Processing Of Negative Emotional Stimuli Research Articles

Emotional processing and positive affect after acute exercise in healthy older adults.

The well-elucidated improvement of mood immediately after exercise in older adults presumably involves adaptations in emotion-processing brain networks. However, little is known about effects of acute exercise on appetitive and aversive emotion-related network recruitment in older adults. The purpose of this study was to determine the effect of acute exercise, compared to a seated rest control condition, on pleasant and unpleasant emotion-related regional activation in healthy older adults. Functional MRI data were acquired from 32 active older adults during blocked presentations of pleasant, neutral and unpleasant images from the International Affective Pictures System. fMRI data were collected after participants completed 30 min of moderate to vigorous intensity cycling or seated rest, performed in a counterbalanced order across separate days in a within-subject design. The findings suggest three ways that emotional processing in the brain may be different immediately after exercise (relative to immediately after rest): First, reduced demands on emotional regulation during pleasant emotional processing as indicated by lower precuneus activation for pleasant stimuli; second, reduced processing of negative emotional stimuli in visual association areas as indicated by lower activation for unpleasant stimuli in the bilateral fusiform and ITG; third, an increased recruitment in activation associated with regulating/inhibiting unpleasant emotional processing in the bilateral medial superior frontal gyrus (dorsomedial prefrontal cortex), angular gyri, supramarginal gyri, left cerebellar crus I/II and a portion of right dorsolateral prefrontal cortex. Overall, these findings support that acute exercise in active older adults alters activation in key emotional processing and regulating brain regions.

The Predictive Role of the Posterior Cerebellum in the Processing of Dynamic Emotions.

Recent studies have bolstered the important role of the cerebellum in high-level socio-affective functions. In particular, neuroscientific evidence shows that the posterior cerebellum is involved in social cognition and emotion processing, presumably through its involvement in temporal processing and in predicting the outcomes of social sequences. We used cerebellar transcranial random noise stimulation (ctRNS) targeting the posterior cerebellum to affect the performance of 32 healthy participants during an emotion discrimination task, including both static and dynamic facial expressions (i.e., transitioning from a static neutral image to a happy/sad emotion). ctRNS, compared to the sham condition, significantly reduced the participants' accuracy to discriminate static sad facial expressions, but it increased participants' accuracy to discriminate dynamic sad facial expressions. No effects emerged with happy faces. These findings may suggest the existence of two different circuits in the posterior cerebellum for the processing of negative emotional stimuli: a first-time-independent mechanism which can be selectively disrupted by ctRNS, and a second time-dependent mechanism of predictive "sequence detection"which can be selectively enhanced by ctRNS. This latter mechanism might be included among the cerebellar operational models constantly engaged in the rapid adjustment of social predictions based on dynamic behavioral information inherent to others' actions. We speculate that it might be one of the basic principles underlying the understanding of other individuals' social and emotional behaviors during interactions.

Subcortical contributions to salience network functioning during negative emotional processing

Core regions of the salience network (SN), including the anterior insula (aINS) and dorsal anterior cingulate cortex (dACC), coordinate rapid adaptive changes in attentional and autonomic processes in response to negative emotional events. In doing so, the SN incorporates bottom-up signals from subcortical brain regions, such as the amygdala and periaqueductal gray (PAG). However, the precise influence of these subcortical regions is not well understood. Using ultra-high field 7-Tesla functional magnetic resonance imaging, this study investigated the bottom-up interactions of the amygdala and PAG with the SN during negative emotional salience processing. Thirty-seven healthy participants completed an emotional oddball paradigm designed to elicit a salient negative emotional response via the presentation of random, task-irrelevant negative emotional images. Negative emotional processing was associated with prominent activation in the SN, spanning the amygdala, PAG, aINS, and dACC. Consistent with previous research, analysis using dynamic causal modelling revealed an excitatory influence from the amygdala to the aINS, dACC, and PAG. In contrast, the PAG showed an inhibitory influence on amygdala, aINS and dACC activity. Our findings suggest that the amygdala may amplify the processing of negative emotional stimuli in the SN to enable upstream access to attentional resources. In comparison, the inhibitory influence of the PAG possibly reflects its involvement in modulating sympathetic-parasympathetic autonomic arousal mediated by the SN. This PAG-mediated effect may be driven by amygdala input and facilitate bottom-up processing of negative emotional stimuli. Overall, our results show that the amygdala and PAG modulate divergent functions of the SN during negative emotional processing.

Adolescent Substance Use Is Associated With Altered Brain Response During Processing of Negative Emotional Stimuli.

Substance misuse is often associated with emotional dysregulation. Understanding the neurobiology of emotional responsivity and regulation as it relates to substance use in adolescence may be beneficial for preventing future use. The present study used a community sample, ages 11-21 years old (N = 130, Mage = 17), to investigate the effects of alcohol and marijuana use on emotional reactivity and regulation using an Emotional Go-NoGo task during functional magnetic resonance imaging. The task consisted of three conditions, where target (Go) stimuli were either happy, scared, or calm faces. Self-report lifetime (and past-90-day) drinking and marijuana use days were provided at all visits. Substance use was not differentially related to task performance based on condition. Whole-brain linear mixed-effects analyses (controlling for age and sex) found that more lifetime drinking occasions was associated with greater neural emotional processing (Go trials) in the right middle cingulate cortex during scared versus calm conditions. In addition, more marijuana use occasions were associated with less neural emotional processing during scared versus calm conditions in the right middle cingulate cortex and right middle and inferior frontal gyri. Substance use was not associated with brain activation during inhibition (NoGo trials). These findings demonstrate that substance use-related alterations in brain circuitry are important for attention allocation and the integration of emotional processing and motor response when viewing negative emotional stimuli.

Neuronal response to high negative affective stimuli in major depressive disorder: An fMRI study

BackgroundDisturbed emotion processing underlies depression. We examined the neuronal underpinnings of emotional processing in patients (PAT) with major depressive disorder (MDD) compared to healthy volunteers (HV) using functional magnetic resonance (fMRI) scan. MethodsThirty-six MDD patients and 30 HV underwent T2-weighted fMRI assessments during the presentation of an implicit affective processing task in three conditions. They differed regarding their affective quality (=valence, high negative, low negative and neutral stimuli) and regarding the arousal based on stimuli from the International Affective Picture System. ResultsGroup contrasts showed lower left-sided activation in dorsolateral prefrontal cortex (DLPFC), anterior PFC, precentral and premotor cortex in PAT compared with HV (Cluster-level threshold, 5000 iterations, p<0.01). We found a significant interaction effect of valence and group, a significant effect of emotional valence and a significant effect of group. All effects were shown in brain regions within the emotional network (Cluster-level threshold, 5000 iterations, p<0.01). Higher arousal (rho=-0.33, p<0.01) and higher valence (rho=-0.33, p<0.01) during high negative stimuli presentation as well as more severe depression (Beck Depression Inventory II [BDI II]; r = 0.39, p = 0.01) were significantly negatively associated with left DLFPC activity in patients. LimitationsPotential influence of psychopharmacological drugs on functional activation is one of the most discussed source of bias in studies with medicated psychiatric patients. ConclusionsThe results highlight the importance of left DLPFC during the processing of negative emotional stimuli in MDD. The integration of a neurophysiological model of emotional processing in MDD may help to clarify and improve therapeutic options.

Brain functional effects of electroconvulsive therapy during emotional processing in major depressive disorder

BackgroundIn treatment-resistant major depressive disorder (MDD), electroconvulsive therapy (ECT) is a treatment with high efficacy. While knowledge regarding changes in brain structure following ECT is growing, the effects of ECT on brain function during emotional processing are largely unknown. ObjectiveWe investigated the effects of ECT on the activity of the anterior cingulate cortex (ACC) and amygdala during negative emotional stimuli processing and its association with clinical response. MethodsIn this non-randomized longitudinal study, patients with MDD (n = 37) were assessed before and after treatment with ECT. Healthy controls (n = 37) were matched regarding age and gender. Functional magnetic resonance imaging (fMRI) was obtained twice, at baseline and after six weeks using a supraliminal face-matching paradigm. In order to evaluate effects of clinical response, additional post-hoc analyses were performed comparing responders to non-responders. ResultsAfter ECT, patients with MDD showed a statistically significant increase in ACC activity during processing of negative emotional stimuli (pFWE = .039). This effect was driven by responders (pFWE = .023), while non-responders showed no increase. Responders also had lower pre-treatment ACC activity compared to non-responders (pFWE = .025). No significant effects in the amygdala could be observed. ConclusionsECT leads to brain functional changes in the ACC, a relevant region for emotional regulation during processing of negative stimuli. Furthermore, baseline ACC activity might serve as a biomarker for treatment response. Findings are in accordance with recent studies highlighting properties of pre-treatment ACC to be associated with general antidepressive treatment response.

Callous-unemotional traits and the attentional bias towards emotional stimuli: Testing the moderating role of emotional and behavioural problems among high-risk adolescents.

Former studies demonstrated that antisocial youth with callous-unemotional (CU) traits are impaired in the processing of negative emotional stimuli. The aim of the current study was to explore the moderating role of different behavioural (i.e. conduct problems, hyperactivity-inattention) and emotional problems (i.e. internalizing symptoms) in the relationship between CU traits and attentional bias towards emotional stimuli. Besides using self-report measures, attentional bias was tested by an affective dot-probe task in a high-risk sample of 102 adolescent boys (M age = 16.34 years; SD = 1.32). CU traits were related to reduced attention to emotionally distressing pictures. Furthermore, conduct problems significantly moderated the relationship between CU traits and attention to distress cues. These findings highlight the importance of considering potential moderators to the well-established link between CU traits and deficits in response to negative emotional cues.

Transcranial magnetic stimulation combined with duloxetine improves attentional negativity bias in patients with depression: pilot study for a future trial

Background and objective: Patients with depression often have cognitive deficits in perception, attention, executive control, and decision-making. Attentional negativity bias is a prominent symptom of depression. Indeed, during processing of negative emotional stimuli, the bilateral amygdala is over-activated, while prefrontal cortical activity decreases from baseline in patients with depression. Previous studies have reported that transcranial magnetic stimulation (TMS) can increase synaptic excitability. In this study, we investigate the effects of TMS combined with duloxetine versus duloxetine alone on attentional negativity bias in patients with depression. Subjects and Methods: A multi-center, randomized, double-blind, sham-stimulation, parallel-control trial will be conducted in Beijing Anding Hospital of Capital Medical University, Beijing, China. In the trial, 406 patients with depression will be included and will be randomly divided into a study group and a control group (n = 203 patients per group). Patients in both groups will receive oral administration of 60 mg/d duloxetine for 6 successive weeks, while patients in the study and control groups will undergo simultaneous TMS or sham-stimulation, respectively. The latter interventions will be performed once daily, five times a week with a 2 day interval between the first five and the last five procedures (10 times in total). This study was approved by Hospital Ethics Committee, Beijing Anding Hospital of Capital Medical University, China (approval No. 2017-79-2017111-2) on December 20, 2017. Protocol version: 3.0. Outcome measures: The primary outcome measure is effectiveness rate of the Hamilton Rating Scale for Depression–17-Item (HAMD17) after 6 weeks of treatment. The secondary outcome measures are: complete remission rate after 6 weeks of treatment; effectiveness rate after 1, 2, and 4 weeks of treatment; changes in HAMD17, Athens Insomnia Scale, Digit Symbol Substitution Test, 16-Item Quick Inventory of Depressive Symptomatology Self-Report Scale, 7-Item Generalized Anxiety Disorder Scale, Sheehan Disability Scale, Perceived Deficits Questionnaire-Depression, Arizona Sexual Experience Scale, and Mini-International Neuropsychiatric Interview suicide scores after 1, 2, 4, and 6 weeks of treatment relative to baseline; electroencephalogram results after 2 and 6 weeks of treatment; and safety indicators and adverse events after 6 weeks of treatment. Discussion: We plan to perform a study to provide preliminary evidence for the use of TMS combined with duloxetine to improve the attentional negativity bias in patients with depression. Trial registration: This study was registered with the Chinese Clinical Trial Registry (registration number: ChiCTR-INR-17014075) on December 21, 2017.

Does Meditation Alter Brain Responses to Negative Stimuli? A Systematic Review.

Background: Despite several attempts to review and explain how meditation alters the brain and facilitates emotion regulation, the extent to which meditation and emotion regulation strategies share the same neural mechanisms remains unclear.Objective: We aim to understand the influence of meditation on the neural processing of negative emotional stimuli in participants who underwent meditation interventions (naive meditators) and long-term meditators.Methodology: A systematic review was conducted using standardized search operators that included the presence of terms related to emotion, meditation and neuro-imaging techniques in PsycInfo, PubMed, Scopus, and Web of Science databases.Results: Searches identified 882 papers, of which 11 were eligible for inclusion. Results showed a predominance of greater prefrontal/frontal activity related to meditation, which might indicate the increased recruitment of cognitive/attentional control resources in naïve and long-term meditators. This increased frontal activity was also observed when participants were asked to simply react to negative stimuli. Findings from emotion-related areas were scarce but suggested increased insular activity in meditators, potentially indicating that meditation might be associated with greater bodily awareness.Conclusions: Meditation practice prompts regulatory mechanisms when participants face aversive stimuli, even without an explicit request. Moreover, some studies reported increased insular activity in meditators, consistent with the hypothesis that meditation helps foster an interoceptive awareness of bodily and emotional states.

Alexithymia in borderline personality disorder is not associated with deficits in automatic visual processing of negative emotional stimuli

Previous studies have suggested that alexithymia may be related to impairments in automatic emotion processing. While it is well established that alexithymia is highly prevalent in individuals with borderline personality disorder (BPD), it is unknown whether this is reflected by an altered automatic processing of emotional stimuli. In the present study we investigated visually evoked event-related potentials using neutral and negative images from the International Affective Pictures System in 26 BPD patients and 26 healthy controls. In line with previous reports, all subjects showed increased late positive potentials (LPP) for negative compared to neutral images. There were, however, no between-group differences at any time point. Crucially, there was no difference between alexithymic and non-alexithymic BPD patients in the expression of LPP. Our study is the first to show that automatic emotion processing in the visual domain appears to be normal in BPD and unaffected by alexithymia.

P.1.i.033 - Excitatory amino acid transporters 1 affects corticolimbic circuitry during implicit processing of negative emotional stimuli in bipolar disorder

P.1.i.033 - Excitatory amino acid transporters 1 affects corticolimbic circuitry during implicit processing of negative emotional stimuli in bipolar disorder

Catechol-O-methyltransferase Val(108/158)Met polymorphism affects fronto-limbic connectivity during emotional processing in bipolar disorder

Catechol-O-methyltransferase (COMT) inactivates catecholamines, Val/Val genotype was associated to an increased amygdala (Amy) response to negative stimuli and can influence the symptoms severity and the outcome of bipolar disorder, probably mediated by the COMT polymorphism (rs4680) interaction between cortical and subcortical dopaminergic neurotransmission. The aim of this study is to explore how rs4680 and implicit emotional processing of negative emotional stimuli could interact in affecting the Amy connectivity in bipolar depression. Forty-five BD patients (34 Met carriers vs. 11 Val/Val) underwent fMRI scanning during implicit processing of fearful and angry faces. We explore the effect of rs4680 on the strength of functional connectivity from the amygdalae to whole brain. Val/Val and Met carriers significantly differed for the connectivity between Amy and dorsolateral prefrontal cortex (DLPFC) and supramarginal gyrus. Val/Val patients showed a significant positive connectivity for all of these areas, where Met carriers presented a significant negative one for the connection between DLPFC and Amy. Our findings reveal a COMT genotype-dependent difference in corticolimbic connectivity during affective regulation, possibly identifying a neurobiological underpinning of clinical and prognostic outcome of BD. Specifically, a worse antidepressant recovery and clinical outcome previously detected in Val/Val patients could be associated to a specific increased sensitivity to negative emotional stimuli.

Epistemic motivation affects the processing of negative emotional stimuli in interpersonal decisions.

The present electrophysiological study investigated the role of the need for cognitive closure (NFC) in emotional processing. The NFC is conceptualized as an epistemic motive that is related to how and why people seek out information in social environments. Event-related potentials were recorded while individuals with high NFC (i.e., low epistemic motivation) or low NFC (i.e., high epistemic motivation) performed a modified Ultimatum Game, in which the emotions of happy or angry game agents were employed to predict their most likely offer. High-NFC participants more closely adhered to the decisions rules of the game than low-NFC individuals did. The electrophysiological results showed that the dispositional NFC modified early perceptual components (N170, N200, and P200). The potentials showed that high-NFC subjects had a processing bias to angry faces, whereas low-NFC individuals exhibited no such effects. These findings indicated that high-NFC individuals were more sensitive to negative emotional stimuli than low-NFC individuals in an interpersonal decision-making task.

Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone-sulfate (DHEAS) and emotional processing — A behavioral and electrophysiological approach

Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone-sulfate (DHEAS) may have mood enhancement effects: higher DHEAS concentrations and DHEA/cortisol ratio have been related to lower depression scores and controlled trials of DHEA administration have reported significant antidepressant effects. The balance between DHEAS and DHEA has been suggested to influence brain functioning. We explored DHEAS, DHEA, cortisol, DHEA/cortisol and DHEAS/DHEA ratios relations to the processing of negative emotional stimuli at behavioral and brain levels by recording the electroencephalogram of 21 young women while performing a visual task with implicit neutral or negative emotional content in an audio–visual oddball paradigm. For each condition, salivary DHEA, DHEAS and cortisol were measured before performing the task and at 30 and 60min intervals. DHEA increased after task performance, independent of the implicit emotional content. With implicit negative emotion, higher DHEAS/DHEA and DHEA/cortisol ratios before task performance were related to shorter visual P300 latencies suggesting faster brain processing under a negative emotional context. In addition, higher DHEAS/DHEA ratios were related to reduced visual P300 amplitudes, indicating less processing of the negative emotional stimuli. With this study, we could show that at the electrophysiological level, higher DHEAS/DHEA and DHEA/cortisol ratios were related to shorter stimulus evaluation times suggesting less interference of the implicit negative content of the stimuli with the task. Furthermore, higher DHEAS/DHEA ratios were related to reduced processing of negative emotional stimuli which may eventually constitute a protective mechanism against negative information overload.

Neural Correlates of Disturbed Emotion Processing in Borderline Personality Disorder: A Multimodal Meta-Analysis

BackgroundDisturbances in the processing and regulation of emotions are core symptoms of borderline personality disorder (BPD). To further elucidate neural underpinnings of BPD, the present meta-analysis summarizes functional neuroimaging findings of emotion processing tasks, as well as structural neuroimaging findings, and investigates multimodally affected brain regions. MethodsCombined coordinate- and image-based meta-analyses were calculated using anisotropic effect size signed differential mapping. Nineteen functional neuroimaging studies investigating the processing of negative compared with neutral stimuli in a total of 281 patients with BPD and 293 healthy control subjects (HC) were included. In addition, 10 studies investigating gray matter abnormalities in 263 patients with BPD and 278 HC were analyzed. ResultsCompared with HC, BPD patients showed relatively increased activation of the left amygdala and posterior cingulate cortex, along with blunted responses of the bilateral dorsolateral prefrontal cortex, during the processing of negative emotional stimuli. The multimodal analysis identified the left amygdala to be characterized by a combination of functional hyperactivity and smaller gray matter volume compared with HC. Hyperresponsivity of the amygdala was moderated by medication status of the patient samples. Medication-free samples were characterized by limbic hyperactivity, whereas no such group differences were found in patients currently taking psychotropic medication. ConclusionsResults strengthen the assumption that dysfunctional dorsolateral prefrontal and limbic brain regions are a hallmark feature of BPD and therefore are consistent with the conceptualization of BPD as an emotion dysregulation disorder.

Functional connectivity between the amygdala and prefrontal cortex in medication-naive individuals with major depressive disorder

Convergent evidence suggests dysfunction within the prefrontal cortex (PFC) and amygdala, important components of a neural system that subserves emotional processing, in individuals with major depressive disorder (MDD). Abnormalities in this system in the left hemisphere and during processing of negative emotional stimuli are especially implicated. In this study, we used functional magnetic resonance imaging (fMRI) to investigate amygdala-PFC functional connectivity during emotional face processing in medication-naive individuals with MDD. Individuals with MDD and healthy controls underwent fMRI scanning while processing 3 types of emotional face stimuli. We compared the strength of functional connectivity from the amygdala between the MDD and control groups. Our study included 28 individuals with MDD and 30 controls. Decreased amygdala-left rostral PFC (rPFC) functional connectivity was observed in the MDD group compared with controls for the fear condition (p < 0.05, corrected). No significant differences were found in amygdala connectivity to any cerebral regions between the MDD and control groups for the happy or neutral conditions. All participants with MDD were experiencing acute episodes, therefore the findings could not be generalized to the entire MDD population. Medication-naive individuals with MDD showed decreased amygdala-left rPFC functional connectivity in response to negative emotional stimuli, suggesting that abnormalities in amygdala-left rPFC neural circuitry responses to negative emotional stimuli might play an important role in the pathophysiology of MDD.

Differential modulation of emotion processing brain regions by noradrenergic and serotonergic antidepressants

Most widely used antidepressant drugs affect the serotonergic and noradrenergic pathways. However, there are currently no neurobiological criteria for selecting between these targets and predicting the treatment response in individual depressed patients. The current study is aimed at differentiating brain regions known to be pathophysiologically and functionally involved in depression-related emotion processing with respect to their susceptibility to serotonergic and noradrenergic modulation. In a single-blind pseudo-randomized crossover study, 16 healthy subjects (out of 21 enrolled) were included in analysis after ingesting a single dose of citalopram (a selective serotonin-reuptake inhibitor, 40mg), reboxetine (a selective noradrenaline-reuptake inhibitor, 8mg), or placebo at three time points prior to functional magnetic resonance imaging (fMRI). During fMRI, subjects anticipated and subsequently viewed emotional pictures. Effects of serotonergic and noradrenergic modulation versus placebo on brain activity during the perception of negative pictures were analyzed with a repeated measures ANOVA in the whole brain and in specific regions of interest relevant to depression. Noradrenergic modulation by reboxetine increased brain activity in the thalamus, right dorsolateral prefrontal cortex and occipital regions during the perception of negative emotional stimuli. Citalopram primarily affected the ventrolateral prefrontal cortical regions. The brain regions involved in the processing of negative emotional stimuli were differentially modulated by selective noradrenergic and serotonergic drugs: thalamic activity was increased by reboxetine, whereas citalopram primarily affected ventrolateral prefrontal regions. Thus, dysfunction in these regions, which could be identified in depressed patients, may predict treatment responses to either noradrenergic or serotonergic antidepressants.

Acute tryptophan depletion attenuates conscious appraisal of social emotional signals in healthy female volunteers.

RationaleAcute tryptophan depletion (ATD) decreases levels of central serotonin. ATD thus enables the cognitive effects of serotonin to be studied, with implications for the understanding of psychiatric conditions, including depression.ObjectiveTo determine the role of serotonin in conscious (explicit) and unconscious/incidental processing of emotional information.Materials and methodsA randomized, double-blind, cross-over design was used with 15 healthy female participants. Subjective mood was recorded at baseline and after 4 h, when participants performed an explicit emotional face processing task, and a task eliciting unconscious processing of emotionally aversive and neutral images presented subliminally using backward masking.ResultsATD was associated with a robust reduction in plasma tryptophan at 4 h but had no effect on mood or autonomic physiology. ATD was associated with significantly lower attractiveness ratings for happy faces and attenuation of intensity/arousal ratings of angry faces. ATD also reduced overall reaction times on the unconscious perception task, but there was no interaction with emotional content of masked stimuli. ATD did not affect breakthrough perception (accuracy in identification) of masked images.ConclusionsATD attenuates the attractiveness of positive faces and the negative intensity of threatening faces, suggesting that serotonin contributes specifically to the appraisal of the social salience of both positive and negative salient social emotional cues. We found no evidence that serotonin affects unconscious processing of negative emotional stimuli. These novel findings implicate serotonin in conscious aspects of active social and behavioural engagement and extend knowledge regarding the effects of ATD on emotional perception.

Rostral anterior cingulate cortex activity mediates the relationship between the depressive symptoms and the medial prefrontal cortex activity

Background Depression is characterized by enhanced self-referential processing of negative emotional stimuli. Imaging studies have suggested that activation of both the medial prefrontal (MPFC) and anterior cingulate cortices (ACC) is associated with self-referential processing. However, whether this pattern of activation occurs in depressed individuals during the self-referential processing of the emotional stimuli had not been investigated to date. Methods Participants were 13 patients with major depressive disorder and 13 normal controls. We used block-designed functional magnetic resonance imaging (fMRI) to investigate neural activity during the self-referential judgments of positive and negative valenced personality trait words. Results Compared with the normal controls, the depressed patients showed hyperactivity in the MPFC and the rostral ACC during the self-referential processing of negative words. In addition, the activity of these regions during self-referential processing of the negative stimuli was correlated with the depressive symptom severity. The rostral ACC activity mediated the correlation between the MPFC activity and the depressive symptoms. Functional connectivity analysis revealed positive connectivities between the MPFC, the rostral ACC, and the amygdala. Limitation Small N and antidepressant effect on imaging data limit the stability of reported findings. Conclusions The relationships between the MPFC, the rostral ACC, and the amygdala appear to reflect an interaction between the self-referential processing and the negative emotional information processing, and we propose that the strong connection between the MPFC and the rostral ACC is associated with depressive symptoms.

Tuning down the emotional brain: An fMRI study of the effects of cognitive load on the processing of affective images

The present research examines whether cognitive load can modulate the processing of negative emotional stimuli, even after negative stimuli have already activated emotional centers of the brain. In a functional magnetic resonance imaging (fMRI) study, participants viewed neutral and negative stimuli that were followed by an attention-demanding arithmetic task. As expected, exposure to negative stimuli led to increased activation in emotional regions (the amygdalae and the right insula). Subsequently induced task load led to increased activation in cognitive regions (right dorsolateral frontal cortex, right superior parietal cortex). Importantly, task load down-regulated the brain's response to negative stimuli in emotional regions. Task load also reduced subjectively experienced negative emotion in response to negative stimuli. Finally, coactivation analyses suggest that during task performance, activity in right dorsolateral frontal cortex was related to activity in the amygdalae and the right insula. Together, these findings indicate that cognitive load is capable of tuning down the emotional brain.