title: Modulation of induced frontocentral theta (Fm-θ) event-related (de-)synchronisation dynamics following mindfulness-based cognitive therapy in Major Depressive Disorder.
abstract: Depressive severity has been associated with attenuated neocortical frontal midline theta (Fm-θ) power/evoked activity. Mindfulness-Based Cognitive Therapy (MBCT) has shown to be a successful novel intervention for Major Depressive Disorder (MDD), albeit precise working mechanisms remain elusive. We examined the hypothesis that MBCT would have modulating effects upon evoked Fm-θ power, in addition to investigating possible mediation of induced event-related de/synchronisation (ERD/ERS) dynamics. Fifty one patients with a primary diagnosis of MDD (26 exposed to MBCT vs. 25 wait-list/WL controls) undertook a Go/NoGo task consisting of positive, negative and neutral words, further stratified into abstract versus trait adjective matrices. Depressive symptom severity and rumination were also examined. A pattern of enhanced induced Fm-θ synchronisation during the latter 400-800 ms temporal-window pre-to-post MBCT was observed; the contrary in the WL. Modulated ERD/ERS dynamics correlated to amelioration in depressive and rumination symptoms in the MBCT group. We propose the primary action pathway alluded to a neural disengagement mechanism enacting upon tonic neuronal assemblies implicated in emotional and self-related processing. Due to the complexity and presently undiscovered complete unified scientific understanding of neuro-oscillatory-dynamics, and associated clinical interplays; we hypothesise that the electro-cortical and connected clinical working pathways of MBCT in depression are multi-levelled constituting nonlinear and interdependent mechanisms, represented by mediated EEG synchronisation dynamics.
authors.affiliation: Faculty of Science, Intelligent Systems, Radboud University Nijmegen, Postbus 9010, 6500 GL Nijmegen, The Netherlands ; Department of Cognitive Neuroscience, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands ; Netherlands Institute for Advanced Study, Wassenaar, The Netherlands.
authors.forename: Poppy L A
authors.initials: PL
authors.lastname: Schoenberg
authors.affiliation: Department of Psychiatry, Radboud University Medical Centre Nijmegen, Nijmegen, The Netherlands.
authors.forename: Anne E M
authors.initials: AE
authors.lastname: Speckens
keywords: Event-related (de-)synchronisation (ERD/ERS); Fm-theta; Major Depressive Disorder (MDD); Mindfulness-Based Cognitive Therapy (MBCT); Oscillatory EEG; Rumination