title: The influence of work-related chronic stress on the regulation of emotion and on functional connectivity in the brain.
abstract: Despite mounting reports about the negative effects of chronic occupational stress on cognitive and emotional functions, the underlying mechanisms are unknown. Recent findings from structural MRI raise the question whether this condition could be associated with a functional uncoupling of the limbic networks and an impaired modulation of emotional stress. To address this, 40 subjects suffering from burnout symptoms attributed to chronic occupational stress and 70 controls were investigated using resting state functional MRI. The participants' ability to up- regulate, down-regulate, and maintain emotion was evaluated by recording their acoustic startle response while viewing neutral and negatively loaded images. Functional connectivity was calculated from amygdala seed regions, using explorative linear correlation analysis. Stressed subjects were less capable of down-regulating negative emotion, but had normal acoustic startle responses when asked to up-regulate or maintain emotion and when no regulation was required. The functional connectivity between the amygdala and the anterior cingulate cortex correlated with the ability to down-regulate negative emotion. This connectivity was significantly weaker in the burnout group, as was the amygdala connectivity with the dorsolateral prefrontal cortex and the motor cortex, whereas connectivity from the amygdala to the cerebellum and the insular cortex were stronger. In subjects suffering from chronic occupational stress, the functional couplings within the emotion- and stress-processing limbic networks seem to be altered, and associated with a reduced ability to down-regulate the response to emotional stress, providing a biological substrate for a further facilitation of the stress condition.
authors.affiliation: Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden.
authors.forename: Armita
authors.initials: A
authors.lastname: Golkar
authors.affiliation: Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden.
authors.forename: Emilia
authors.initials: E
authors.lastname: Johansson
authors.affiliation: Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden.
authors.forename: Maki
authors.initials: M
authors.lastname: Kasahara
authors.affiliation: Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden; Center for Social Sustainability, Department of Neurobiology, Care Sciences and Society, Karolinska institute, Stockholm, Sweden.
authors.forename: Walter
authors.initials: W
authors.lastname: Osika
authors.affiliation: Stress Research Institute, Stockholm University, Stockholm, Sweden.
authors.forename: Aleksander
authors.initials: A
authors.lastname: Perski
authors.affiliation: Department of Women's and children's health, and Neurology Clinic, Karolinska Institute and Hospital, Stockholm, Sweden.
authors.forename: Ivanka
authors.initials: I
authors.lastname: Savic
mesh_terms: D000328:Adult; D000679:Amygdala / Q000473:pathology / Q000503:physiopathology; D001931:Brain Mapping; D002055:Burnout, Professional / Q000473:pathology / Q000503:physiopathology*; D016022:Case-Control Studies; D002531:Cerebellum / Q000473:pathology / Q000503:physiopathology; D002908:Chronic Disease; D004644:Emotions; D005260:Female; D006179:Gyrus Cinguli / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000473:pathology / Q000503:physiopathology; D009434:Neural Pathways / Q000473:pathology / Q000503:physiopathology*; D017397:Prefrontal Cortex / Q000473:pathology / Q000503:physiopathology; D013216:Reflex, Startle