Noga Cohen

Dynamic modulation of emotional processing

Recent findings suggest the processing of emotional stimuli is prioritized compared to neutral stimuli; however, it is not necessarily automatic and depends on several modulating factors. The current paper highlights three major factors that affect the reactions to emotional stimuli: (i) stimulus properties, (ii) task demands and attention, and (iii) individual characteristics. The evidence reviewed here suggests that individual characteristics shape the structure, function and connectivity within a neural network that is involved in the reactions to emotional stimuli. This neural network includes regions related to emotion and attention, in line with evidence for reciprocal connections between these two processes. Activation in this network further depends on the emotional value of a certain item, as well as physical features of the stimulus. This integrative view can lead to better understanding of the underlying mechanisms of emotional reactions, as well as better therapeutic approaches.

Linking Executive Control and Emotional Response

Rumination, a maladaptive self-reflection, is a risk factor for depression, thought to be maintained by executive control deficits that impair ruminators’ ability to ignore emotional information. The current research examined whether training individuals to exert executive control when exposed to negative stimuli can ease rumination. A total of 85 participants were randomly assigned to one of two training conditions. In the experimental condition activation of executive control was followed predominantly by the presentation of negative pictures, whereas in the control condition it was followed predominantly by neutral pictures. As predicted, participants in the experimental group showed reduced state rumination compared with those in the control group. Furthermore, trait rumination, and particularly its maladaptive subtype brooding, was associated with increased sadness only among participants in the control group, and not in the experimental group. We argue that training individuals to exert executive control when processing negative stimuli can alleviate ruminative thinking and rumination-related sad mood.

Can Emotion Modulate Attention? Evidence for Reciprocal Links in the Attentional Network Test

Evolution theory suggests that adaptive behavior depends on our ability to give preferential attention to emotional information when it is necessary for our survival, and to down-regulate irrelevant emotional influence. However, empirical work has shown that the interaction between emotion and attention varies, based on the attentional network in question. The aim of the current research was to examine the influence of stimulus emotionality on attention in three attentional networks: alerting, orienting, and executive functions. In two studies, using negative and neutral cues in a modified version of the Attention Network Test, it was found that negative cues impaired task performance in the absence of executive conflict, but not when executive processes were activated. Moreover, it was found that the influence of negative cues on task performance in a given trial was attenuated following activation of executive processes in the previous trial. These results suggest that when executive resources are required, inhibitory mechanisms are recruited to decrease the disruptive effect of emotional stimuli. More importantly, these findings indicate that the effect of emotional stimuli on attention is down-regulated both during cognitive conflict and after the conflict has already ended.

Stop feeling: inhibition of emotional interference following stop-signal trials.

Although a great deal of literature has been dedicated to the mutual links between emotion and the selective attention component of executive control, there is very little data regarding the links between emotion and the inhibitory component of executive control. In the current study we employed an emotional stop-signal task in order to examine whether emotion modulates and is modulated by inhibitory control. Results replicated previous findings showing reduced inhibitory control [longer stop-signal reaction time (SSRT)] following negative, compared to neutral pictures. Most importantly, results show decreased emotional interference following stop-signal trials. These results show that the inhibitory control component of executive control can serve to decrease emotional effects. We suggest that inhibitory control and emotion have a two-way connection in which emotion disrupts inhibitory control and activation of inhibitory control disrupts emotion.

Executive control attenuates emotional effects-For high reappraisers only?

Irrelevant emotional information influences adaptive behavior. Previous results demonstrated that executive control may help reduce such influence. The current research studied the relationship between the tendency to use emotion regulation strategies (e.g., reappraisal and suppression) and the ability of executive control to reduce emotional interference. Our results demonstrate that negative stimuli disrupt performance in congruent flanker trials, regardless of individual tendencies to use reappraisal or suppression. In contrast, negative stimuli did not disrupt performance in incongruent trials in people who report frequent use of reappraisal. This pattern appeared both when a negative stimulus appeared before and after the flanker target and was not modulated by suppression level. We suggest that people who tend to use reappraisal have improved ability of executive control to reduce emotional effects.

Do irrelevant emotional stimuli impair or improve executive control

Our behavior is constantly influenced by emotional stimuli. These stimuli can enhance (i.e., improve) or impair performance, depending on their specific interaction with situational demands (Dolcos et al., 2011). This paper examines factors that mediate the influence of task-irrelevant negative stimuli on executive control (EC). We demonstrate how similar results of emotion-cognition interactions might be interpreted according to opposing theories, following the use of different analysis methods. Executive control is responsible for monitoring, controlling, and regulating irrelevant information, in order to enable goal-directed behavior (Norman and Shallice, 1986). Recently, there is growing debate regarding the influence of negative stimuli on EC (Hu et al., 2012). Specifically, compared to neutral stimuli, negative stimuli were found to impair (i.e., elongated reaction times – RT), improve (i.e., facilitated RT), or have no influence (i.e., similar RT) on EC. Herein we will first suggest that descriptions of improved or impaired EC may be misleading, and then discuss three factors that modulate links between EC and emotion: available resources, attentional breadth, and top-down modulation.

Using executive control training to suppress amygdala reactivity to aversive information

The ability to regulate emotions is essential for adaptive behavior. This ability is suggested to be mediated by the connectivity between prefrontal brain regions and the amygdala. Yet, it is still unknown whether the ability to regulate emotions can be trained by using a non-emotional procedure, such as the recruitment of executive control (EC). Participants who were trained using a high-frequent executive control (EC) task (80% incongruent trials) showed reduced amygdala reactivity and behavioral interference of aversive pictures. These effects were observed only following multiple-session training and not following one training session. In addition, they were not observed for participants exposed to low-frequent EC training (20% incongruent trials). Resting-state functional connectivity analysis revealed a marginally significant interaction between training group and change in the connectivity between the amygdala and the right inferior frontal gyrus (IFG). Amygdala-IFG connectivity was significantly increased following the training only in the high-frequent EC training group. These findings are the first to show that non-emotional training can induce changes in amygdala reactivity to aversive information and alter amygdala-prefrontal connectivity.

Peri-encoding predictors of memory encoding and consolidation

We review reports of brain activations that occur immediately prior to the onset or following the offset of to-be-remembered information and can predict subsequent mnemonic success. Memory-predictive pre-encoding processes, occurring from fractions of a second to minutes prior to event onset, are mainly associated with activations in the medial temporal lobe (MTL), amygdala and midbrain, and with enhanced theta oscillations. These activations may be considered as the neural correlates of one or more cognitive operations, including contextual processing, attention, and the engagement of distinct computational modes associated with prior encoding or retrieval. Post-encoding activations that correlate with subsequent memory performance are mainly observed in the MTL, sensory cortices and frontal regions. These activations may reflect binding of elements of the encoded information and initiation of memory consolidation. In all, the findings reviewed here illustrate the importance of brain states in the immediate peri-encoding time windows in determining encoding success. Understanding these brain states and their specific effects on memory may lead to optimization of the encoding of desired memories and mitigation of undesired ones.

Inhibition of negative content—a shared process in rumination and reappraisal

People vary in how they cope with negative events. Some people become immersed in repetitive ruminative thinking concerning the event, whereas others employ reappraisal and attempt to interpret the event in less negative ways. Interestingly, although both reappraisal and rumination involve active processing of negative situations rather than avoiding their affective value, these two strategies lead to opposite outcomes. Whereas rumination is maladaptive and is a risk factor for psychopathology, reappraisal is adaptive and has been linked to emotional well-being (for a meta-analysis see Aldao et al., 2010). In the current paper, we examine a shared process that may play a role in both rumination and reappraisal. We suggest that inhibition of irrelevant, negatively valenced information while pursuing a goal or performing a task underlies both rumination and reappraisal. We present correlational and causal findings linking impaired inhibition of negative content with reduced reappraisal and with increased tendency to ruminate. We postulate possible pathways for the links between inhibition of negative content and these two emotion regulation strategies.

Executive control suppresses pupillary responses to aversive stimuli.

Adaptive behavior depends on the ability to effectively regulate emotional responses. Continuous failure in the regulation of emotions can lead to heightened physiological reactions and to various psychopathologies. Recently, several behavioral and neuroimaging studies showed that exertion of executive control modulates emotion. Executive control is a high-order operation involved in goal-directed behavior, especially in the face of distractors or temptations. However, the role of executive control in regulating emotion-related physiological reactions is unknown. Here we show that exercise of executive control modulates reactivity of both the sympathetic and the parasympathetic components of the autonomic nervous system. Specifically, we demonstrate that both pupillary light reflex and pupil dilation for aversive stimuli are attenuated following recruitment of executive control. These findings offer new insights into the very basic mechanisms of emotion processing and regulation, and can lead to novel interventions for people suffering from emotion dysregulation psychopathologies.