Chronic stress; Depression; Frontal alpha asymmetry; Illness anxiety; Somatoform disorders; Physiology (medical); Neuropsychology and Physiological Psychology; General Neuroscience
Abstract :
[en] Cardinal characteristics of somatoform disorders (SFDs) are worry of illness, and impaired affective processing. We used relative frontal alpha asymmetry (FAA), a method to measure functional lateralization of affective processing, to investigate psychobiological correlates of SFDs. With alpha activity being inversely related to cortical network activity, relative FAA refers to alpha activity on the right frontal lobe minus alpha activity on the left frontal lobe. Less relative left frontal activity, reflected by negative FAA scores, is associated with lower positive and greater negative affectivity, such as observed in depression. Due to its negative affective component (illness anxiety), we expected to find less relative left frontal activity pattern in SFDs, and positive associations with self-reported chronic stress and depression symptoms. We recorded resting-state EEG activity with 64 electrodes, placed in a 10-10 system in 26 patients with a primary SFD, 23 patients with a major depressive disorder and 25 healthy control participants. The groups did not differ in FAA. Nevertheless, across all participants, less relative left frontal activity was associated with chronic stress and depression symptoms. We concluded that FAA may not serve as an indicator of SFDs. As the relationship of FAA and depressive symptoms was fully mediated by chronic stress, future studies have to clarify whether the association between FAA and chronic stress may represent a shared underlying factor for the manifestation of mental health complaints, such as depression.
DIEROLF, Angelika ; University of Luxembourg > Faculty of Humanities, Education and Social Sciences (FHSE) > Department of Behavioural and Cognitive Sciences (DBCS) > Health and Behaviour
LUTZ, Annika ; University of Luxembourg > Faculty of Humanities, Education and Social Sciences (FHSE) > Department of Behavioural and Cognitive Sciences (DBCS) > Health and Behaviour
VÖGELE, Claus ; University of Luxembourg > Faculty of Humanities, Education and Social Sciences (FHSE) > Department of Behavioural and Cognitive Sciences (DBCS) > Health and Behaviour
Voderholzer, Ulrich; Schoen Clinic Roseneck, Prien am Chiemsee, Germany, Clinic for Psychiatry and Psychotherapy, University Hospital, Ludwig-Maximilians-University of Munich, Munich, Germany
Koch, Stefan; Schoen Clinic Roseneck, Prien am Chiemsee, Germany
Bach, Michael; Practice for Psychosomatics and Stress Medicine, Vienna, Austria
Asenstorfer, Carina; Salzkammergut Clinic Vöcklabruck, Vöcklabruck, Austria
Michaux, Gilles; Research Group 'Brain-Body Interaction', Department of Behavioural and Cognitive Sciences, University of Luxembourg, Esch-sur-Alzette, Luxembourg, GesondheetsZentrum, Fondation Hôpitaux Robert Schuman, Luxembourg, Luxembourg
MERTENS, Vera-Christina ; University of Luxembourg > Faculty of Humanities, Education and Social Sciences > Department of Behavioural and Cognitive Sciences > Health and Behaviour
SCHULZ, André ; University of Luxembourg > Faculty of Humanities, Education and Social Sciences (FHSE) > Department of Behavioural and Cognitive Sciences (DBCS) > Health and Behaviour
External co-authors :
yes
Language :
English
Title :
Frontal alpha asymmetry is associated with chronic stress and depression, but not with somatoform disorders.
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