Eeg Coherence between Prefrontal and Posterior Cortical Regions is Related to Negative Personality Traits

A mind-body lifestyle intervention enhances emotional control in patients with major depressive disorder: a randomized, controlled study

To investigate the effects of the Dejian mind-body intervention (DMBI), on depressive symptoms and electroencephalography (EEG) changes in relation to emotional processing in patients with depression. Seventy-five age-, gender-, and education-matched participants with depression were randomly assigned to receive either Cognitive Behavior Therapy (CBT) or DMBI or were placed in a control group. Overall depressive syndrome, specific mood-related symptoms (Hamilton Psychiatric Rating Scale for Depression, Beck Depression Inventory), and EEG data were collected individually during a resting state and during affective image viewing before and after 10 weeks of intervention. After intervention, both the DMBI and CBT groups showed significantly reduced levels of overall depressive syndrome and mood-related symptoms (Ps ≤ 0.002) than the control group. In addition, the DMBI group demonstrated a significantly greater extent of elevation in fronto-posterior EEG theta coherence on the right hemisphere when viewing different mood-induction (neutral, positive, and negative) stimuli than the CBT and control groups (Ps < 0.03). The elevated intra-right fronto-posterior coherence when viewing mood-induction stimuli correlated with improved mood levels after the intervention (Ps < 0.05). Our findings also showed that, only in the DMBI group, there was a significant suppression of theta source activity at the posterior and subcortical brain regions that are known to mediate negative emotional responses and the self-absorbed mode of thinking. The findings of reduced depressive symptoms and elevated frontoposterior coherence suggest that the DMBI can enhance emotional control in depression.

Prefrontal-posterior coupling mediates transitions between emotional states and influences executive functioning

Emotions often result from fluctuating experiences with self-regulation unfolding over time. However, most research has been focused on neural responses to static, affective stimuli. We studied emotion transitions, which correspond to dynamic conditions of varying affective valence or intensities. Functional coupling of prefrontal and posterior cortex (EEG coherence) was recorded during exposure to stable versus changing emotion-eliciting images (static vs. dynamic conditions). Prefrontal-posterior coupling was decreased in the dynamic conditions compared to the static conditions. A decrease in prefrontal-posterior coupling implies less control of the prefrontal cortex over perceptual information, which may allow the brain to become more affected by emotional fluctuations. We also assessed the aftereffect of EEG coherence on executive functioning, utilizing the flanker task. Among individuals reporting higher chronic stress, executive functioning decreased after dynamic conditions. This decrease in executive functioning was mediated by the decrease in prefrontal-posterior coupling in the dynamic conditions. These findings suggest that the strength of prefrontal-posterior coupling is not only related to emotional transitions but also to executive functioning. The deterioration of executive functioning after dynamic emotional processing may reflect the additional cognitive effort required to process dynamic shifts in affective stimuli, and this relationship is exacerbated by chronic stress.

Functional connectivity in major depression: increased phase synchronization between frontal cortical EEG-source estimates

Structural and metabolic alterations in prefrontal brain areas, including the subgenual (SGPFC), medial (MPFC) and dorsolateral prefrontal cortex (DLPFC), have been shown in major depressive disorder (MDD). Still it remains largely unknown how brain connectivity within these regions is altered at the level of neuronal oscillations. Therefore, the goal was to analyze prefrontal electroencephalographic phase synchronization in MDD and its changes after antidepressant treatment. In 60 unmedicated patients and 60 healthy controls (HC), a 15-min resting electroencephalogram (EEG) was recorded in subjects at baseline and in a subgroup of patients after 2 weeks of antidepressant medication. EEG functional connectivity between the SGPFC and the MPFC/DLPFC was assessed with eLORETA (low resolution brain electromagnetic tomography) by means of lagged phase synchronization. At baseline, patients revealed increased prefrontal connectivity at the alpha frequency between the SGPFC and the left DLPFC/MPFC. After treatment, an increased connectivity between the SGPFC and the right DLPFC/MPFC at the beta frequency was found for MDD. A positive correlation was found for baseline beta connectivity and reduction in scores on the Hamilton depression rating scale. MDD is characterized by increased EEG functional connectivity within frontal brain areas. These EEG markers of disturbed neuronal communication might have potential value as biomarkers.

Prefrontal-posterior coupling while observing the suffering of other people, and the development of intrusive memories

Witnessing the suffering of others, for instance, in hospital emergency rooms but also through televised images in news or reality programs, may be associated with the occurrence of later intrusive memories. The factors contributing to why some people develop intrusive memories and others do not are still poorly understood. N = 121 healthy women were exposed to film scenes showing the suffering of dying, severely injured, and mourning people while their EEG was recorded. Individuals showing greater decreases of functional coupling between prefrontal and posterior cortices (greater decreases of EEG beta coherences) reported more intrusive memories of the witnessed events. This was shown for intrusions in the short term (immediately after viewing the film) as well as in the medium term (intrusive memories over 1 week). The findings illuminate brain mechanisms involved in the encoding of information in ways that make intrusive memories more likely.