Emdr Therapy Changes the Resting-state Eeg

Abstract

Introduction During the Eye Movement Desensitization and Reprocessing (EMDR) changes of brain electrical activity was recently demonstrated in victims of psychological traumas. Objectives Thirty-one victims of psychological traumas were investigated at the first EMDR session (t0) and at the last one performed after processing the index trauma (t1). Aims To investigate differences in EEG source activity and EEG source functional connectivity (EEG-SFC) in eyes closed condition before the beginning of t0 and t1 EMDR therapy session. Methods Electrical source activity was computed by eLORETA from a 37-channel EEG. EEG-SFC analysis was based on the lagged phase synchronization (LPS), derived by a two-step eLORETA procedure: dimensionality reduction of inverse matrix from 6239 voxels to 28 regions of interest (ROIs); LPS indices computation, for each spectrum band, in all possible ROI pairs. Results Resting-state EEG source activity resulted in a low frequency increase of posterior cingulate cortex and a high frequency (beta2 and gamma) decrease in right prefrontal and parietal cortex between t0 and t1. Significant enhancements of EEG-SFC were detected in t1 respect to t0 between ROI pairs of theta band right temporo-parahippocampal regions and alpha band fronto-parietal regions. Conclusions Significant modifications of resting-state electrical brain activity were present after EMDR therapy. These findings suggest that the elaboration of psychological traumas induced by EMDR produces, in a resting-state condition, an enhancement of activity and functional connectivity of cerebral sources involved in cognitive control and emotional processing.