Emotional stress regulation: The role of relative frontal alpha asymmetry in shaping the stress response

Frontal alpha asymmetry is associated with chronic stress and depression, but not with somatoform disorders

Cardinal characteristics of somatoform disorders (SFDs) are worry of illness, and impaired affective processing. We used relative frontal alpha asymmetry (FAA), a method to measure functional lateralization of affective processing, to investigate psychobiological correlates of SFDs. With alpha activity being inversely related to cortical network activity, relative FAA refers to alpha activity on the right frontal lobe minus alpha activity on the left frontal lobe. Less relative left frontal activity, reflected by negative FAA scores, is associated with lower positive and greater negative affectivity, such as observed in depression. Due to its negative affective component (illness anxiety), we expected to find less relative left frontal activity pattern in SFDs, and positive associations with self-reported chronic stress and depression symptoms. We recorded resting-state EEG activity with 64 electrodes, placed in a 10-10 system in 26 patients with a primary SFD, 23 patients with a major depressive disorder and 25 healthy control participants. The groups did not differ in FAA. Nevertheless, across all participants, less relative left frontal activity was associated with chronic stress and depression symptoms. We concluded that FAA may not serve as an indicator of SFDs. As the relationship of FAA and depressive symptoms was fully mediated by chronic stress, future studies have to clarify whether the association between FAA and chronic stress may represent a shared underlying factor for the manifestation of mental health complaints, such as depression.

Stress Responses Among Individuals with Spiritual Struggles in Hungary: An Experimental Study

Individuals with a Religious or Spiritual Problem (RSP), as defined in the DSM-5, experience distress associated with faith-related moral dilemmas, existential meaning, and transpersonal attitudes toward other people. It is unclear whether a RSP reflects a generally heightened stress reactivity or whether the stress response is confined to religious and spiritual contexts. To elucidate this issue, we measured behavioral and physiological responses during social-evaluative stress (public speaking-Trier Social Stress Test) and in religious/spiritual contexts (Bible reading and listening to sacred music) in 35 individuals with RSP and 35 matched participants. We found no stress reduction in the religious/spiritual context in RSP, as indicated by increased heart rate, saliva cortisol, and relatively higher left than right frontal activity. Religious stimuli evoked physiological stress responses in RSP. Contrary to the physiological parameters, participants with RSP reported less anxiety in the religious/spiritual context. Religious individuals with and without RSP showed similar stress responses during public speaking. Religious individuals without RSP displayed reduced stress responses in the religious/spiritual context. These results indicate that specific physiological distress in religious/spiritual contexts should be considered in the psychological care of RSP.

Association between preoperative frontal electroencephalogram alpha asymmetry and postoperative quality of recovery: an observational study

BACKGROUND

Left-sided frontal alpha asymmetry on electroencephalograms, which indicates decreased relative left-hemispheric activity, has been associated with depression, anxiety, and stress responsivity. We aimed to evaluate the association between perioperative measures of frontal alpha asymmetry and quality of recovery (QoR) after surgery.

METHODS

We enrolled 110 female patients undergoing thyroidectomy and recorded perioperative electroencephalograms. The power of the prefrontal alpha band (8-13 Hz) was measured in the Fp1 and Fp2 leads. Left-sided frontal alpha asymmetry was defined as a higher alpha band power in Fp1 than in Fp2 and vice versa. QoR was assessed using the QoR-15 score on the day before surgery and postoperative days 1 and 2. The primary study endpoint was a difference in postoperative global QoR-15 score between preoperative left-sided and right-sided alpha asymmetry groups. The predictability of frontal alpha asymmetry for poor QoR-15 score was also evaluated.

RESULTS

The global QoR-15 score showed a significant group-by-time interaction, and post-hoc analysis revealed significantly lower scores on postoperative days 1 (P=0.006) and 2 (P<0.001) in the left-sided frontal alpha asymmetry group. In the multivariate logistic regression analysis, preoperative left-sided frontal alpha asymmetry was associated with a 3.3-fold increased risk of the lowest tertile for the postoperative day 1 QoR-15 score (95% CI: 1.31-8.24; P=0.011).

CONCLUSIONS

Preoperative left-sided frontal alpha asymmetry was independently associated with a lower postoperative QoR-15 score in female patients undergoing thyroidectomy, highlighting the potential role of preoperative frontal electroencephalography in predicting patient-centred outcomes after surgery.

CLINICAL TRIAL REGISTRATION

KCT0006586 (http://cris.nih.go.kr/).

Older and Wiser? Age-related Change in State and Trait Boredom During Adolescence and Associations with Neural Correlates of Self-regulation

Purpose

The purpose of the current study was to examine age-related change in state and trait boredom in 12- to 17-year-old adolescents and test whether neurophysiological correlates of self-regulation relate to boredom during adolescence in the same way that has been found in adults.

Methods

Eighty-nine 12- to 17-year-old adolescents participated. Three types of trait boredom were measured: boredom proneness, leisure boredom, and boredom susceptibility. State boredom was also measured after completing a boredom induction task while EEG was recorded. Slopes in frontal alpha asymmetry (FAA) were extracted from the EEG as a measure of approach (leftward shifts) or avoidance (rightward shifts).

Results

A curvilinear relationship between age and boredom proneness and age and boredom susceptibility was observed, indicating trait boredom rises and falls across adolescence. State boredom, by contrast, increased linearly with age. Slopes in FAA inversely related only to boredom proneness, indicating higher levels of this type of trait boredom related to an avoidant response as a state of boredom ensues.

Conclusion

We suggest the rise and fall of trait boredom across adolescence may be due to changes in person-environment fit during middle adolescence, whereas state boredom may increase with age due to improvements in attentional processes that mundane lab tasks do not satisfactorily engage. The link between FAA and only one type of trait boredom indicates self-regulatory processes and boredom are not yet strongly coupled in adolescence. Implications for prevention of negative behavioral health outcomes associated with high levels of trait boredom are discussed.

Habituation of the stress response multiplex to repeated cold pressor exposure

Humans show remarkable habituation to aversive events as reflected by changes of both subjective report and objective measures of stress. Although much experimental human research focuses on the effects of stress, relatively little is known about the cascade of physiological and neural responses that contribute to stress habituation. The cold pressor test (CPT) is a common method for inducing acute stress in human participants in the laboratory; however, there are gaps in our understanding of the global state changes resulting from this stress-induction technique and how these responses change over multiple exposures. Here, we measure the stress response to repeated CPT exposures using an extensive suite of physiologic measures and state-of-the-art analysis techniques. In two separate sessions on different days, participants underwent five 90 s CPT exposures of both feet and five warm water control exposures, while electrocardiography (ECG), impedance cardiography, continuous blood pressure, pupillometry, scalp electroencephalography (EEG), salivary cortisol and self-reported pain assessments were recorded. A diverse array of adaptive responses are reported that vary in their temporal dynamics within each exposure as well as habituation across repeated exposures. During cold-water exposure there was a cascade of changes across several cardiovascular measures (elevated heart rate (HR), cardiac output (CO) and Mean Arterial Pressure (MAP) and reduced left ventricular ejection time (LVET), stroke volume (SV) and high-frequency heart rate variability (HF)). Increased pupil dilation was observed, as was increased power in low-frequency bands (delta and theta) across frontal EEG electrode sites. Several cardiovascular measures also habituated over repeated cold-water exposures (HR, MAP, CO, SV, LVET) as did pupil dilation and alpha frequency activity across the scalp. Anticipation of cold water induced stress effects in the time-period immediately prior to exposure, indexed by increased pupil size and cortical disinhibition in the alpha and beta frequency bands across central scalp sites. These results provide comprehensive insight into the evolution of a diverse array of stress responses to an acute noxious stressor, and how these responses adaptively contribute to stress habituation.

Assessing Electroencephalography as a Stress Indicator: A VR High-Altitude Scenario Monitored through EEG and ECG

Over the last decade, virtual reality (VR) has become an increasingly accessible commodity. Head-mounted display (HMD) immersive technologies allow researchers to simulate experimental scenarios that would be unfeasible or risky in real life. An example is extreme heights exposure simulations, which can be utilized in research on stress system mobilization. Until recently, electroencephalography (EEG)-related research was focused on mental stress prompted by social or mathematical challenges, with only a few studies employing HMD VR techniques to induce stress. In this study, we combine a state-of-the-art EEG wearable device and an electrocardiography (ECG) sensor with a VR headset to provoke stress in a high-altitude scenarios while monitoring EEG and ECG biomarkers in real time. A robust pipeline for signal clearing is implemented to preprocess the noise-infiltrated (due to movement) EEG data. Statistical and correlation analysis is employed to explore the relationship between these biomarkers with stress. The participant pool is divided into two groups based on their heart rate increase, where statistically important EEG biomarker differences emerged between them. Finally, the occipital-region band power changes and occipital asymmetry alterations were found to be associated with height-related stress and brain activation in beta and gamma bands, which correlates with the results of the self-reported Perceived Stress Scale questionnaire.

Individual differences in frontal alpha asymmetry moderate the relationship between acute stress responsivity and state and trait anxiety in adolescents

Stress is a risk factor in the development and maintenance of psychopathology, particularly anxiety. Despite theory suggesting differences in stress responsivity may explain heterogeneity in anxiety, findings remain contradictory. This may be due to failure to account for individuals' neurobiological states and outdated methodologic analyses which confound conceptually and biologically distinct stress response pathways. In 145 adolescents, this study examined whether individual differences in neural activation underlying motivational states, indexed by resting frontal alpha asymmetry (FAA) before and after the Trier Social Stress Test (TSST), moderate the relationship between stress responsivity (measured by cortisol) and anxiety. Adolescents with rightward FAA activation (indexed by changes in resting FAA pre-to-post TSST) and high trait anxiety showed blunted cortisol reactivities while those with leftward FAA activation and high state anxiety showed prolonged cortisol recoveries. Our work reveals individual differences in vulnerability to psychosocial stressors and is the first study to show that FAA activation moderates the relationships between anxiety and distinct phases of the stress response in adolescents.

Separating EEG correlates of stress: Cognitive effort, time pressure, and social-evaluative threat

The prefrontal cortex is a key player in stress response regulation. Electroencephalographic (EEG) responses, such as a decrease in frontal alpha and an increase in frontal beta power, have been proposed to reflect stress-related brain activity. However, the stress response is likely composed of different parts such as cognitive effort, time pressure, and social-evaluative threat, which have not been distinguished in previous studies. This distinction, however, is crucial if we aim to establish reliable tools for early detection of stress-related conditions and monitoring of stress responses throughout treatment. This randomized cross-over study (N = 38) aimed to disentangle EEG correlates of stress. With linear mixed models accounting for missing values in some conditions, we found a decrease in frontal alpha and increase in beta power when performing the Paced Auditory Serial Addition Test (PASAT; cognitive effort; n = 32) compared to resting state (n = 33). No change in EEG power was found when the PASAT was performed under time pressure (n = 29) or when adding social-evaluative threat (video camera; n = 29). These findings suggest that frontal EEG power can discriminate stress from resting state but not more fine-grained differences of the stress response.

Acute stress increases left hemispheric activity measured via changes in frontal alpha asymmetries

Frontal EEG alpha band asymmetries have been linked to affective processing in healthy individuals and affective disorders. As stress provides a strong source of negative affect, the present study investigated how acute stress affects frontal EEG alpha asymmetries. Continuous EEG data were acquired from 51 healthy adult participants during stress induction with the Trier Social Stress Test. EEG data were also collected during a non-stressful control condition. Furthermore, EEG resting state data were acquired after both conditions. Under stress, participants showed stronger left hemispheric activation over frontal electrodes as well as reduced left-hemispheric activation over occipital electrodes compared to the control condition. Our results are in line with predictions of the asymmetric inhibition model which postulates that the left prefrontal cortex inhibits negative distractors. Moreover, the results support the capability model of emotional regulation which states that frontal asymmetries during emotional challenge are more pronounced compared to asymmetries during rest.

•

EEG recording during social stress induction

•

Stronger left hemispheric frontal activation during emotional challenge

•

No stress-related changes in resting state EEG after stress induction

•

Support for asymmetric inhibition and the capability model of emotional regulation

Limb Preference in Animals: New Insights into the Evolution of Manual Laterality in Hominids

Until the 1990s, the notion of brain lateralization—the division of labor between the two hemispheres—and its more visible behavioral manifestation, handedness, remained fiercely defined as a human specific trait. Since then, many studies have evidenced lateralized functions in a wide range of species, including both vertebrates and invertebrates. In this review, we highlight the great contribution of comparative research to the understanding of human handedness’ evolutionary and developmental pathways, by distinguishing animal forelimb asymmetries for functionally different actions—i.e., potentially depending on different hemispheric specializations. Firstly, lateralization for the manipulation of inanimate objects has been associated with genetic and ontogenetic factors, with specific brain regions’ activity, and with morphological limb specializations. These could have emerged under selective pressures notably related to the animal locomotion and social styles. Secondly, lateralization for actions directed to living targets (to self or conspecifics) seems to be in relationship with the brain lateralization for emotion processing. Thirdly, findings on primates’ hand preferences for communicative gestures accounts for a link between gestural laterality and a left-hemispheric specialization for intentional communication and language. Throughout this review, we highlight the value of functional neuroimaging and developmental approaches to shed light on the mechanisms underlying human handedness.

Multi-Parameter Physiological State Monitoring in Target Detection Under Real-World Settings

Mental state changes induced by stimuli under experimental settings or by daily events in real life affect task performance and are entwined with physical and mental health. In this study, we developed a physiological state indicator with five parameters that reflect the subject's real-time physiological states based on online EEG signal processing. These five parameters are attention, fatigue, stress, and the brain activity shifts of the left and right hemispheres. We designed a target detection experiment modified by a cognitive attention network test for validating the effectiveness of the proposed indicator, as such conditions would better approximate a real chaotic environment. Results demonstrated that attention levels while performing the target detection task were significantly higher than during rest periods, but also exhibited a decay over time. In contrast, the fatigue level increased gradually and plateaued by the third rest period. Similar to attention levels, the stress level decreased as the experiment proceeded. These parameters are therefore shown to be highly correlated to different stages of the experiment, suggesting their usage as primary factors in passive brain-computer interfaces (BCI). In addition, the left and right brain activity indexes reveal the EEG neural modulations of the corresponding hemispheres, which set a feasible reference of activation for an active BCI control system, such as one executing motor imagery tasks. The proposed indicator is applicable to potential passive and active BCI applications for monitoring the subject's physiological state change in real-time, along with providing a means of evaluating the associated signal quality to enhance the BCI performance.

Enhancing EEG-Based Mental Stress State Recognition Using an Improved Hybrid Feature Selection Algorithm

In real-life applications, electroencephalogram (EEG) signals for mental stress recognition require a conventional wearable device. This, in turn, requires an efficient number of EEG channels and an optimal feature set. This study aims to identify an optimal feature subset that can discriminate mental stress states while enhancing the overall classification performance. We extracted multi-domain features within the time domain, frequency domain, time-frequency domain, and network connectivity features to form a prominent feature vector space for stress. We then proposed a hybrid feature selection (FS) method using minimum redundancy maximum relevance with particle swarm optimization and support vector machines (mRMR-PSO-SVM) to select the optimal feature subset. The performance of the proposed method is evaluated and verified using four datasets, namely EDMSS, DEAP, SEED, and EDPMSC. To further consolidate, the effectiveness of the proposed method is compared with that of the state-of-the-art metaheuristic methods. The proposed model significantly reduced the features vector space by an average of 70% compared with the state-of-the-art methods while significantly increasing overall detection performance.

Dichotic listening performance and interhemispheric integration after administration of hydrocortisone

Chronic stress has been shown to have long-term effects on functional hemispheric asymmetries in both humans and non-human species. The short-term effects of acute stress exposure on functional hemispheric asymmetries are less well investigated. It has been suggested that acute stress can affect functional hemispheric asymmetries by modulating inhibitory function of the corpus callosum, the white matter pathway that connects the two hemispheres. On the molecular level, this modulation may be caused by a stress-related increase in cortisol, a major stress hormone. Therefore, it was the aim of the present study to investigate the acute effects of cortisol on functional hemispheric asymmetries. Overall, 60 participants were tested after administration of 20 mg hydrocortisone or a placebo tablet in a cross-over design. Both times, a verbal and an emotional dichotic listening task to assess language and emotional lateralization, as well as a Banich-Belger task to assess interhemispheric integration were applied. Lateralization quotients were determined for both reaction times and correctly identified syllables in both dichotic listening tasks. In the Banich-Belger task, across-field advantages were determined to quantify interhemispheric integration. While we could replicate previously reported findings for these tasks in the placebo session, we could not detect any differences in asymmetry between hydrocortisone and placebo treatment. This partially corroborates the results of a previous study we performed using social stress to induce cortisol increases. This suggests that an increase in cortisol does not influence dichotic listening performance on a behavioral level. As other studies reported an effect of stress hormones on functional hemispheric asymmetries on a neuro-functional level, future research using neuronal imaging methods would be helpful in the characterization of the relation of hemispheric asymmetries and stress hormones.

Frontal and parietal EEG alpha asymmetry: a large-scale investigation of short-term reliability on distinct EEG systems

EEG resting-state alpha asymmetry is one of the most widely investigated forms of functional hemispheric asymmetries in both basic and clinical neuroscience. However, studies yield inconsistent results. One crucial prerequisite to obtain reproducible results is the reliability of the index of interest. There is a body of research suggesting a moderate-to-good reliability of EEG resting-state alpha asymmetry, but unfortunately sample sizes in these studies are typically small. This study presents the first large-scale short-term reliability study of frontal and parietal EEG resting-state alpha asymmetry. We used the Dortmund Vital Study data set containing 370 participants. In each participant, EEG resting state was recorded eight times, twice with their eyes opened, twice with their eyes-closed, each on two different EEG systems. We found good reliability of EEG alpha power and alpha asymmetry on both systems for electrode pairs. We also found that alpha power asymmetry reliability is higher in the eyes-closed condition than in the eyes-open condition. The frontomedial electrode pair showed weaker reliability than the frontolateral and parietal electrode pairs. Interestingly, we found no population-level alpha asymmetry in frontal electrodes, one of the most investigated electrode sites in alpha asymmetry research. In conclusion, our results suggest that while EEG alpha asymmetry is an overall reliable measure, frontal alpha asymmetry should be assessed using multiple electrode pairs.

Stress Analysis Based on Simultaneous Heart Rate Variability and EEG Monitoring

OBJECTIVE

Stress is a significant risk factor for various diseases such as hypertension, heart attack, stroke, and even sudden death. Stress can also lead to psychological and behavioral disorders. Heart rate variability (HRV) can reflect changes in stress levels while other physiological factors, like blood pressure, are within acceptable ranges. Electroencephalogram (EEG) is a vital technique for studying brain activities and provides useful data regarding changes in mental status. This study incorporates EEG and a detailed HRV analysis to have a better understanding and analysis of stress. Investigating the correlation between EEG and HRV under stress conditions is valuable since they provide complementary information regarding stress.

METHODS

Simultaneous electrocardiogram (ECG) and EEG recordings were obtained from fifteen subjects. HRV /EEG features were analyzed and compared in rest, stress, and meditation conditions. A one-way ANOVA and correlation coefficient were used for statistical analysis to explore the correlation between HRV features and features extracted from EEG.

RESULTS

The HRV features LF (low frequency), HF (high frequency), LF/HF, and rMSSD (root mean square of the successive differences) correlated with EEG features, including alpha power band in the left hemisphere and alpha band power asymmetry.

CONCLUSION

This study demonstrated five significant relationships between EEG and HRV features associated with stress. The ability to use stress-related EEG features in combination with correlated HRV features could help improve detecting stress and monitoring the progress of stress treatments/therapies. The outcomes of this study could enhance the efficiency of stress management technologies such as meditation studies and bio-feedback training.

Individual-Level Interventions for Decreasing Job-Related Stress and Enhancing Coping Strategies Among Nurses: A Systematic Review

Background: Nurses are facing unprecedented amounts of pressure because of the ongoing global health challenges. Improving nurses' resilience to job-related stress and enhancing their strategies to cope effectively with stressors are key issues facing many health care institutions during the COVID-19 pandemic. This literature review aimed to: a) provide a thorough overview of individual-level interventions for stress management among nurses, b) identify measurement tools utilized to evaluate nurses' stress level, and c) provide the best evidence-based recommendations for future research and practice adapted to the current restrictions. Design: Systematic review. Data Sources: Studies published between January 2000 and October 2020 were retrieved from the following sources: EBSCOhost, Dortmund University Library, PubMed, Medline, Google Scholar, Applied Nursing Research, and reference lists from relevant articles. Review methods: Individual-level interventions with a control group or a placebo intervention were included in the final sample. Primary outcome was defined as a change in individual stress level or stress symptoms which were measured by objective or subjective instruments with evidence of validity. Articles published in English or German were included in the present review. Results: In total, 27 relevant studies were included into the current review. There are some indications that technology-delivered interventions with relaxation and stress management interventions comprising cognitive-behavioral components might be effective in decreasing stress among nurses and improving their well-being. Furthermore, although there were some attempts to collect objectively measured parameters for assessing the primary outcome of stress, the majority of the interventions utilized self-reported stress scales. Conclusion: A wide range of interventions are available for nurses. However, it is of utmost importance to develop and implement stress management programs that are conveniently accessible in the workplace and above all, meet the current restrictions for minimizing human contacts. To this end, innovative interventions delivered through digital technology, such as virtual reality, seem to be a promising solution for combating the detrimental impact of stress on nurses. Special attention should be also paid to applying standardized objective measurement tools to allow the assessment of sensitive physiological indices and the generalizability of scientific knowledge.

Alpha frontal asymmetry underlies individual differences in reactivity to acute psychosocial stress in males

People vary in their responses to stress. The present study aimed to investigate whether and how alpha frontal asymmetry (AFA) measured in the resting state underlies the individual differences in psychological responses to acute psychosocial stress (e.g., increases in heart rate and cortisol) induced by the Trier social stress test. Forty-three healthy male adults were enrolled in this study. The results showed that the AFA score negatively predicted both heart rate and cortisol responses, that is relatively higher right-frontal activity during the resting state was related to a stronger physiological stress response. These results indicated that higher withdrawal motivation or effortful control is associated with a higher physiological stress response, which suggested that AFA in the resting state can serve as a biological predictor of acute stress responses in men.

Does non-invasive brain stimulation modulate emotional stress reactivity?

Excessive emotional responses to stressful events can detrimentally affect psychological functioning and mental health. Recent studies have provided evidence that non-invasive brain stimulation (NBS) targeting the prefrontal cortex (PFC) can affect the regulation of stress-related emotional responses. However, the reliability and effect sizes have not been systematically analyzed. In the present study, we reviewed and meta-analyzed the effects of repetitive transcranial magnetic (rTMS) and transcranial direct current stimulation (tDCS) over the PFC on acute emotional stress reactivity in healthy individuals. Forty sham-controlled single-session rTMS and tDCS studies were included. Separate random effects models were performed to estimate the mean effect sizes of emotional reactivity. Twelve rTMS studies together showed no evidence that rTMS over the PFC influenced emotional reactivity. Twenty-six anodal tDCS studies yielded a weak beneficial effect on stress-related emotional reactivity (Hedges’ g = −0.16, CI_95% = [−0.33, 0.00]). These findings suggest that a single session of NBS is insufficient to induce reliable, clinically significant effects but also provide preliminary evidence that specific NBS methods can affect emotional reactivity. This may motivate further research into augmenting the efficacy of NBS protocols on stress-related processes.

Frontal Electroencephalogram Alpha Asymmetry during Mental Stress Related to Workplace Noise

This study aims to investigate the effects of workplace noise on neural activity and alpha asymmetries of the prefrontal cortex (PFC) during mental stress conditions. Workplace noise exposure is a pervasive environmental pollutant and is negatively linked to cognitive effects and selective attention. Generally, the stress theory is assumed to underlie the impact of noise on health. Evidence for the impacts of workplace noise on mental stress is lacking. Fifteen healthy volunteer subjects performed the Montreal imaging stress task in quiet and noisy workplaces while their brain activity was recorded using electroencephalography. The salivary alpha-amylase (sAA) was measured before and immediately after each tested workplace to evaluate the stress level. The results showed a decrease in alpha rhythms, or an increase in cortical activity, of the PFC for all participants at the noisy workplace. Further analysis of alpha asymmetry revealed a greater significant relative right frontal activation of the noisy workplace group at electrode pairs F4-F3 but not F8-F7. Furthermore, a significant increase in sAA activity was observed in all participants at the noisy workplace, demonstrating the presence of stress. The findings provide critical information on the effects of workplace noise-related stress that might be neglected during mental stress evaluations.

The Relation Between Consumers' Frontal Alpha Asymmetry, Attitude, and Investment Decision

The frontal alpha asymmetry (FAA) is a neurophysiological measure of motivation and preference. Despite the FAA is associated to commercial pleasantness, conflicting evidence emerged in the literature regarding its relationship with behavior. To study the association between FAA and consumers' decision, we manipulated a commercial script to elicit diverse consumers' attitudes and decisions and to evaluate whether the FAA score is associated to their final investment. A little informative script (S1) was used to polarize consumers' attitudes and investments toward unfavorable scores, while a more personalized message (S2) to elicit in customers a favorable attitude and higher investments. Twenty-one participants listened to the scripts, and their FAA, attitude, and monetary investment were measured. In S1, the FAA did not correlate with neither attitude nor the investment decision, while a robust negative correlation between these variables was found in S2. No other peripheral body and neural measures associated with attitude or final decision. Our data suggest that the FAA correlates with attitude and decision, when a commercial script is customized and provides an adequate information, likely leading the consumer to a more reasoned and planned decision-making process. When facilitating a favorable attitude toward an offer, the negative correlation of FAA and behavior may reflect the involvement of a control system, whose role is to monitor and govern possible conflicts between approach and avoidance motivations. This observation provides additional indication on the value of FAA as a marker of consumer behaviors, and how it could be affected by experimental and contextual bias.

It is all relative: Contextual influences on boredom and neural correlates of regulatory processes

Interest in the influences on and strategies to mitigate boredom has grown immensely. Boredom emerges in contexts in which people have difficulty paying attention, such as underchallenging relative to optimally challenging conditions. The current study probed contextual influences on peoples' experience of boredom by manipulating the order with which people performed easy and optimally challenging conditions of a task (N = 113). We measured frontal alpha asymmetry (FAA) and theta/beta as neural correlates of self-regulatory and attentional control processes, respectively. Results showed self-reported boredom was higher in the easy condition when the optimal condition was completed before it. Similarly, participant's FAA shifted rightward from the first to the second task when the optimal condition was completed prior to the easy condition, indicating that self-regulatory processes were strongly engaged under these context-specific conditions. Theta/beta was lower during the easy relative to the optimal condition, regardless of the task order, indicating that maintaining attention in the easy condition was more difficult. No relations between perceptions of the task and neural correlates were observed. Exploratory analyses revealed higher levels of variability in FAA and theta/beta were associated with less enjoyment and more boredom, respectively. We speculate these observations reflect the less consistent engagement of self-regulatory and attentional control and, in turn, might play a role in peoples' subjective experience. We discuss the implications of our findings for our understanding of influences on and strategies to mitigate boredom, as well as how attentional and self-regulatory processes operate under conditions boredom typically emerges.