted of two intervention conditions; group‐mediated cognitive behavioural counselling plus exercise (GMCB) and standard exercise (SE). Each condition consisted of two phases; a 4‐week supervised, centre‐based intensive exercise training phase followed by a 4‐week home‐based phase. Methods . Participants were 57 postnatal women randomly assigned to conditions (SE: N = 31; GMCB: N = 26). Measures of SRE and OEs were assessed prior to and following the centre‐based aspect of the intervention. Physical activity was measured following the intensive exercise training phase as well as the home‐based phase. Results . GMCB participants' SRE and OEs were sustained during the intervention whereas those of SE participants declined. GMCB participants also reported significantly greater time spent engaging in self‐directed PA at the conclusion of the intensive and home‐based phases. Mediation analysis revealed that SRE partially mediated the relationship between intervention condition and post home‐based PA as confirmed by a significant sobel test. Conclusions . These findings suggest that a theory‐based GMCB counselling plus exercise intervention is superior to the SE condition in sustaining SRE and OEs, and in promoting greater self‐directed PA. SRE partially mediated the relationship between intervention condition and post home‐based PA supporting the targeting of that variable for change as part of the intervention.     

Physiological adaptation to recurrent social stress of extraversion

The present studies examined the influence of extraversion on physiological reactivity, recovery, and physiological habituation‐sensitization to repeated social stressors. In Study 1, subjective and physiological data were collected from 97 college students who were categorized as high (n = 51) and low (n = 46) on extraversion (NEO‐FFI) across five laboratory stages: baseline, stress 1, poststress 1, stress 2, and poststress 2. Results indicated high extraversion (HE) participants exhibited relative lesser heart rate (HR) reactivity and respiratory sinus arrhythmia (RSA) withdrawals to, and more complete HR and RSA recovery after the first social stress, and also exhibited relative lesser HR reactivity to the second social stress. When repeatedly exposed to a social stressor, HE participants showed pronounced systolic blood pressure (SBP) adaptation, low extraversion (LE) participants displayed diastolic blood pressure (DBP) sensitization. In Study 2, data were collected from another 78 participants (HE: n = 40, LE: n = 38) across the same laboratory stages with speech performance videotaped. After controlling for the speech styles, Study 2 found the same HR response and SBP/DBP adaptation pattern across extraversion groups to social stress as Study 1 but not RSA reactivity. These findings suggest extraverts exhibit more adaptive physiological reactivity to recurrent social stressors, which thus might benefit their health.     

Blood pressure responses and incentive appraisals as a function of perceived ability and objective task demand

This experiment examined the role perceptions of ability may play in determining the impact of task demand on cardiovascular responses indicative of active coping. Subjects first performed a scanning task and received feedback indicating that they had either low or high scanning ability. They then were presented with the opportunity to earn one of two incentives by attaining either an objectively low or objectively high standard of performance on a second scanning task. Immediately prior to and during the 1-min performance period, systolic and diastolic blood pressure responses were greater in the difficult standard condition than in the easy standard condition for those who received high-ability feedback but were somewhat diminished in the difficult standard condition as compared with the easy standard condition for those who received low-ability feedback. Whereas high-ability subjects tended to have less pronounced pressor responses than did low-ability subjects when the second task was objectively easy, they had more pronounced pressor responses than low-ability subjects when the second task was objectively difficult. Analysis of goal attractiveness ratings obtained just prior to task performance showed a general correspondence between subjects' anticipatory blood pressure responses and their appraisals of the incentives. Implications for several lines of investigation are discussed.     

Age‐Related Difference in Postural Control During Recovery from Posterior and Anterior Perturbations

Decreased reactive postural responses in elderly adults may place them at increased risk for falls and related injuries. The first step in addressing the high rate of falls in the elderly population is to determine a baseline for postural response in healthy young and healthy elderly individuals. To determine these age‐related differences in reactive postural responses during recovery from posterior and anterior perturbations, we used the tether‐release method in conjunction with a motion analysis system to evaluate overall movement latencies, overall movement amplitude and velocity, and joint‐specific amplitude and velocity in healthy young (n = 10, mean age=25 ± 5) and healthy elderly participants (n = 10, mean age = 67 ± 6). During posterior perturbations, healthy elderly participants had increased recovery time (P = 0.01) and ratio of center of mass to step length (P = 0.013) when compared with young participants. Elderly participants also had decreased step length (P = 0.006), peak COM velocity (P = 0.01), peak knee flexion angle (P = 0.002), and decreased hip (P = 0.005) and knee (P = 0.0005) average angular velocity when compared with young participants. We conclude that these movement deficiencies at the hip and knee limited the length of the recovery step. With this restricted step, elderly participants could not achieve adequate mechanical advantage to counteract the displacement of their COM using a single step. During anterior perturbations, elderly participants did not exhibit any significant differences compared to young participants in overall movement variables. This understanding of postural responses in healthy individuals is clinically relevant to the development of rehabilitation programs for individuals at high fall risk. Anat Rec, 298:346–353, 2015. © 2014 Wiley Periodicals, Inc.     

Biofilm formation of beta‐hemolytic group G Streptococcus dysgalactiae subspecies equisimilis isolates and its association with emm polymorphism

Biofilm formation has been well known as a determinant of bacterial virulence. Group G Streptococcus dysgalactiae subspecies equisimilis (SDSE), a relevant pathogen with increasing medical importance, was evaluated for the biofilm‐forming potential. Microtiter plate assay was used to assess the most feasible medium for group G SDSE to form a biofilm. Among 246 SDSE isolates examined, 46.7%, 43.5%, 33.3%, and 26.4% of isolates showed moderate or strong biofilm‐forming abilities using tryptic soy broth (TSB), brain heart infusion broth (BHI), Todd‐Hewitt broth (THB), and C medium with 30 mM glucose (CMG), respectively. The addition of glucose significantly increased the biofilm‐forming ability of group G SDSE. FCT (fibronectin–collagen–T‐antigen) typing of SDSE was first undertaken and 11 FCT types were found. Positive associations of stG10.0 or negative associations of stG245.0, stG840.0, and stG6.1 with biofilm‐forming ability of SDSE were, respectively, found. This was the first investigation demonstrating biofilm‐forming potential in clinical group G SDSE isolates; also, some significant associations of biofilm‐forming ability with certain emm types were presented.     

Effects of continuous and intermittent exercise on executive function in children aged 8–10 years

Understanding the effects of acute exercise on executive function in prepubescent children may be important for the enhancement of school performance. This study assessed the effect of an acute bout of continuous (CONT) or intermittent (INT), moderate‐intensity treadmill exercise on executive function in young children. Twenty healthy children, mean (SD); age: 8.8 (0.8) years; height: 140 (9) cm; weight: 36 (11) kg; boys: n = 9, performed a graded‐exercise test to determine maximal oxygen uptake, and two 15‐min submaximal bouts of treadmill exercise; protocols were either CONT or INT. During CONT, participants ran at 90% of gas exchange threshold. During INT, participants performed six consecutive 2.5 min blocks of exercise, which were designed to reflect children's typical activity patterns, comprising 45 s at a heavy intensity, 33 s at a moderate intensity, 10 s at a severe intensity, and 62 s at a low intensity. Participants performed the Stroop task before the submaximal exercise bouts and after, at 1‐, 15‐, and 30‐min intervals. Near‐infrared spectroscopy (NIRS) measured cerebral perfusion and oxygenation. Regardless of condition, Stroop performance was improved at 1 min after compared to before, 54.9 (9.8) s versus 57.9 (11) s, respectively, p < .01, and improvements were maintained until 30 min after. NIRS (oxyhemoglobin, total hemoglobin) explained a significant amount of variance in the change in Stroop performance for INT only (49%, p < .05). An acute bout of exercise, of either an intermittent or continuous nature, improves executive function in children, and effects are maintained for ≤ 30 min following exercise cessation. Accordingly, it is recommended that children should engage in physical activity during periods of school recess.     

The effects of Mycobacteria vaccae derivative on allergen-specific responses in children with atopic dermatitis

The capacity of microbial products to inhibit allergic inflammation make them logical candidates for novel therapies in allergic diseases such as atopic dermatitis. To assess the effects of intradermal Mycobacterium vaccae derivative on allergen‐specific immune responses in children with moderate to severe atopic dermatitis. Peripheral blood mononuclear cells were isolated from children aged 5–16 years who received intradermal injections of M. vaccae derivative AVAC^TM (n = 26) or placebo (n = 34) three times at 2‐weekly intervals, weeks 0, 2 and 4. Cytokine [interleukin (IL)‐13, interferon (IFN)‐γ and IL‐10] responses to allergen [house dust mite (HDM)], mitogen [phytohaemagglutinin (PHA)], Staphylococcal enterotoxin B (SEB) and Toll‐like receptor (TLR) ligands were assessed. At week 8 (1 month after all injections given) children in the AVAC group showed a significant increase in IL‐10 (P = 0·009), T helper type 1 (Th1) IFN‐γ (P = 0·017) and Th2 IL‐13 (P = 0·004) responses to HDM compared with baseline (week 0). There were no significant changes in any cytokine production in the placebo. HDM‐specific IL‐10 responses remained significantly higher (P = 0·014) than at baseline in the AVAC group by week 12; however, the HDM‐specific IL‐13 and IFN‐γ responses were no longer significantly different from baseline. IL‐13 (r = 0·46, P < 0·001) and IL‐10 (r = 0·27, P = 0·044) responses to HDM were correlated with total immunoglobulin E but not with disease severity. There were no effects of AVAC on mitogen, SEB, TLR‐2‐ or TLR‐4‐mediated responses. This M. vaccae derivative appeared to modulate responses to HDM selectively, suggesting the capacity for in vivo effects on allergen‐specific immune responses.     

Sleep-dependent modulation of affectively guided decision-making

A question of great interest in current sleep research is whether and how sleep might facilitate complex cognitive skills such as decision‐making. The Iowa Gambling Task (IGT) was used to investigate effects of sleep on affect‐guided decision‐making. After a brief standardized preview of the IGT that was insufficient to learn its underlying rule, participants underwent a 12‐h delay containing either a normal night’s sleep (Sleep group; N = 28) or continuous daytime wake (Wake group; N = 26). Following the delay, both groups performed the full IGT. To control for circadian effects, two additional groups performed both the preview and the full task either in the morning (N = 17) or the evening (N = 21). In the IGT, four decks of cards were presented. Draws from two ‘advantageous decks’ yielded low play‐money rewards, occasional low losses and, over multiple draws, a net gain. Draws from ‘disadvantageous’ decks yielded high rewards, occasional high losses and, over multiple draws, a net loss. Participants were instructed to win and avoid losing as much as possible, and better performance was defined as more advantageous draws. Relative to the wake group, the sleep group showed both superior behavioral outcome (more advantageous draws) and superior rule understanding (blindly judged from statements written at task completion). Neither measure differentiated the two control groups. These results illustrate a role of sleep in optimizing decision‐making, a benefit that may be brought about by changes in underlying emotional or cognitive processes.     

Self‐regulatory ability,fatigue, and the experience of pain: Mechanistic insights from pain‐free undergraduates

Self‐regulatory (SR) ability is an important resource for managing pain, but chronic pain patients experience chronic self‐regulatory fatigue even when they are not in pain. Pressure pain thresholds (PPT) and pain inhibition are two mechanisms that differentiate people with and without chronic pain. It was hypothesized that trait SR ability would be associated with higher PPT and better pain inhibition and that PPT and pain inhibition would be lower following high versus low SR fatigue. Three studies tested these hypotheses. Study 1 had 240 pain‐free undergraduates complete measures of trait SR ability and PPT; 122 also provided data on pain inhibition. Study 2 had 38 of Study 1’s participants return for two additional sessions in which they underwent PPT testing under conditions of high or low SR fatigue (within‐person, counterbalanced). Study 3 repeated these procedures with pain inhibition as the outcome (n = 39). Results revealed that individual differences in SR ability were not associated with PPT or pain inhibition (all ps > 0.05). Within people, neither PPT (F(1, 36) = 1.57, p = 0.22) nor pain inhibition (F(1, 37) = 1.79, p = 0.19) were significantly different under conditions of low versus high SR fatigue. Results do not support the hypotheses that PPT or pain inhibition associate with individual differences in trait SR ability or transient changes in state SR fatigue in the absence of pain. Instead, the SR deficits in chronic pain patients may arise from the experience of chronic pain.