Implicit, But Not Explicit, Emotion Regulation Relieves Unpleasant Neural Responses Evoked by High-Intensity Negative Images

The empirical status of implicit emotion regulation in mood and anxiety disorders: A meta-analytic review

Strategies to successfully regulate negative emotions may be hindered by maladaptive implicit emotion processing tendencies. And while implicit emotion regulation is known to be impaired in many psychiatric disorders, contradictory findings exist within the empirical literature. Therefore, a meta-analysis of implicit emotion regulation in mood and anxiety disorders (major depressive disorder [MDD], bipolar disorder, generalised anxiety disorder, social anxiety disorder, panic disorder, obsessive-compulsive disorder and post-traumatic stress disorder [PTSD]) was performed. Systematic literature searches were conducted in Web of Science, PubMed/MEDLINE, Scopus, and BrainMap for articles published between 2011 and 2024, and inclusion criteria included internationally recognised diagnostic measures (i.e., DSM-5). A total of 23 clinical studies were identified, and using the Newcastle-Ottawa Scale, 21 studies were of excellent quality. Small to medium effect sizes were reported in patients across measures of accuracy (patients [n = 428] vs. controls [n = 412], standardised mean difference [SMD] -0.39, 95% CI [-0.57 to -0.21], p < .0001) and response latency (patients [n = 477] vs. controls [n = 428], SMD 0.38, 95% CI [0.22 to 0.54], p < .0001). The pooled effects of reduced accuracy and longer reaction times in patients were confirmed by separate sub-group analyses for mood and anxiety disorders, with MDD and PTSD reporting the largest effects. Regarding publication bias, Egger's regression test did not indicate funnel plot asymmetry. Recommendations for future research include investigation of dysfunctional implicit emotion regulation as a transdiagnostic characteristic of psychiatric disorders within the Research Domain Criteria (RDoC) framework.

Neural evidence of implicit emotion regulation deficits: An explorative study of comparing PTSD with and without alcohol dependence

BACKGROUND

Previous studies have identified psychiatric comorbidity, including alcohol dependence (AD), as a significant factor in treating posttraumatic stress disorder (PTSD), there is a lack of evidence on how best to treat comorbid PTSD and AD. Poor emotion regulation may be a key potential mechanism of PTSD and AD comorbidity.

METHODS

Seventy-four participants (48 women and 26 men) include three groups: a healthy control group (HC group, N = 20), a PTSD without alcohol dependence group (PTSD without AD group, N = 36), and a PTSD with alcohol dependence group (PTSD with AD group, N = 18). They completed the Shifted Attention Emotion Evaluation Task (SEAT) paradigm while undergoing fMRI.

RESULTS

Gender and hyperarousal symptoms were found to predict the risk of AD. In the whole-brain fMRI data, compared to PTSD without AD, the PTSD with AD group showed significant deactivations in the left middle Occipital Gyri (BA19_L), the right Rolandic Operculum (BA48_R), and the right Lingual Gyri (BA37_R). Furthermore, AD showed a significant correlation with the right Lingual Gyri (BA37_R) in individuals with PTSD.

CONCLUSION

These findings reveal possible neural mechanisms underlying the difference between PTSD patients with and without AD. These regions are involved in visual pathways, memory processing, and spatial cognition within the context of implicit emotion regulation. The observed alterations in these areas may serve as neural diagnostic markers for PTSD comorbid with AD and could be potential targets for developing novel treatments.

fNIRS neurofeedback facilitates emotion regulation: Exploring individual differences over the ventrolateral prefrontal cortex

The ventrolateral prefrontal cortex (VLPFC) plays a pivotal role in emotion regulation, yet the effectiveness of neurofeedback (NF) training targeting the VLPFC remains uncertain, suggesting significant individual differences in outcomes. In this study, we aimed to clarify these differences by enrolling 90 participants, randomly assigned to either an experimental group or a sham group (n = 48/42). Participants in the experimental group underwent VLPFCNF training over eight sessions across two consecutive days, while those in the sham group received random signals from functional near-infrared spectroscopy (fNIRS). To investigate individual variability, participants in the experimental group were further categorized as high or low-efficacy groups based on their training efficiency, determined by the regression slope of VLPFC activity over the sessions. Our results revealed a significant reduction in negative emotions and increased VLPFC activity during emotion regulation in the high-efficacy group, compared to both the low-efficacy group and sham group. Importantly, the benefit in emotion regulation, as reflected by decreased negativity ratings, was predicted by NF training efficiency. Furthermore, the enhancement of VLPFC activity during emotion regulation fully mediated the relationship between NF training efficiency and emotion regulation benefits. Participants with higher VLPFCNF training efficiency exhibited greater engagement of the VLPFC during emotion regulation, leading to superior emotional outcomes. Additionally, VLPFCNF training efficiency was linked to the habitual use of reappraisal strategies in daily life. This study provides novel causal evidence that VLPFCNF training can effectively enhance emotion regulation, highlighting the importance of individual differences in training outcomes. Our findings suggest that NF training targeting the VLPFC offers a promising and personalized intervention strategy for improving emotion regulation, with potential applications for treating emotional disorders. This research underscores the potential of personalized NF approaches, offering new avenues for tailored therapeutic interventions in the future.

The ventromedial prefrontal cortex plays an important role in implicit emotion regulation: A focality-optimized multichannel tDCS study in anxiety individuals

The regulation of emotions is a crucial facet of well-being and social adaptability, with explicit strategies receiving primary attention in prior research. Recent studies, however, emphasize the role of implicit emotion regulation, particularly implicating the ventromedial prefrontal cortex (VMPFC) in association with its implementation. This study delves into the nuanced role of the VMPFC through focality-optimized multichannel transcranial direct current stimulation (tDCS), shedding light on its causal involvement in implicit reappraisal. The primary goal was to evaluate the effectiveness of VMFPC-targeted tDCS and elucidate its role in individuals with high trait anxiety. Participants engaged in implicit and explicit emotion regulation tasks during multichannel tDCS targeting the VMPFC. The outcome measures encompassed negative emotion ratings, pupillary diameter, and saccade count, providing a comprehensive evaluation of emotion regulation efficiency. The intervention exhibited a notable impact, resulting in significant reductions in negative emotion ratings and pupillary reactions during implicit reappraisal, highlighting the indispensable role of the VMPFC in modulating emotional responses. Notably, these effects demonstrated sustained efficacy up to 1 day postintervention. This study underscores the potency of VMPFC-targeted multichannel tDCS in augmenting implicit emotion regulation. This not only contributes insights into the neural mechanisms of emotion regulation but also suggests innovative therapeutic avenues for anxiety disorders. The findings present a promising trajectory for future mood disorder interventions, bridging the gap between implicit emotion regulation and neural stimulation techniques.

Implicit induction of expressive suppression in regulation of happy crowd emotions

Implicit emotion regulation provides an effective means of controlling emotions triggered by a single face without conscious awareness and effort. Crowd emotion has been proposed to be perceived as more intense than it actually is, but it is still unclear how to regulate it implicitly. In this study, participants viewed sets of faces of varying emotionality (e.g. happy to angry) and estimated the mean emotion of each set after being primed with an expressive suppression goal, a cognitive reappraisal goal, or a neutral goal. Faster discrimination for happy than angry crowds was observed. After induction of the expressive suppression goal instead of the cognitive reappraisal goal, augmented N170 and early posterior negativity (EPN) amplitudes, as well as attenuated late positive potential (LPP) amplitudes, were observed in response to happy crowds compared to the neutral goal. Differential processing of angry crowds was not observed after the induction of both regulatory goals compared to the neutral goal. Our findings thus reveal the happy-superiority effect and that implicit induction of expressive suppression improves happy crowd emotion recognition, promotes selective coding, and successfully downregulates the neural response to happy crowds.

Theta-band Connectivity within Cognitive Control Brain Networks Suggests Common Neural Mechanisms for Cognitive and Implicit Emotional Control

Self-control is a core aspect of adaptive human behavior. It allows the attainment of personal goals by regulating unwanted thoughts, emotions, and behavior. Previous research highlighted the crucial role of cognitive control for explicitly pursued self-control and explicit emotion regulation strategies (such as cognitive reappraisal or attentional distraction). The present study investigated whether similar neural mechanisms would be involved in an implicit self-control task that acted as a covert emotion regulation strategy. Thirty-six female participants unscrambled sentences of either neutral (no-regulation condition) or neutral and self-control-related content (regulation condition) before passively viewing negative and neutral pictures. Compared with the no-regulation condition, implicit induction of self-control reduced the amplitude of the late positive potential to negative pictures, indicating successful emotion downregulation. Crucially, implicit self-control enhanced connectivity within the two cognitive control brain networks in the theta frequency band. Specifically, for the frontoparietal network, increased connectivity from the dorsolateral PFC to the intraparietal cortex was observed. For the cingulo-opercular network, increased connectivity from dorsal anterior cingulate cortex to the left anterior insula/frontal operculum and from the right anterior insula/frontal operculum to the dorsal anterior cingulate cortex was observed. These effects were accompanied by a decrease in prestimulus alpha power in the right primary visual cortex, suggesting adjustment of attentional and perceptual processes in preparation for the upcoming affective stimulation. Together, our results indicate that self-control enhances cognitive control that is necessary for setting, maintaining, and monitoring the achievement of self-control behavior, as well as regulation of attentional and emotional processes.