The effects of acute stress on core executive functions: A meta-analysis and comparison with cortisol

Autonomic Stress Response and Perceived Effort Jointly Inform on Dual Tasking in Aging

The study investigated, through neuroendocrinological, subjective and behavioral assessments, how aging individuals cope with locomotor-cognitive dual-tasking and whether physical activity habits influence the acute response to locomotor-cognitive performance. Seventy-nine healthy participants aged 55–85 years were assessed on locomotor (gait speed, stride length) and cognitive (working memory) performances under single- and dual-task (ST, DT) conditions, and habitual physical activity (daily steps). Rating of perceived exertion (RPE) was assessed immediately after performance. Salivary α-amylase (sAA) was measured prior, immediately and 5 min after performance. Gait and working memory variables, the area under the curve of sAA (AUC) and DT–ST differences (DT effects) were computed. AUC was higher when the ST or DT performance involved a locomotor component and showed a pre-to-post increment after DT only, whereas RPE was higher when performance involved a cognitive component. Daily steps neither predicted sAA, nor RPE. Associations between DT effects on sAA, RPE and performance emerged in high-active participants only. In aging individuals, DT walking elicits an autonomic stress response presumably led by the challenge to share resources relying upon common neural substrates. This autonomic response seems tuned to gait performance and subjective evaluation of effort in those more accustomed to walking.

Mild acute stress improves response speed without impairing accuracy or interference control in two selective attention tasks: Implications for theories of stress and cognition

Acute stress is generally thought to impair performance on tasks thought to rely on selective attention. This effect has been well established for moderate to severe stressors, but no study has examined how a mild stressor-the most common type of stressor-influences selective attention. In addition, no study to date has examined how stress influences the component processes involved in overall selective attention task performance, such as controlled attention, automatic attentional activation, decision-making, and motor abilities. To address these issues, we randomly assigned 107 participants to a mild acute stress or control condition. As expected, the mild acute stress condition showed a small but significant increase in cortisol relative to the control condition. Following the stressor, we assessed attention with two separate flanker tasks. One of these tasks was optimized to investigate component attentional processes using computational cognitive modeling, whereas the other task employed mouse-tracking to illustrate how response conflict unfolded over time. The results for both tasks showed that mild acute stress decreased response time (i.e., increased response speed) without influencing accuracy or interference control. Further, computational modeling and mouse-tracking analyses indicated that these effects were due to faster motor action execution time for chosen actions. Intriguingly, however, cortisol responses were unrelated to any of the observed effects of mild stress. These results have implications for theories of stress and cognition, and highlight the importance of considering motor processes in understanding the effects of stress on cognitive task performance.

Striatal responsiveness to reward under threat-of-shock and working memory load: A preliminary study

INTRODUCTION

Reward and stress are important determinants of motivated behaviors. Striatal regions play a crucial role in both motivation and hedonic processes. So far, little is known on how cognitive effort interacts with stress to modulate reward processes. This study examines how cognitive effort (load) interacts with an unpredictable acute stressor (threat-of-shock) to modulate motivational and hedonic processes in healthy adults.

MATERIALS AND METHODS

A reward task, involving stress with unpredictable mild electric shocks, was conducted in 23 healthy adults aged 20-37 (mean age: 24.7 ± 0.9; 14 females) during functional magnetic resonance imaging (fMRI). Manipulation included the use of (a) monetary reward for reinforcement, (b) threat-of-shock as the stressor, and (c) a spatial working memory task with two levels of difficulty (low and high load) for cognitive load. Reward-related activation was investigated in a priori three regions of interest, the nucleus accumbens (NAcc), caudate nucleus, and putamen.

RESULTS

During anticipation, threat-of-shock or cognitive load did not affect striatal responsiveness to reward. Anticipated reward increased activation in the ventral and dorsal striatum. During feedback delivery, both threat-of-shock and cognitive effort modulated striatal activation. Higher working memory load blunted NAcc responsiveness to reward delivery, while stress strengthened caudate nucleus reactivity regardless reinforcement or load.

CONCLUSIONS

These findings provide initial evidence that both stress and cognitive load modulate striatal responsiveness during feedback delivery but not during anticipation in healthy adults. Of clinical importance, sustained stress exposure might go along with dysregulated arousal, increasing therefore the risk for the development of maladaptive incentive-triggered motivation. This study brings new insight that might help to build a framework to understand common stress-related disorders, given that these psychiatric disorders involve disturbances of the reward system, cognitive deficits, and abnormal stress reactivity.

The effects of negative air ions on cognitive function: an event-related potential (ERP) study

This study investigated the effects of negative air ions (NAIs) on cognitive function in young male adults, specifically examined whether NAIs could influence the behavioral and neuroelectrical indices of inhibition. Thirty-nine young adults participated in the NAI and the control sessions in a counterbalanced order. A computerized Stroop color-word test was administrated, and N2 of the event-related potential was recorded and then analyzed. The results revealed that participants in the NAI session demonstrated shorter reaction times and higher accuracy for both Stroop congruent and incongruent trials. Larger N2 amplitudes were also observed in the NAI session than in the control session, whereas no alterations in the latencies were found. These findings suggest that NAIs resulted in a general improvement in both basic information processing and inhibition. This facilitation may be related to an enhanced neuronal processing or alertness status reflected by larger amplitudes of the N2 component.

Insomnia-related Memory Impairment in Individuals With Very Complex Chronic Pain

OBJECTIVE

To investigate the specific effect of insomnia on neuropsychological functioning in patients with very complex chronic pain.

BACKGROUND

Individuals with insomnia disorder or chronic pain often experience cognitive deficits, with both conditions appearing to correlate with impairments in neuropsychological functions. As insomnia often occurs comorbid with chronic pain, distinguishing the differential effects of these two syndromes on an individual's neuropsychological functioning can be challenging. Comorbid depressive symptoms in these individuals, which may also affect cognitive function, may further obscure the associations between chronic pain, insomnia, and the neuropsychological profile.

METHODS

The neuropsychological function of 22 individuals with very complex chronic pain was assessed using specialized tests examining aspects of memory and executive functioning. The severity of insomnia, depression, and anxiety was measured using questionnaires, and pain levels were assessed using a visual analog scale. Pain medications were transformed to the morphine-equivalent daily dose.

RESULTS

Insomnia severity was found to predict memory function, accounting for 32.4% of the variance: A 1 SD increase in insomnia severity decreased memory function by 0.57 SD. The negative correlation between insomnia and memory was significant even after controlling for pain level, morphine-equivalent daily dose, and comorbid levels of anxiety and depression.

CONCLUSIONS

Insomnia severity independently predicted memory function in patients with very complex chronic pain, even after controlling for other factors known to impair cognitive function. Insomnia may possibly explain some of the cognitive impairments related to chronic pain; thus, screening for, and treating, sleep disturbances may be a central aspect of chronic pain rehabilitation.

Impulsivity in the self-harm and suicidal behavior of young people: A systematic review and meta-analysis

BACKGROUND

Impulsivity is considered a possible phenotype underlying the expression of self-harm and suicidal behaviors. Yet impulsivity is a not a unitary construct and there is evidence that different facets of impulsivity follow different neurodevelopmental trajectories and that some facets may be more strongly associated with such behaviors than others. Moreover, it is unclear whether impulsivity is a useful predictor of self-harm or suicidal behavior in young people, a population already considered to display heightened impulsive behavior.

METHODS

A systematic review and meta-analysis of studies published in Medline, PubMed, PsychInfo or Embase between 1970 and 2017 that used a neurocognitive measure to assess the independent variable of impulsivity and the dependent variable of self-harm and/or suicidal behavior among young people (mean age < 30 years old).

RESULTS

6183 titles were identified, 141 full texts were reviewed, and 18 studies were included, with 902 young people with a self-harm or suicidal behavior and 1591 controls without a history of these behaviors. Deficits in inhibitory control (13 studies, SMD 0.21, p-value = 0.002, 95% confidence interval (CI) (0.08-0.34), prediction interval (PI) = 0.06-0.35) and impulsive decision-making (14 studies, SMD 0.17, p-value = 0.008, 95% CI (0.045-0.3), PI = 0.03-0.31) were associated with self-harm or suicidal behavior. There were no significant differences between measures of different facets of impulsivity (ie. delay discounting, risky decision-making, cognitive or response inhibition) and self-harm or suicidal behavior.

CONCLUSION

Multiple facets of impulsivity are associated with suicidal behavior in young people. Future suicide research should be designed to capture impulsive states and investigate the impact on different subtypes of impulsivity.

Physical activity interventions can improve emotion regulation and dimensions of empathy in persons with multiple sclerosis: An exploratory study

BACKGROUND

Persons with multiple sclerosis (PwMS) report difficulties with emotion regulation and empathy. Regular physical activity (RPA) improves dimensions of psychological well-being in PwMS, but it remains unclear if regular physical activity has effects on emotion regulation and empathy. The present study investigated the effect of regular physical activity on emotion regulation and empathy, and explored, if endurance training or coordinative training are better than an active control condition.

METHODS

92 female PwMS (mean age: 37.4 years; age range: 20-57 years; mean EDSS: 2.43) took part in this study. Participants were randomly assigned into endurance training, coordinative training, or active control conditions that all lasted 8 weeks and were yoked on frequency, duration, and social contact. Participants completed questionnaires on emotion regulation, empathy, depression and fatigue before and after the 8-week conditions.

RESULTS

Regulation and control of emotions and empathy improved over time, but more so in the exercising groups, compared to the active control group. No changes over time and between groups were observed for perception and acknowledgement of emotions, emotional expressivity, and empathy, as measured with Reading in the Eyes test. These changes were not influenced by control for depression and fatigue as covariates.

CONCLUSIONS

Both endurance and coordinative exercise training had favorable effects on some aspects of emotion regulation and social cognition such as empathy in PwMS. Such initial results support for examination of exercise training for the treatment of issues of emotion regulation and social interactions in PwMS.

Acute Stress Shapes Creative Cognition in Trait Anxiety

This study examined the cognitive mechanism underlying acute stress in creative cognition among individuals with high and low trait anxiety. Specifically, cognitive inhibition was assessed using the flanker task during acute stress. Fifty-two participants (26 with high trait anxiety, 26 with low trait anxiety, with a mean age of 18.94 years) underwent stress induction via the Trier Social Stress Test (TSST). They all completed the Alternative Uses Test (AUT) and the Remote Associates Test (RAT) before and after the TSST. Biochemical markers (salivary cortisol and salivary alpha amylase) were recorded at regular intervals. The results showed that cognitive inhibition was influenced by trait anxiety and acute stress. In low-trait anxious individuals after experiencing acute stress, there was a lack of cognitive inhibition and they performed better in AUT (fluency), compared to before experiencing acute stress, whereas high-trait anxious individuals showed a decreased interference effect and reduced performance in AUT (fluency, flexibility, and originality). In the RAT, there were shorter response times and increased accuracy after acute stress in both high- and low-trait anxiety groups. Thus, we suggest that cognitive control, which modulates changes in acute stress, influences creative cognition. These findings provide evidence that inhibition control mediates the effect of stress on the creativity of individuals with different trait anxiety.

Acute psychosocial stress and working memory performance: the potential of physical activity to modulate cognitive functions in children

Background

Research suggests that physical activity (PA) enhances cognitive performance and prevents stress-related impairments of higher order cognitive functions like working memory (WM) performance. The aim of the current study was to investigate the effect of PA on WM performance after acute stress exposure in preadolescent children.

Methods

Regular PA was assessed for seven consecutive days during a typical school week using accelerometers in a sample of 44 preadolescent children (14 girls, M_age = 11.29 years, SD_age = 0.67). Following this period, participants performed an automated operational span (OSPAN) task immediately after being exposed to the Trier Social Stress Test for Children (TSST-C).

Results

Children exhibited prototypical response slopes in salivary cortisol and salivary α-amylase as markers of the endocrine and autonomic stress response immediately after psychosocial stress induction. A subsequent two-way ANOVA comparing high- and low-stress responders revealed a significant interaction between group affiliation and PA level on WM performance for both stress markers. Interestingly, best WM performance was demonstrated in children showing both high PA levels and high cortisol (or low α-amylase, respectively) stress responses.

Conclusions

Though patterns differed for salivary cortisol and salivary α-amylase, overall findings suggest that PA buffers the negative effects of stress on cognitive performance in children.

Advanced cancer patients' understanding of prognostic information: Applying insights from psychological research

PURPOSE

Informed medical decision-making at the end of life often requires engaging in highly emotional, potentially upsetting discussions about prognosis, while ensuring that patients grasp its personal meaning. Behavioral science offers insights into ways to promote prognostic understanding among patients with advanced cancer.

SUMMARY

In this literature review, we synthesize complementary findings from basic behavioral science and applied clinical research, which suggest that psychological factors can significantly influence both patients' clinical interactions and their prognostic understanding. For example, stress and emotion can affect cognition, which may shape how patients process complex medical information. Additionally, clinicians may be less likely to share prognostic information with distressed patients who, in turn, may be hesitant to ask about their prognosis for fear of the answer. Although traditional approaches for increasing advanced cancer patients' understanding focus on improving information delivery, these efforts may not be sufficient without corresponding interventions that assist patients in managing distress.

CONCLUSIONS

Psychological barriers may limit opportunities for patients to fully understand their prognosis and to receive high quality of end-of-life care that is linked with an accurate understanding of their disease and treatment options. Failure to attend to patients' emotional distress may undermine efforts to improve medical communication. This underscores the importance of increased attention to the psychological factors that impede patients' comprehension of material shared in cancer clinic visits, in order to inform interventions that address patient distress both before and after receiving "bad news." Integrating findings from psychological research into prognostic discussions may not only improve advanced cancer patients' mental health, but may also promote their ability to make informed, value-consistent medical decisions.

Stress and the medial temporal lobe at rest: Functional connectivity is associated with both memory and cortisol

When acute stress is experienced immediately after memory encoding (i.e., post-encoding stress) it can significantly impact subsequent memory for that event. For example, recent work has suggested that post-encoding stress occurring in a different context from encoding impairs memory. However, the neural processes underlying these effects are poorly understood. We aimed to expand this understanding by conducting an analysis of resting functional connectivity in the period following post-encoding stress that occurred in a different context than encoding, using seed regions in the medial temporal lobes known for their roles in memory. In the current study of 44 males randomized to stress (n = 23) or control (n = 21) groups, we found that stress increased cortisol, impaired recollection of neutral materials, and altered functional connectivity with medial temporal lobe regions. Although stress did not significantly alter hippocampus-amygdala functional connectivity, relative to participants in the control group, participants in the post-encoding stress group showed lower functional connectivity between the hippocampus and a region with a peak in the superior temporal gyrus. Across participants in both groups, functional connectivity between these regions was related to greater increases in cortisol, and it was also inversely related to recollection of neutral materials. In contrast, the stress group showed greater parahippocampal cortex functional connectivity with a region in the left middle temporal gyrus than the control group. Moreover, greater functional connectivity between the parahippocampal cortex and the observed cluster in the middle temporal gyrus was associated with greater cortisol changes from pre- to post-manipulation, but was not related to differences in memory. The results show that post-encoding stress can alter the resting-state functional connectivity between the medial temporal lobe and neocortex, which may help explain how stress impacts memory.

The Power of Faith: The Influence of Athletes' Coping Self-Efficacy on the Cognitive Processing of Psychological Stress

Coping self-efficacy (CSE) has a positive mental health effect on athletes’ ability to cope with stress. To understand the mechanism underlying the potential impact of CSE, event-related potentials (ERPs) were used to explore the neural activity of the cerebral cortex under acute psychological stress in athletes with different CSE levels. Among 106 high-level athletes, 21 high-CSE athletes and 20 low-CSE athletes were selected to participate in the experiment. A mental arithmetic task was used to induce acute psychological stress. The results showed that high-CSE athletes responded more quickly than low-CSE athletes. In the stress response stage, the N1 peak latency of low-CSE athletes was longer than that of high-CSE athletes, and the N1 amplitude was significantly larger than that of high-CSE athletes. In the feedback stage, the FRN amplitude with error feedback of high-CSE athletes was larger than that of low-CSE athletes, and the P300 amplitude with correct feedback was larger than that with error feedback. The results indicate that high-CSE athletes can better cope with stressful events, adjust their behaviors in a timely manner according to the results of their coping, and focus more on processing positive information.

Prospective memory under acute stress: The role of (output) monitoring and ongoing-task demands

Prospective memory (PM) refers to the ability to postpone retrieval and execution of intended actions until the appropriate situation (PM cue) has come, while engaging in other ongoing activities or tasks. In everyday live we often perform PM tasks in stressful situations. While it has been shown that acute stress does not impair PM-cue identification and intention retrieval, little is known about acute stress effects on PM performance and memory for having performed an action (output monitoring) under varying ongoing-task demands. Here we investigated this in eighty healthy participants who performed event-based PM tasks during low- and high-demanding ongoing working memory tasks after having undergone either a standardized stress induction (Maastricht Acute Stress Test) or a standardized control protocol. Successful stress induction in the stress group compared to the no-stress group was confirmed by increased salivary cortisol, an indicator of stress-related hypothalamus-pituitaryadrenal axis activity, throughout the event-based PM tasks. Nevertheless, not-only PM-cue identification but also output monitoring remained fully intact after stress induction. The absence of these effects was independent of ongoing-task demands. Nonetheless, we replicated recent findings of a stress-induced reduction in performance cost of monitoring for PM-cue occurrences. Taken together our findings suggest that acute stress alters PM monitoring by enhancing selective attention, decreasing PM response thresholds or by shifting performance towards more automatic processes in PM, while not affecting PM-cue identification and output monitoring.

Enhancing memory with stress: Progress, challenges, and opportunities

Stress can strongly influence what we learn and remember, including by making memories stronger. Experiments probing stress effects on hippocampus-dependent memory in rodents have revealed modulatory factors and physiological mechanisms by which acute stress can enhance long-term memory. However, extending these findings and mechanisms to understand when stress will enhance declarative memory in humans faces important challenges. This review synthesizes human and rodent studies of stress and memory, examining translational gaps related to measurements of declarative memory and stress responses in humans. Human studies diverge from rodent research by assessing declarative memories that may not depend on the hippocampus and by measuring peripheral rather than central stress responses. This highlights opportunities for future research across species, including assessing stress effects on hippocampal-dependent memory processes in humans and relating peripheral stress responses to stress effects on the function of memory-related brain regions in rodents. Together, these investigations will facilitate the translation of stress effects on memory function from rodents to humans and inform interventions that can harness the positive effects of stress on long-term memory.

Memories of and influenced by the Trier Social Stress Test

Psychosocial stress influences cognition, affect and behavior. This current review summarizes the impact of acute stress on human long-term memory taking a neuroendocrine perspective. In this respect the stress associated increase in activity of the sympathetic nervous system (SNS) and the hypothalamus-pituitary-adrenal (HPA) axis are key. A special focus will be placed on findings obtained with the Trier Social Stress Test (TSST). This paradigm can be used to induce stress before or after a memory task. It was shown repeatedly that stress enhances long-term consolidation but impairs long term memory retrieval. However the TSST can also be used to assess memories of this stressful episode itself. The latter requires a standardized presentation of relevant stimuli during the TSST as well as a carefully designed control condition. Moreover special care has to be taken to control potential influences on visual exploration and working memory in order to correctly interpret observed effects on memory. The results obtained so far fit to the idea of enhanced encoding of salient information under stress. These findings are of relevance for educational, organizational and clinical applications.

Minority Stress, Emotion Regulation, and Executive Function: An Experimental Investigation of Gay and Lesbian Adults

Minority stress is associated with emotional, cognitive, and health consequences for sexual minority individuals. Mechanisms remain poorly understood. Theory and preliminary evidence suggests that stress associated with minority identity results in negative emotions and attempts at suppression, which may contribute to depletion of executive function. This study was an experimental investigation of gay and lesbian adults (N = 141). Participants engaged in a stressful interpersonal task with a confederate with anti-gay or pro-gay attitudes. We examined how condition affected executive function, along with potential mediators (state anger, anxiety, expressive suppression). Contrary to hypotheses, participants in the anti-gay condition showed better postmanipulation cognitive performance than the pro-gay condition. This effect was partially mediated by anger. Participants in the anti-gay condition reported greater attempts at suppression, but this variable did not emerge as a mediator. This study was the first to experimentally manipulate exposure to anti-gay attitudes and measure effects on executive function.

The role of the opioid system in decision making and cognitive control: A review

The opioid system regulates affective processing, including pain, pleasure, and reward. Restricting the role of this system to hedonic modulation may be an underestimation, however. Opioid receptors are distributed widely in the human brain, including the more "cognitive" regions in the frontal and parietal lobes. Nonhuman animal research points to opioid modulation of cognitive and decision-making processes. We review emerging evidence on whether acute opioid drug modulation in healthy humans can influence cognitive function, such as how we choose between actions of different values and how we control our behavior in the face of distracting information. Specifically, we review studies employing opioid agonists or antagonists together with experimental paradigms of reward-based decision making, impulsivity, executive functioning, attention, inhibition, and effort. Although this field is still in its infancy, the emerging picture suggests that the mu-opioid system can influence higher-level cognitive function via modulation of valuation, motivation, and control circuits dense in mu-opioid receptors, including orbitofrontal cortex, basal ganglia, amygdalae, anterior cingulate cortex, and prefrontal cortex. The framework that we put forward proposes that opioids influence decision making and cognitive control by increasing the subjective value of reward and reducing aversive arousal. We highlight potential mechanisms that might underlie the effects of mu-opioid signaling on decision making and cognitive control and provide directions for future research.

The effects of perceived chronic stress on the fMRI correlates of attentional control in women managers

The aims of the current study were to examine differences in brain responses to cognitive control in stressed and non-stressed women managers. Stress complaints are highly prevalent among active workers and play an important role in women managers mental health and cognitive functioning. Psychosocial stress has been associated with differential executive functions in this population, but little is known about the neural correlates underlying such differences. We examined brain responses of a particular group of workers that has been proposed to have a different response to stress as a function of their status (i.e., managers). Stressed (n = 19) and non-stressed women managers (n = 21) were scanned using functional magnetic resonance imaging (fMRI) during the performance of a cognitively demanding task. We used the Stroop color-word task to compare neural activation associated with the suppression of a predominant response tendency (i.e., word reading) and the initiation of an appropriate behavior alternative (i.e., naming word color). Despite similar behavioral performances, stressed managers exhibited increased activation in the occipital cortex during response inhibition. No regions were more activated in the non-stressed relative to the stressed group. This finding of greater activation has been interpreted as compensatory brain response to maintain performance in front of cognitive challenge.

Daily consumption of essence of chicken improves cognitive function: a systematically searched meta-analysis of randomized controlled trials

Essence of chicken (EC) is a dietary supplement with potential benefits on one's cognitive performance. The purpose of this meta-analysis is to evaluate the effects of consuming EC on cognitive function, applying extensively represented domains. Six databases were systematically searched to yield 1760 articles. These articles were independently screened to obtain 8 eligible articles with a pooled population of 794 subjects which is more than twice the population size considered in the previous meta-analyses. Largely, favorable effects on cognitive function were observed following daily EC intake, specifically in the working memory domain (standardized mean difference: 0.31, 95% CI: 0.16, 0.46), one of the core components in executive function which showed statistically significant results. Furthermore, the observed results were also robust to sensitivity analyses and subgroup analyses. This suggests that when consumed daily, EC may improve the mental processing aspect of cognitive function amongst the healthy population.

Systems pharmacogenomics - gene, disease, drug and placebo interactions: a case study in COMT

Disease, drugs and the placebos used as comparators are inextricably linked in the methodology of the double-blind, randomized controlled trial. Nonetheless, pharmacogenomics, the study of how individuals respond to drugs based on genetic substrate, focuses primarily on the link between genes and drugs, while the link between genes and disease is often overlooked and the link between genes and placebos is largely ignored. Herein, we use the example of the enzyme catechol-O-methyltransferase to examine the hypothesis that genes can function as pharmacogenomic hubs across system-wide regulatory processes that, if perturbed in andomized controlled trials, can have primary and combinatorial effects on drug and placebo responses.

Physical Activity versus Psychological Stress: Effects on Salivary Cortisol and Working Memory Performance

Background and Objective: The present study was designed to investigate whether acute physical activity and psychological stress produce different effects on cortisol release and working memory performance. Materials and Methods: Male subjects (N = 12; 18–35 years) were recruited and scheduled to come four times to our lab (within-subject design). For each counterbalanced visit, they performed one of the following four protocols: control, moderate physical activity (MOD), vigorous physical activity (VIG), and acute stress. Heart rate was monitored during every protocol. MOD and VIG were performed for 15 min and were defined as 40–50% and 70–80%, respectively, of their maximum heart rate. Acute stress was imposed via the Trier Social Stress Test (TSST). Salivary samples were collected before and after every protocol to assess cortisol concentrations. Working memory (WM) performance was evaluated through the 2N-Back task right after ending the protocol (early WM) and after a delay of 35 min (late WM). Results: VIG and stress, but not MOD, increased salivary cortisol concentrations. However, the increases of cortisol produced by VIG and stress were not significantly different. Also, there were no significant differences in working memory performance (late and early) in any of the experimental protocols tested. Conclusions: These results show that exercise (VIG) and stress produce similar effects on cortisol release and do not support the hypothesis that working memory capacity is influenced by elevated cortisol levels, either from varying exercise intensities or psychological stress.

Stress and prospective memory: What is the role of cortisol?

Studies investigating effects of acute stress on Prospective Memory (PM) so far yielded heterogeneous findings. Although results were commonly attributed to stress-induced changes in cortisol, past research did not disentangle effects of cortisol from the effects of sympathetic nervous system (SNS) activation and cognitive reappraisal. The present study therefore aimed at investigating the mere effect of cortisol on PM tasks that differently involve prefrontal brain regions (nonfocal vs. focal PM tasks) via a placebo-controlled oral pharmacological intake of 10 mg hydrocortisone mimicking physiological responses to stress. Contrary to our prediction, enhanced levels of cortisol did not affect PM accuracy and monitoring costs, neither for the focal nor the nonfocal PM tasks. These results suggest that changes of cortisol levels do not underlie potential stress effects on PM. Further exploratory results revealed that PM performance was higher in the 3 pm than in the 1 pm placebo group. This means that PM performance, independently of effects of cortisol, seem to vary throughout the day.

Transdiagnostic mechanisms of psychopathology in youth: Executive functions, dependent stress, and rumination

Executive function (EF) deficits have been proposed as transdiagnostic risk factors for psychopathology, and recent research suggests EF impairments are associated with what is shared across forms of psychopathology (p factor). However, most research has not employed methods that differentiate between EF components, and little is known about the mediating mechanisms linking EF and psychopathology dimensions. The current study tested associations between the latent unity/diversity model of EF and latent dimensions of psychopathology and investigated mediating mechanisms in a community sample of 292 youth age 13-22. The results confirmed the finding that poor EF is associated with internalizing psychopathology in older youth via higher dependent stress and rumination, and showed that this pathway was transdiagnostic, predicting the p factor rather than internalizing specifically. Links with psychopathology were specific to the common EF factor, rather than updating- or shifting-specific EF.

Retention of a standard operating procedure under the influence of social stress and refresher training in a simulated process control task

In a simulated process control task, we investigated the effects of refresher training and acute social stress on performing a standard operating procedure (SOP) containing a production and monitoring task and knowledge recall after a retention interval of two weeks. In a 2 × 2 between-group design (Factor 1: induced social stress, Factor 2: refresher training), 76 engineering students performed an SOP at t1 in week 1 and at t2 in week 3. A MANOVA in week three (t2) indicated a main effect of the refresher training for the SOP execution containing a production and a monitoring task and an impairing effect of stress on the monitoring task. That means that after a retention interval, stress mainly affects the SOP's monitoring task. An additional correlational analysis showed that knowledge test performance is negatively associated with cortisol level and that retentivity is a strong predictor for knowledge test performance and production task performance, too. Practitioner Summary: We investigated effects of social stress and refresher training on performing a standard operating procedure (SOP) after a retention interval of two weeks. The impact of social stress reduced the monitoring task performance as part of the SOP, but not the production outcome. Without refresher training, performance is significantly worse. Abbreviation: SOP: Standard Operating Procedure; MANOVA: Multivariate Analysis of Variance; CSB: Chemical Safety and Hazard Investigation Board; TSST: Trierer Social Stress Test; P-TSST: Placebo Trierer Social Stress Test; WaTrSim: Water Treatment Simulation; HPA axis: hypothalamic pituitary adrenal axis; WIT-2: Wilde Intelligenztest - 2; SPSS: Statistical Package for the Social Sciences; ANOVA: Analysis of Variance.

Factors in the perceived stress scale differentially associate with mindfulness disposition and executive function among early adolescents

OBJECTIVES

The first aim was to test the factor structure and item-loadings of the 10-item Perceived Stress Scale (PSS) when administered to early adolescents. The second aim was to examine associations between PSS factors, mindfulness disposition, and executive function.

METHODS

We analyzed data collected from 331 students in grade seven (M age=12.4, 48.9% female, 47.1% White, 26.0% Hispanic, 37.8% received free-lunch) classrooms from two ethnically/racially and socio-economically diverse schools. Participants completed paper and pencil self-report measures of stress (PSS), mindfulness disposition (Mindful Awareness Attention Scale, MAAS), and executive function (Behavior Rating Inventory of Executive Function, BRIEF). We tested the statistical association between two factors of the PSS: perceived coping and perceived distress with MAAS and BRIEF.

RESULTS

A two-factor model of the PSS, inclusive of perceived coping and perceived distress, fit the data better than a one-dimensional model. MAAS and BRIEF scores were inversely associated with PSS distress scores (β = -.62, p <.0001 and β = -.66, p <.0001, respectively), but not PSS coping scores (β = -.04, p = .21 and β = -.02, p = .57, respectively) in a model adjusted for sex, race, and socio-economic status.

CONCLUSIONS

Two factors in the PSS emerged among early adolescents and differentially associated with mindfulness disposition and executive function to similar magnitudes. Findings encourage future assessment of perceived stress in a more refined manner across developmental stages in order to examine trajectories of perceived distress versus perceived coping in relation to mindfulness disposition and executive function.

Influence of glucocorticoid and mineralocorticoid receptor stimulation on task switching

The influence of stress on executive functions has been demonstrated in numerous studies and is potentially mediated by the stress-induced cortisol release. Yet, the impact of cortisol on cognitive flexibility and task switching in particular remains equivocal. In this study, we investigated the influence of pharmacological glucocorticoid receptor (GR) and mineralocorticoid receptor (MR) stimulation, two corticosteroid receptor types known to be responsible for cortisol effects on the brain. We conducted two experiments, each with 80 healthy participants (40 women and 40 men), and tested the effect of the unspecific MR/GR agonist hydrocortisone (Experiment I) and the more specific MR agonist fludrocortisone (Experiment II) on switch costs and task rule congruency in a bivalent, cued task switching paradigm. The results did not confirm our hypotheses; we found no significant effects of our manipulations on task switching capacity, although general switching and congruency effects were observed. We discuss the absence of MR/GR-mediated effects and propose alternative mechanisms that could explain stress induced effects on task switching.

Determining the mechanisms through which recent life stress predicts working memory impairments: precision or capacity?

Prior research has found that recent life stress exposure is related to poorer working memory performance, but it remains unclear which aspects of working memory are related to stress. To address this important issue, we examined the extent to which recent life stress exposure was associated with working memory capacity (i.e., the number of items that can be held in working memory) and working memory precision (i.e., the quality of representations of items held within working memory) in a sample of 260 healthy young adults (M_age= 19.95 years old; range = 18-33). Recent life stress exposure and working memory were assessed with the Stress and Adversity Inventory for Daily Stress (Daily STRAIN) and color wheel task, respectively. We found that recent life stress was selectively associated with lower working memory capacity; moreover, the association of recent life stress with capacity was significantly stronger in magnitude than the non-significant association of recent life stress with precision. These associations were robust while controlling for potential confounds, including demographic factors, negative affect, and cumulative lifetime stress exposure. These results thus suggest that stress-related degradations in working memory capacity may help explain how recent life stress exposure affects working memory performance.

Acute stressor effects on cognitive flexibility: mediating role of stressor appraisals and cortisol

Acute stressor experiences may influence cognition, possibly through actions of cognitive flexibility, which comprises the ability to modify cognitive and behavioral strategies in response to changing environmental demands. In the present investigation, we examined the effects of an acute psychosocial stressor (the Trier Social Stress Test) on a specific form of cognitive flexibility, namely that of set-shifting, which was assessed by the Berg's Card Sorting Task (BCST). Among undergraduate students, the stressor promoted better performance on the BSCT relative to that evident among nonstressed individuals, including a reduction of perseverative (an index of enhanced set-shifting) and non-perseverative errors. They also required fewer trials to learn the first sorting category, reflecting augmented acquisition of an attentional set, but did not differ in the ability to maintain a set. Moreover, increased cortisol levels specifically mediated the enhancing effects of the acute stressor on set-shifting, but not the ability to acquire and maintain an attentional set. However, this enhancing effect was minimized among individuals who appraised the stressor as being uncontrollable. These data indicate that an acute, social-evaluative stressor can facilitate certain forms of cognitive flexibility, such as set-shifting. The present investigation also highlights the value of focusing on psychological and physiological mediators in determining the impact of stressful experiences on cognitive functioning. Lay summary A brief social stressor (public speaking) can have an enhancing effect on mental flexibility, and this seems to be related to the stress hormone, cortisol. This cognitive enhancing effect, however, might be minimized if a stressful situation is perceived as beyond a person's control.

Subjective and physiological stress measurement in a multiple sclerosis sample and the relation with executive functions performance

In multiple sclerosis (MS), hypothalamic-pituitary-adrenal (HPA) axis functioning may be dysregulated due to the high cortisol levels involved in the disease activity. HPA axis dysregulation can affect cognitive performance, including executive functions. This study aimed to evaluate hair cortisol concentration and perceived stress as well as verify the association with the performance of executive function in both individuals diagnosed with MS and control individuals. Hair cortisol concentration and perceived stress were evaluated and their association with the performance of healthy individuals (n = 33) and those with MS (n = 64), most of them with remitting-relapsing multiple sclerosis (RRMS) assessed using the Expanded Disability Status Scale (EDSS). Instruments that were employed to measure perceived stress and health aspects included the Behavioral Assessment Dysexecutive Syndrome, Wisconsin Card Sorting Test, Stroop Test, and Perceived Stress Scale. No significant statistical difference was found in the comparison of means among the groups; however, an association was found when using statistical correlation tests between cortisol and cognitive performance in the clinical group (r = 0.31, p = 0.10). Further, an absence of correlations with perceived stress measure was noted. It was possible to observe interaction between group factors and low level of cortisol and problem-solving/cognitive flexibility in the MS group. The results indicated that stress measures used in the present study seem to influence the performance of inhibitory control and problem-solving/cognitive flexibility, the latter with low levels of cortisol in individuals with MS. We suggest studies that examine different measures of physiological stress and characteristics of the disease such as more time of stress.

Associations between Anxiety, Poor Prognosis, and Accurate Understanding of Scan Results among Advanced Cancer Patients

Background: Routine imaging ("scan") results contain key prognostic information for advanced cancer patients. Yet, little is known about how accurately patients understand this information, and whether psychological states relate to accurate understanding. Objective: To determine if patients' sadness and anxiety, as well as results showing poorer prognosis, are associated with patients' understanding of scan results. Design: Archival contrasts performed on multi-institutional cohort study data. Subjects: Advanced cancer patients whose disease progressed after at least one chemotherapy regimen (N = 94) and their clinicians (N = 28) were recruited before an oncology appointment to discuss routine scan results. Measurements: In preappointment structured interviews, patients rated sadness and anxiety about their cancer. Following the appointment, patients and clinicians reported whether the imaging results discussed showed progressive, improved, or stable disease. Results: Overall, 68% of patients reported their imaging results accurately, as indicated by concordance with their clinician's rating. Accuracy was higher among patients whose results indicated improved (adjusted odds ratio [AOR] = 4.12, p = 0.02) or stable (AOR = 2.59, p = 0.04) disease compared with progressive disease. Patients with greater anxiety were less likely to report their imaging results accurately than those with less anxiety (AOR = 0.09, p = 0.003); in contrast, those with greater sadness were more likely to report their results accurately than those with less sadness (AOR = 5.23, p = 0.03). Conclusions: Advanced cancer patients with higher anxiety and those with disease progression may need more help understanding or accepting their scan results than others.

Differences in Coping Strategies Between Young and Older Adults: The Role of Executive Functions

Executive functions (EFs) have been identified as processes in the ability to select and apply adaptive strategies for coping with stress. This study compares executive functioning, short-term memory, and coping in a sample of young and older adults with no prior diagnosis of depression and with normal cognitive function ( N = 216). The study collected measures of depression, EFs, short-term memory, and coping. Young participants scored higher than older adults on EFs and short-term memory. Moreover, in young adults, there was a prevalence of avoidance coping strategies. Scores on depressive symptomatology were found to be related to avoidant coping strategies. Older adults with higher score on inhibition used less avoidant coping. Thus, it seems that executive deficits might contribute to depression, as they affect processes for coping with stress. This finding may have implications for the role of EFs and coping in psychological well-being and successful adaptation of individuals to stressful situations.

Psychophysiological stress response and memory in borderline personality disorder

Background: Previously, we found that patients with borderline personality disorder (BPD) but not healthy controls (HC) showed improved memory retrieval after hydrocortisone administration. Objective: In this study, we examined whether increases in endogenous cortisol after psychosocial stress are associated with memory function in patients with BPD and in healthy individuals. Methods: We recruited 49 female patients with BPD and 49 female HC. All participants were exposed to a psychosocial stressor, the Trier Social Stress Test (TSST) and a control condition (Placebo (P-)TSST) in randomized order. Salivary cortisol, alpha amylase (sAA) and blood pressure were measured in response to stress. Subsequently, we examined free recall of a previously learned word list, autobiographical memory, and working memory. Results: We found a stress*time*group interaction effect for the cortisol response and for sAA to stress, which is mainly triggered by a slightly different increase in cortisol between groups from pre to post TSST. Furthermore, BPD patients showed a less pronounced increase in diastolic blood pressure compared to HC after stress. There was no effect of stress on memory performance in any tests, either in healthy controls or in patients with BPD. Conclusion: Our results suggest a slightly blunted response of the HPA axis and the sympathetic nervous system to stress in BPD compared to healthy women. In contrast to hydrocortisone administration, psychosocial stress did not improve memory retrieval in BPD patients. This might be explained by lower cortisol concentrations and parallel increases in norepinephrine and negative affect after stress.

Developmental influences on stress response systems: Implications for psychopathology vulnerability in adolescence

The adolescent transition is marked by increases in stress exposure and significant maturation of neural and hormonal stress processing systems. Variability in the development of these systems during adolescence may influence the risk for stress-related psychopathology. This paper aims to review the developmental maturation of the HPA axis and related stress regulation systems, and demonstrate how interference in this adaptive developmental process may increase the risk for negative outcomes. We argue that the developmental maturation of the HPA axis aims to improve the regulatory capacity of the axis in order to more adaptively respond to these increases in stress reactivity. Additionally, we review evidence that sex differences in the development of the HPA and related axes may contribute to sex differences in the risk for stress-related psychopathology. Finally, we discuss how contextual factors, such as early trauma and obesity may alter the development of HPA axis during the adolescence transition and how alterations of normative development increase the risk for stress-related disorders.

Healthy aging: A bibliometric analysis of the literature

Due to dramatic growth of the aging population worldwide, there has been an urgent call for a public health strategy to manage healthy aging, with the ultimate goal being advancement of aging research. Considerable progress has been made in uncovering the mystery of aging process using multidisciplinary methods. There is a growing consensus in the field that aging traits which were originally thought to be disparate are likely to be interconnected. Thus, emerging research is needed to incorporate current findings of aging by building multiscale network models. This study reported the network of healthy aging research using bibliometric approaches. Based on the results, aging of the brain and muscle is a primary research focus which is a critical part of the multiscale network regulating the aging process. Among aging-associated diseases, Alzheimer's disease and frailty are among the main research focuses, and emerging work has focused on developing diagnostic tools for these diseases. For research on anti-aging interventions, calorie restriction, physical activity, and anti-aging pharmacology are the main interventions, of which the underlying mechanisms have been comprehensively studied in animal models.

Feel free to write this down: Writing about a stressful experience does not impair change detection task performance

Acute stress impairs working memory (i.e., the ability to update and keep information in mind). Although that effect is well established, the boundaries around it are not. In particular, little is known about how recalling an unresolved stressor might influence working memory, or about how stress-or recalling a stressful event-influences the processes underlying working memory task performance (e.g., sustained/controlled attention vs. capacity). We addressed these issues in the present study (N = 171) by randomly assigning participants to write about an unresolved, extremely stressful experience (stressful writing condition; n = 85) or the events of the prior day (control condition; n = 86), and, subsequently, both measured change detection task performance and used computational cognitive modeling to estimate the processes underlying it-namely, attention, capacity, and bias. We found that, relative to the control task, writing about a stressful experience neither impaired performance on the change detection task nor altered any of the processes underlying performance on that task. These results show that the effects of writing about an unresolved, stressful episode do not parallel effects of acute stress on working memory, indicating that experiencing a stressor may have very different cognitive effects than recalling it at a later time. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

What's going on in my baby's mind? Mothers' executive functions contribute to individual differences in maternal mentalization during mother-infant interactions

Maternal mentalization refers to a mother's capacity to understand mental-states of herself and her child and to regard her child as a psychological agent. In mother-infant interactions, this capacity is commonly conceptualized as maternal mind-mindedness, which can be divided into two dimensions: appropriate and nonattuned interpretations of the infants' mental-states. Appropriate mind-mindedness refers to interpretations that seem to be compatible with the infant's behaviors, whereas nonattuned mind-mindedness refers to noncompatible interpretations. The aim of this study was to investigate the cognitive mechanisms that contribute to mind-mindedness. Specifically, we investigated the role of executive functions in appropriate and nonattuned mind-mindedness, and the moderating roles of two infant-related factors, prematurity (as a stressful context) and child temperament (as a context of unpredictability and negative emotionality). To this end, mother-infant free play interactions were coded for mind-mindedness in a sample of 102 mothers and their 6-month-old infants (61 preterm, 41 full-term). When children were 66-months old, mothers completed cognitive tasks that assessed working memory updating, resistance to interference, response inhibition, and shifting. Appropriate mind-mindedness was positively associated with updating, and this link was stronger when infant temperament was rated as more difficult. Furthermore, among mothers of full-term infants, mothers' resistance to interference was negatively associated with nonattuned mind-mindedness. This link was not evident in the stressful context of premature birth. Mothers' response inhibition and shifting were not associated with either of the mind-mindedness dimensions. Implications on understanding variability in maternal mentalization during mother-infant interactions and the roles of executive functions in parenting are discussed.

Cortisol Impacted on Explicit Learning Encoding, but Not on Storage and Retrieval, and Was Not Associated With Sleep Patterns-Results From the Trier Social Stress Test for Children (TSST-C) Among 9-Years Old Children

Background: Learning is the relatively permanent change of behavior as a result of experience and tightly related to memory and cognition. Learning is particularly important for children. Further, restoring sleep is associated both with improved learning performance and lower cortisol levels as a proxy of the so-called hypothalamus-pituitary-adrenocortical axis activity (HPA-AA). With the present study, we investigated, if and to what extent explicit learning performance was associated with cortisol levels at baseline and under challenge conditions and with objective sleep dimensions among 9-years old children.

Methods: A total of 39 children (mean age = 9.5 years; 39% females) took part in the study. Verbal and figural working and long-term memory were tested before and after the Trier Social Stress Test for Children (TSST-C). Further, children underwent sleep-EEG assessment, and cortisol awakening response (CAR) was assessed.

Results: Higher cortisol levels were associated with lower explicit learning encoding (verbal, but not figural learning). Higher verbal and figural working and long-term memory performance predicted lower cortisol secretion under the TSST-C, along with higher verbal and figural working and long-term memory performance after the TSST-C. Cognitive test performances were not mediated by cortisol secretion under the TSST-C. Cognitive performance, cortisol secretion under challenge (TSST-C) and basal conditions (morning) and sleep patterns were unrelated.

Conclusions: The pattern of results suggests that among a sample of 9-years old children cortisol secretion and stages of memory processes (encoding, storage, retrieval) are associated in a complex and bi-directional way. Further, it appears that cognitive-emotional processes underlying cognitive performance and its evaluation might impact on subsequent cortisol secretion as a proxy of neuroendocrinological response to cognitive-emotional processes. Last, cognitive performance and cortisol secretion under challenge conditions were not related to objective sleep patterns and baseline cortisol secretion.

Cognitive Control and Flexibility in the Context of Stress and Depressive Symptoms: The Cognitive Control and Flexibility Questionnaire

Cognitive control and (cognitive) flexibility play an important role in an individual's ability to adapt to continuously changing environments. In addition to facilitating goal-directed behaviors, cognitive control and flexibility have been implicated in emotion regulation, and disturbances of these abilities are present in mood and anxiety disorders. In the context of stressful experiences, the reported studies examined processes related to cognitive control and flexibility, emotional regulation and depressive symptoms. To this end, a brief (18-item) self-report measure - the Cognitive Control and Flexibility Questionnaire (CCFQ) - was developed. This questionnaire measures an individual's perceived ability to exert control over intrusive, unwanted (negative) thoughts and emotions, and their ability to flexibly cope with a stressful situation. In Study 1, the CCFQ was assessed among both university students (N = 300) and a community sample (N = 302). Preliminary analyses suggested a stable and reliable two-factor structure, that of cognitive control over emotion, and appraisal and coping flexibility. Scores on the CCFQ were strongly associated with greater depressive symptoms, even after controlling for other measures that had been taken to reflect cognitive control and (in)flexibility (e.g., the Ruminative Response Scale; Perseverative Thinking Questionnaire). In Study 2 (N = 368), lower scores on the CCFQ were related to more negative stressor appraisals (i.e., greater perceived threat and uncontrollability) of a personally meaningful stressful event. Perceptions of threat and uncontrollability, in turn, partially accounted for the association between CCFQ subscale scores and depressive symptoms. The relation between lower CCFQ scores and heightened depressive symptoms was also partially accounted for by less frequent engagement in problem-focused coping and more use of emotion-focused methods. In Study 3 (N = 47 females), lower scores on the cognitive control over emotion component of the CCFQ predicted elevated negative affect and an exacerbated cortisol response following an acute psychosocial stressor (Trier Social Stress Test). The present research points to the CCFQ as a useful self-report tool to identify ways through which cognitive control and flexibility might be manifested in stressful situations, and how reductions in flexibility might be accompanied by elevated symptoms of depression.

Distress intolerance moderation of neurophysiological markers of response inhibition after induced stress: Relations with cannabis use disorder

Cannabis use is prevalent but only a minority of regular users develop cannabis use disorder (CUD); thus, CUD risk identification among current cannabis users is vital for targeted intervention development. Existing data suggest that high distress intolerance (DI), an individual difference reflective of the ability to withstand negative affect, is linked to CUD, possibly via stress-elicited impairment of response inhibition but this has never been explicitly tested. Frequent cannabis users with high and low DI completed a go/no-go task during EEG recording before and after a laboratory stressor. Relations between DI, cannabis use-related problems, and behavioral as well as neurophysiological markers of response inhibition functioning were assessed. DI significantly moderated the effect of the stressor on the conflict-monitoring but not evaluative phase of response inhibition as measured by N2 and P3a amplitude, respectively. Unexpectedly, cannabis users with high DI demonstrated stressor-elicited enhancement rather than impairment of conflict-monitoring neural activity, which was related to faster reaction time (RT) and decreased past-month cannabis problems. Enhanced inhibition-related modulation of P3a amplitude was generally associated with increased cannabis problems regardless of acute stress. Results did not provide support for stress-elicited impairment in cognitive control as a mechanism linking high DI and CUD, though some support was found for the relevance of inhibition-related neural activity to CUD. Stress-elicited enhancement of conflict-monitoring neural activity during response inhibition may reflect an adaptive neural response among cannabis users with high DI that protects against CUD in this at-risk group. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Stress and executive control: Mechanisms, moderators, and malleability

Stress pervades everyday life and more importantly, affects prefrontal cortices that support executive control functions, processes that are critical to learning and memory as well as a range of life outcomes. The positive or negative effect of stress on cognition depends on an interaction of factors related to the situation and the individual. Research has shown that psychological characteristics related to self-relevance and the availability of resources may lead individuals to perceive a stressor as a threat or challenge, driving performance outcomes. Given that perception is arguably the key to stress reactivity, positive affect and self-belief constructs are discussed in the context of how they may lead to preserved performance in the face of stress. Understanding the underlying mechanisms of stress perception could inform the development of interventions, a socially important endeavor given the impact of stress on health and cognitive functions.

Acute Stress Attenuates Cognitive Flexibility in Males Only: An fNIRS Examination

Cognitive processes that afford us the ability to control thoughts and achieve goal-directed behavior are known as executive functions. Empirical evidence in the past few years has demonstrated that executive functions can be influenced by acute stress. The impact of acute stress on cognitive flexibility, a key aspect of executive functions, has received little attention in the literature. We present the results of two experiments conducted to examine the effect of acute stress on cognitive flexibility. Acute stress was induced using the cold pressor task. Cognitive flexibility was assessed using the Wisconsin Card Sorting Test (WCST). Across both experiments acute stress had an attenuating effect on task switching on the WCST. Our findings also indicate that this effect was moderated by the participant’s gender. In Study 1, we observed that following stress exposure male participants in the stress condition made more perseverative errors than participants in the control group. In Study 2, we examined the bilateral hemodynamics in the prefrontal cortex (PFC) during acute stress induction using functional near infrared spectroscopy (fNIRS). Our analysis indicated that functional oxyHb signals fluctuated with greater amplitude than systemic components for participants in the stress group relative to those in the control group. In addition, oxyHb levels post stress induction were correlated with performance on the WCST for the male participants in the stress group only. Concordant with previous reports, our findings indicate that acute stress impacts cognitive flexibility in males and females differentially. Our work also demonstrates the feasibility of using fNIRS as a practical and objective technique for the examination of hemodynamics in the PFC during acute stress.

Reduced Stroop interference under stress: Decreased cue utilisation, not increased executive control

Since the 1960s, researchers have been reporting that stress reduces Stroop interference. This is puzzling, as stress and anxiety typically have deleterious effects on cognitive control and performance. The traditional explanation is that stress reduces "cue utilisation": It withdraws attentional resources from less relevant stimuli (including the distracter word), meaning that the target colour is left with a stronger influence over response selection. However, it could also be that stress somehow boosts distracter inhibition, or some other aspect of executive control. To test these two accounts, 59 students completed a Stroop task featuring occasional startlingly loud sounds (high stress) or the same sounds at a lower, comfortable volume (low stress). Alongside standard Stroop interference, two measures of executive control-negative priming and conflict adaptation-were calculated from the Stroop data. Stress produced a clear reduction of Stroop interference, but it did not influence negative priming, and no conflict adaptation effects were detected at all. These findings support the cue utilisation account. Furthermore, for the first time, stress was shown to reduce Stroop interference in a task with no congruent trials, showing that the effect does not result from stress's modulating any strategy changes participants might make in response to congruent trials.