Cerebral Correlates of Abnormal Emotion Conflict Processing in Euthymic Bipolar Patients: A Functional MRI Study

Abstract

BackgroundPatients with bipolar disorder experience cognitive and emotional impairment that may persist even during the euthymic state of the disease. These persistent symptoms in bipolar patients (BP) may be characterized by disturbances of emotion regulation and related fronto-limbic brain circuitry. The present study aims to investigate the modulation of fronto-limbic activity and connectivity in BP by the processing of emotional conflict.MethodsFourteen euthymic BP and 13 matched healthy subjects (HS) underwent functional magnetic resonance imaging (fMRI) while performing a word-face emotional Stroop task designed to dissociate the monitoring/generation of emotional conflict from its resolution. Functional connectivity was determined by means of psychophysiological interaction (PPI) approach.ResultsRelative to HS, BP were slower to process incongruent stimuli, reflecting higher amount of behavioral interference during emotional Stroop. Furthermore, BP showed decreased activation of the right dorsolateral prefrontal cortex (DLPFC) during the monitoring and a lack of bilateral amygdala deactivation during the resolution of the emotional conflict. In addition, during conflict monitoring, BP showed abnormal positive connectivity between the right DLPFC and several regions of the default mode network.ConclusionsOverall, our results highlighted dysfunctional processing of the emotion conflict in euthymic BP that may be subtended by abnormal activity and connectivity of the DLPFC during the conflict monitoring, which, in turn, leads to failure of amygdala deactivation during the resolution of the conflict. Emotional dysregulation in BP may be underpinned by a lack of top-down cognitive control and a difficulty to focus on the task due to persistent self-oriented attention.

Widespread white matter microstructural abnormalities in bipolar disorder: evidence from mega- and meta-analyses across 3033 individuals

“…Neural models of BD suggest a role of fronto-limbic dysconnectivity in the emergence of mood symptoms of BD [3,4]. This model is mainly supported by results from functional MRI (fMRI) studies demonstrating that emotional instability in this disorder might be underpinned by abnormal connectivity between frontal and limbic regions [5,6]. However, results from diffusion tensor imaging (DTI) studies, a technique that allows the exploration of structural connectivity in vivo, have highlighted far more extensive brain abnormalities in BD.…”

Dysfunctional gaze processing in bipolar disorder

“…When viewing emotional faces, BP perform worse in emotional face labeling ( Favre et al, 2015 , Kohler et al, 2011 ), and show hyperactivity in limbic regions ( Surguladze et al, 2010 ). Even with neutral faces, BP show increased amygdala activation ( Kim et al, 2012 , Rich et al, 2006 ) and tend to perceive these faces as more hostile than healthy controls ( Rich et al, 2006 ).…”

Fronto-limbic neural variability as a transdiagnostic correlate of emotion dysregulation

“…Furthermore, neural activation and connectivity of fronto-limbic regions, especially the ACC, amygdala, insula, and vlPFC, showed changes following psychotherapy aimed at improving emotion regulation in BPD patients (Marceau et al, 2018). Abnormal patterns of activity and connectivity of fronto-limbic regions have been reported in euthymic BD patients, especially involving the amygdala and the medial PFC at rest (Favre et al, 2014; Rey et al, 2016), and during emotion regulation tasks (Favre et al, 2015; Rey et al, 2014). Moreover, psychosocial intervention in individuals with BD or at risk for BD may induce functional and structural changes in these regions (Favre et al, 2016, 2013; Garrett et al, 2015).…”