Dispositional traits help explain individual differences in relationships between a radiographic knee osteoarthritis measure, pain, and physical function

Background

The concordance between radiograph-derived Kellgren-Lawrence (KL) scores for knee osteoarthritis (KOA) and experimental and clinical pain and KOA-related physical function is conflicting.

Objectives

We investigate whether the inclusion of dispositional traits reduces variability between KOA radiographic findings, experimental pain, clinical pain, and function in individuals with knee pain.

Design

This study is a cross-sectional, secondary analysis of data collected from the UPLOAD-II study.

Methods

Adults aged 45-85 years with and without knee pain were enrolled. Data collected included sociodemographics, knee radiographs, experimental pain, clinical pain and function, and trait affect. Vulnerable and protective dispositional traits were classified from combined positive and negative trait affect measures. KL scores were determined from the knee radiographs. Unadjusted and adjusted (age, sex, comorbidities, and body mass index) regression analyses were completed with SAS version 9.4 (Cary, NC, USA).

Results

The study included 218 individuals with a mean age of 58 years, 63.6% women, and 48.2% non-Hispanic black adults. Dispositional traits were associated with the experimental pain measures. No association between radiographic KOA and experimental pain was observed. In a combined and adjusted analysis, dispositional traits were predictive of knee punctate pain temporal summation (p = 0.0382). Both dispositional traits and radiographic KOA scores independently and combined were predictive of Graded Chronic Pain Scale pain and function, and Western Ontario and McMaster University pain and function (ps ⩽ 0.01). Improvements in R2 were noted across all models with the inclusion of dispositional traits.

Conclusion

Consideration of dispositional traits reduces the variability between radiographic KOA and pain and function. Non-pathological and associated pain-related psychological factors and dispositional traits might serve as parsimonious proxy tools to improve clinical assessments.

Registration

N/A.

Predictors of professional burnout and fulfilment in a longitudinal analysis on nurses and healthcare workers in the COVID-19 pandemic

AIMS AND OBJECTIVES

(1) To investigate the vulnerability of nurses to experiencing professional burnout and low fulfilment across 5 months of the COVID-19 pandemic. (2) To identify modifiable variables in hospital leadership and individual vulnerabilities that may mitigate these effects.

BACKGROUND

Nurses were at increased risk for burnout and low fulfilment prior to the COVID-19 pandemic. Hospital leadership factors such as organisational structure and open communication and consideration of employee opinions are known to have positive impacts on work attitudes. Personal risk factors for burnout include symptoms of depression and anxiety.

METHODS

Healthcare workers (n = 406 at baseline, n = 234 longitudinal), including doctors (n = 102), nurses (n = 94), technicians (n = 90) and non-clinical administrative staff (n = 120), completed 5 online questionnaires, once per month, for 5 months. Participants completed self-report questionnaires on professional fulfilment and burnout, perceptions of healthcare leadership, and symptoms of anxiety and depression. Participants were recruited from various healthcare settings in the southeastern United States. The STROBE checklist was used to report the present study.

RESULTS

Both at baseline and across the 5 months, nurses working during the COVID-19 pandemic reported increased burnout and decreased fulfilment relative to doctors. For all participants, burnout remained largely steady and fulfilment decreased slightly. The strongest predictors of both burnout and fulfilment were organisational structure and depressive symptoms. Leadership consideration and anxiety symptoms had smaller, yet significant, relationships to burnout and fulfilment in longitudinal analyses.

CONCLUSIONS

Burnout and reduced fulfilment remain a problem for healthcare workers, especially nurses. Leadership styles and employee symptoms of depression and anxiety are appropriate targets for intervention.

RELEVANCE TO CLINICAL PRACTICE

Leadership wishing to reduce burnout and increase fulfilment among employees should increase levels of organisational support and consideration and expand supports to employees seeking treatment for depression and anxiety.

Delayed ocular disengagement from arousing scenes

Visual exploration of the world is supported by eye movements which can be speeded up or delayed depending on bottom-up stimulation, top-down goals, and prior associations. Previous studies observed faster initiation of saccades toward emotional than neutral natural scenes; however, less is known concerning saccades which originate from emotional, compared with neutral, scenes. Here, we addressed this issue by examining a task in which participants continuously moved their gaze from and toward pictures (natural scenes), which could be emotional or neutral, and changed position in every trial. Saccades were initiated later when the starting picture was emotional compared to neutral, and this slowing was associated with the arousal value of the picture, suggesting that ocular disengagement does not vary with stimulus valence but is affected by engaging picture contents such as erotica and threat/injuries.

Protective and risk factors associated with substance use coping among healthcare workers during the COVID-19 pandemic

Background

Healthcare workers (HCWs) experienced high levels of stress and mental health consequences associated with the COVID-19 pandemic, which may have contributed to unhealthy coping behaviors, such as substance use coping (SUC). This study aimed to understand the extent of and predictors of SUC.

Methods

The sample consisted of 263 HCWs in North Central Florida. Univariable and multivariable logistic regression analyses investigated whether moral injury and other work risk factors, protective factors, and clinically relevant symptoms (i.e., work exhaustion, interpersonal disengagement, depression, anxiety, and/or PTSD) were associated with likelihood of SUC.

Results

Clinically relevant levels of interpersonal disengagement and anxiety increased the likelihood of SUC. Mediational analyses found that interpersonal disengagement and anxiety explained 54.3% of the relationship between Self Moral Injury and SUC and explained 80.4% of the relationship between professional fulfillment and SUC.

Conclusion

Healthcare supervisors should be aware that providers who are experiencing moral injury and less professional fulfillment may be experiencing significant interpersonal disengagement and anxiety, which could lead to SUC. Future studies should examine the effects of implementing targeted prevention and treatment interventions, along with longitudinal outcomes related to SUC behaviors.

Imagery, emotion, and bioinformational theory: From body to brain

The bioinformational theory of emotional imagery is a model of the hypothetical mental representations activated when people imagine emotionally engaging events, and was initially proposed to guide research and practice in the use of imaginal exposure as a treatment for fear and anxiety (Lang, 1979). In this 50 year overview, we discuss the development of bioinformational theory and its impact on the study of psychophysiology and psychopathology, most importantly assessing its viability and predictions in light of more recent brain-based studies of neural functional activation. Bioinformational theory proposes that narrative imagery, typically cued by language scripts, activates an associative memory network in the brain that includes stimulus (e.g., agents, contexts), semantic (e.g., facts and beliefs) and, most critically for emotion, response information (e.g., autonomic and somatic) that represents relevant real-world coping actions and reactions. Psychophysiological studies in healthy and clinical samples reliably find measurable response output during aversive and appetitive narrative imagery. Neuroimaging studies confirm that emotional imagery is associated with significant activation in motor regions of the brain, as well as in regions implicated in episodic and semantic memory retrieval, supporting the bioinformational view that narrative imagery prompts mental simulation of events that critically includes the actions and reactions engaged in emotional contexts.

Dimensional distress and orbitofrontal thickness in anxiety patients

Thickness of the medial orbitofrontal cortex (mOFC) was assessed as it varied with reported symptoms of anxiety and depression in a large sample of anxiety patients. A principal component analysis identified a primary factor of transdiagnostic dimensional distress that predicted 24% of the mOFC variance. Severity of distress symptomology was associated with thinning of the mOFC in both hemispheres for both men and women, regardless of the primary DSM diagnosis. Taken together, the data indicate that mOFC thickness might be useful as an objective measure of disorder severity as well as to assess pharmacological or psychological treatment outcome.

Effects of COVID-19 stress, proximity, and adverse childhood experiences on healthcare workers' mental health

Past research has shown that healthcare workers (HCWs) experience high levels of psychological distress during epidemics and pandemics, resulting in cascading effects that have led to chronically understaffed hospitals and healthcare centers. Due to the nature of their responsibilities and workplace stress, HCWs are among vulnerable groups especially during global health crises. During COVID-19 many healthcare workers reported greater symptoms of anxiety, depression, and COVID-19 related worries. Furthermore, adverse childhood experiences increase vulnerability for psychological conditions, especially during pandemics. This study sets out to (1) investigate the moderating effects of adverse childhood experiences on healthcare workers' COVID-19 related stressors and depression/anxiety symptoms, and (2) investigate the moderating effects of adverse childhood experiences on proximity to the COVID-19 virus and depression/anxiety symptoms. Participants included 438 employed HCWs recruited from academic medical centers and smaller healthcare agencies in northcentral Florida between October to December 2020. Mean age of participants was 38.23 (SD = 11.5) with most of the HCWs being white (72.1%), non-Hispanic (86.8%) and female (82%). Healthcare workers completed several online questionnaires, including the Adverse Childhood Experiences scale, Patient Health Questionnaire, Generalized Anxiety Disorder Scale, a COVID-19 specific worries scale, and a Social Proximity to COVID-19 scale. Healthcare workers experiencing specific COVID-19 worries reported experiencing anxiety and depressive symptoms. A significant positive interaction was seen between childhood adverse experiences globally and COVID-19 worries on anxiety symptoms. A significant positive interaction was observed between childhood maltreatment specifically and COVID-19 worries on depressive symptoms. Additionally, a positive interaction effect was seen between childhood adverse experiences and COVID-19 social proximity for both depression symptoms and anxiety symptoms. Findings from the present study indicate that adverse childhood experiences strengthen the relationship between COVID-19 worry/proximity and negative psychological symptoms. Vulnerable populations such as individuals who have experienced ACEs could benefit from targeted and specific interventions to cope with the collective trauma experienced globally due to COVID-19. As COVID-19 becomes endemic, hospital leadership and authorities should continue addressing COVID-19 worries and HCWs' psychological symptoms through mental health support and organizational interventions.

Resilient, but for how long? The relationships between temperament, burnout, and mental health in healthcare workers during the Covid-19 pandemic

Introduction

Dispositional traits of wellbeing and stress-reaction are strong predictors of mood symptoms following stressful life events, and the COVID-19 pandemic introduced many life stressors, especially for healthcare workers.

Methods

We longitudinally investigated the relationships among positive and negative temperament group status (created according to wellbeing and stress-reaction personality measures), burnout (exhaustion, interpersonal disengagement), COVID concern (e.g., health, money worries), and moral injury (personal acts, others' acts) as predictors of generalized anxiety, depression, and post-traumatic stress symptoms in 435 healthcare workers. Participants were employees in healthcare settings in North Central Florida who completed online surveys monthly for 8 months starting in October/November 2020. Multidimensional Personality Questionnaire subscale scores for stress-reaction and wellbeing were subjected to K-means cluster analyses that identified two groups of individuals, those with high stress-reaction and low wellbeing (negative temperament) and those with the opposite pattern defined as positive temperament (low stress-reaction and high wellbeing). Repeated measures ANOVAs assessed all time points and ANCOVAs assessed the biggest change at timepoint 2 while controlling for baseline symptoms.

Results and Discussion

The negative temperament group reported greater mood symptoms, burnout, and COVID concern, than positive temperament participants overall, and negative participants' scores decreased over time while positive participants' scores increased over time. Burnout appeared to most strongly mediate this group-by-time interaction, with the burnout exhaustion scale driving anxiety and depression symptoms. PTSD symptoms were also related to COVID-19 health worry and negative temperament. Overall, results suggest that individuals with higher stress-reactions and more negative outlooks on life were at risk for anxiety, depression, and PTSD early in the COVID-19 pandemic, whereas individuals with positive temperament traits became more exhausted and thus more symptomatic over time. Targeting interventions to reduce mood symptoms in negative temperament individuals and prevent burnout/exhaustion in positive temperament individuals early in an extended crisis may be an efficient and effective approach to reduce the mental health burden on essential workers.

Electrophysiological normative responses to emotional, neutral, and cigarette-related images

To create reproducible emotional probes, affective scientists rely on sets of standardized pictures that are normed using subjective ratings of valence and emotional arousal. However, when emotional responses are investigated using neurophysiological measures, it might be more appropriate to select pictures integrating information from normative subjective reports and normative neurophysiological responses. Here, we provide electrophysiological normative responses for 323 emotional pictures (215 from the IAPS) covering a wide range of categories (erotica, romantic, appetizing foods, landscapes, people engaged in mundane activities, household objects, disgusting objects, accidents, sad people, violence, mutilations, and cigarette-related contents). Event-related potentials (ERPs) and subjective ratings of pleasure and emotional arousal were collected from 763 individuals (52% females, 41% white) aged between 18 and 65 (mean = 43). For each image, the mean amplitude of the late positive potential (LPP, an electrophysiological index of motivational relevance) and the mean subjective ratings of valence and arousal were calculated. We validated our procedure by showing that the subjective ratings of valence and arousal from this sample were highly correlated to the IAPS' published norms (Pearson r = .97 for pleasure and r = .82 for emotional arousal). LPP responses and subjective ratings of emotional arousal also were correlated (Pearson r = .61), but some categories reported being significantly more arousing than neutral (i.e., food, landscapes, and unpleasant objects) did not evoke LPPs significantly different from those evoked by neutral pictures. Researchers interested in probing the brain's affective systems can use these electrophysiological normative responses to create emotional probes that evoke reliable neuroaffective responses.

Hippocampal and amygdala volumes vary with transdiagnostic psychopathological dimensions of distress, anxious arousal, and trauma

Reduced hippocampal and/or amygdala volumes have been reported in patients with a variety of different anxiety diagnoses, suggesting that structural alterations may vary transdiagnostically across the internalizing disorders. The current study measured hippocampal and amygdala volumes in anxiety and mood disorder patients assessing differences that vary dimensionally with transdiagnostic factors of distress, anxious arousal, and trauma, based on a principal components analysis of questionnaires relating to symptomology. High-resolution structural images were collected in a sample of 165 patients, and volumes extracted from the hippocampal formation (including CA1, CA2/3, CA4/DG, subiculum, and molecular layer) and the amygdala. Transdiagnostically, increasing distress was associated with reduced hippocampal CA1 volume, increasing anxious arousal was associated with reduced hippocampal CA4/DG volume, and increasing trauma severity was associated with reduced amygdala volume in women. Taken together, the data indicate that subcortical brain volumes decrease as the severity of transdiagnostic psychopathological symptomology increases.

Vulnerable Dispositional Traits and Chronic Pain: Predisposing but not Predetermining

Dispositional traits can be protective or contribute to increased vulnerability in individuals with chronic pain. This study aims to evaluate the association between two dispositional trait measures, affect balance style and multi-domain trait groups, with psychosocial measures, clinical pain, functional pain, and experimental pain at two years in individuals with chronic knee pain. The study is a prospective analysis of 168 community dwelling individuals aged 45 to 85 years old with knee pain with or at risk for knee osteoarthritis. At baseline, affect balance style and multi-domain trait groups were associated with psychosocial measures, clinical pain, and functional status. At the two-year time point, the multi-domain trait groups were associated with the clinical pain measures. Interestingly, individuals with previously demonstrated vulnerable traits showed more variability in dispositional trait status at the two-year time point compared to those with dispositional traits previously demonstrated as more protective. Findings reiterate that dispositional traits are predisposing but are not predetermining regarding pain-related experiences. PERSPECTIVE: Vulnerable and protective dispositional traits are positively and negatively associated with clinical pain and functional limitations respectively. Although considered relatively stable, a 30-50% shift in dispositional traits was indicated over a two-year period. Findings highlight that dispositional trait are modifiable and thus, predisposing but not predetermining for persisting chronic pain.

fMRI replicability during emotional scene viewing: Functional regions and sample size

Recent findings have questioned the replicability of functional magnetic resonance imaging (fMRI) in the study of affective processing, reporting low replicability of emotional enhancement during a face-matching task. However, poor replicability may instead reflect a lack of emotional engagement for face matching. In the current study, replicability of emotional enhancement was tested in a large (N = 160) sample when emotional engagement was assessed during pleasant, neutral, and unpleasant picture viewing, which reliably engages affective reactions in both the brain and the body. Replicability was computed using a subsampling technique, in which random sets of subjects of different sample sizes (N = 20, 40, 60, 80) were selected from the entire dataset, and replicability of emotional enhancement for peaks, clusters, and voxels were averaged across 500 permutations for each sample size. Consistent with previous findings, fMRI replicability increased with increasing sample size. On the other hand, even with relatively small samples, fMRI replicability for peaks, clusters, and voxels during emotional, compared to neutral, scene viewing was good to excellent. Importantly, replicability varied in different brain regions, with excellent replicability at both the cluster and peak level with an N of 40, at the most conservative threshold (p < .001), in the amygdala and the visual cortex. The data argue against general recommendations regarding sample size in fMRI studies of emotion, suggesting instead that degree of replicability depends on successful emotional engagement in task-related brain regions.

Narrative imagery: Emotional modulation in the default mode network

The default mode network (DMN) is activated when constructing and imagining narrative events, with functional brain activity in the medial-prefrontal cortex hypothesized to be modulated during emotional processing by adding value (or pleasure) to the episodic representation. However, since enhanced reactivity during emotional, compared to neutral, content is a more frequent finding in both the brain and body in physiological, neural, and behavioral measures, the current study directly assesses the effects of pleasure and emotion during narrative imagery in the DMN by using a within-subject design to first identify the DMN during resting state and then assess activation during pleasant, neutral, or unpleasant imagery. Replicating previous findings, enhanced functional activity in the medial prefrontal cortex was found when imagining pleasant, compared to unpleasant, events. On the other hand, emotion-related activation was found when imagining either pleasant or unpleasant, compared to neutral, events in other nodes of the DMN including the posterior cingulate cortex (PCC), angular gyrus, anterior hippocampus, lateral temporal cortex, temporal pole, dorsomedial prefrontal cortex (dmPFC), and ventrolateral prefrontal cortex (vlPFC). Pervasive emotional modulation in the DMN is consistent with the view that a primary function of event retrieval and construction is to remember, recreate, and imagine motivationally relevant events important for planning adaptive behavior.

Sex differences in the aging brain? A voxel-based morphometry analysis of the hippocampus and the amygdala

OBJECTIVES

Volumetric reductions in the hippocampus and the amygdala are considered a hallmark for many psychiatric and neurodegenerative disorders. Because brain atrophy is often observed in disorders that have a higher prevalence in females than males, it has been proposed that sex differences in the aging brain represent a vulnerability factor for developing more severe psychiatric conditions.

METHODS

Sexual dimorphism was assessed in the amygdala volume and hippocampal volume in a large sample (N = 554) of healthy individuals ranging from 20 to 79 years old, using structural brain data available from a public dataset.

RESULTS

In both the hippocampus and the amygdala, a quadratic association was found between age and brain volume. Using uncorrected data for head size [total intracranial volume (TIV)], males clearly demonstrated larger amygdala and hippocampal volume across all ages, and an interaction between age and sex in the hippocampus supported the hypothesis of accelerated atrophy in the hippocampus in later life (60-79 years old). However, when volumetric data adjusted for TIV were used, sex differences were not observed in the hippocampus nor the amygdala.

CONCLUSION

These findings support the extensive series of studies suggesting that sex differences in brain volume are likely related to the confounding effect of head size. While continued effort is allocated to identify sex-related biomarkers, increasing evidence suggests that sexual dimorphism in the hippocampus or the amygdala does not appear to be the primary candidates for precision medicine to identify sex-related biomarkers that index potential vulnerabilities.

Trauma-related dysfunction in the fronto-striatal reward circuit

INTRODUCTION

Reduced reactivity to pleasurable stimulation is a defining symptom of post-traumatic stress disorder (PTSD), but trauma exposure also increases the severity of many anxiety and mood disorders, including depression, social anxiety, and panic disorder, suggesting that reward system dysfunction might be pervasive in the internalizing disorders. The ventromedial prefrontal cortex (vmPFC) and ventral striatum are core components of the reward circuit and the current study assesses functional activity and connectivity in this circuit during emotional picture viewing in anxiety and mood disorder patients.

METHOD

Functional brain activity (fMRI) and functional connectivity in the fronto-striatal circuit were measured in a large sample of patients diagnosed with anxiety and mood disorders (n=155) during affective scene viewing as it varied with trauma exposure and temperament.

RESULTS

In women, but not men, blunted fronto-striatal connectivity was associated with increased posttraumatic anhedonic symptoms, whereas the amplitude of functional activity was not related to trauma exposure. In both men and women, reduced fronto-striatal connectivity was associated with decreases in temperamental positive affect. When predicting fronto-striatal connectivity, temperament and posttraumatic symptomology accounted for independent proportions of variance.

LIMITATIONS

In this civilian sample of anxiety disorder patients, men reported very little trauma-related symptomology.

CONCLUSIONS

Because dysfunctional reward processing due to trauma and temperament is pervasive across the internalizing disorder spectrum, assessing the integrity of the fronto-striatal reward circuit could provide important information in diagnostic and treatment protocols.

Assessing the role of the amygdala in fear of pain: Neural activation under threat of shock

INTRODUCTION

The DSM-5 explicitly states that the neural system model of specific phobia is centered on the amygdala. However, this hypothesis is predominantly supported by human studies on animal phobia, whereas visual cuing of other specific phobias, such as dental fear, do not consistently show amygdala activation. Considering that fear of anticipated pain is one of the best predictors of dental phobia, the current study investigated neural and autonomic activity of pain anticipation in individuals varying in the degree of fear of dental pain.

METHOD

Functional brain activity (fMRI) was measured in women (n = 31) selected to vary in the degree of self-reported fear of dental pain when under the threat of shock, in which one color signaled the possibility of receiving a painful electric shock and another color signaled safety.

RESULTS

Enhanced functional activity during threat, compared to safety, was found in regions including anterior insula and anterior/mid cingulate cortex. Importantly, threat reactivity in the anterior insula increased as reported fear of pain increased and further predicted skin conductance changes during pain anticipation.

LIMITATIONS

The sample was comprised of women.

CONCLUSIONS

Individual differences in fear of pain vary with activation in the anterior insula, rather than with the amygdala, indicating that fear is not uniquely associated with amygdala activation. Whereas coping techniques such as emotion regulation have been found to vary with activation in a frontal-amygdala circuit when confronted with visual cues, precision psychiatry may need to target specific brain circuits to diagnose and treat different types of specific phobia.

Aversive perception in a threat context: Separate and independent neural activation

Unpleasant, compared to neutral, scenes reliably prompt enhanced functional brain activity in the amygdala and inferotemporal cortex. Considering data from psychophysiological studies in which defensive reactivity is further enhanced when viewing unpleasant scenes under threat of shock (compared to safety), the current study investigates functional activation in the amygdala-inferotemporal circuit when unpleasant (or neutral) scenes are viewed under threat of shock or safety. In this paradigm, a cue signaling threat or safety was presented in conjunction with either an unpleasant or neutral picture. Replicating previous studies, unpleasant, compared to neutral, scenes reliably enhanced activation in the amygdala and inferotemporal cortex. Functional activity in these regions, however, did not differ whether scenes were presented in a context threatening shock exposure, compared to safety, which instead activated regions of the anterior insula and cingulate cortex. Taken together, the data support a view in which neural regions activated in different defensive situations act independently.

Common circuit or paradigm shift? The functional brain in emotional scene perception and emotional imagery

Meta-analytic and experimental studies investigating the neural basis of emotion often compare functional activation in different emotional induction contexts, assessing evidence for a "core affect" or "salience" network. Meta-analyses necessarily aggregate effects across diverse paradigms and different samples, which ignore potential neural differences specific to the method of affect induction. Data from repeated measures designs are few, reporting contradictory results with a small N. In the current study, functional brain activity is assessed in a large (N = 61) group of healthy participants during two common emotion inductions-scene perception and narrative imagery-to evaluate cross-paradigm consistency. Results indicate that limbic and paralimbic regions, together with visual and parietal cortex, are reliably engaged during emotional scene perception. For emotional imagery, in contrast, enhanced functional activity is found in several cerebellar regions, hippocampus, caudate, and dorsomedial prefrontal cortex, consistent with the conception that imagery is an action disposition. Taken together, the data suggest that a common emotion network is not engaged across paradigms, but that the specific neural regions activated during emotional processing can vary significantly with the context of the emotional induction.

Attentional capture by simultaneous pleasant and unpleasant emotional distractors

Both high-arousal pleasant and unpleasant task-irrelevant stimuli capture attention and divert processing away from the main task leading to impaired behavioral performance in concurrent tasks. Most studies have separately investigated interference effects of unpleasant and pleasant stimuli on behavior. Thus, little is known about how pleasant and unpleasant task-irrelevant stimuli influence behavior simultaneously. In the present study, we investigated this question during a visual-letter search task. We tested two alternative hypotheses about the influence of simultaneous pleasant and unpleasant task-irrelevant stimuli on task performance. If behavior is purely determined by the intensity of the distractor stimuli (independent of valence), then we would expect the interference effect of simultaneous pleasant and unpleasant distractors to be similar to the influence of two pleasant or two unpleasant distractor stimuli. In contrast, because of opponent interactions between appetitive and aversive motivational systems, the interference effect of simultaneous pleasant and unpleasant stimuli might be weakened. We found that the interference effect of a compound pleasant-plus-unpleasant stimulus was greater than that of a neutral-plus-emotional stimulus and similar to that of two pleasant or two unpleasant stimuli. These results suggest that at the level of behavior, the influence of joint pleasant and unpleasant task-irrelevant stimuli during perception is mainly determined by the intensity of the stimuli, and independent of their valence. (PsycINFO Database Record (c) 2018 APA, all rights reserved).