Lee TW, Wu YT, Yu YW, Chen MC, Chen TJ. The implication of functional connectivity strength in predicting treatment response of major depressive disorder: a resting EEG study. Psychiatry Res 194: 372-377

Laureate Institute for Brain Research, Tulsa, OK, USA.
Psychiatry Research (Impact Factor: 2.68). 12/2011; 194(3):372-7. DOI: 10.1016/j.pscychresns.2011.02.009
Source: PubMed

ABSTRACT Predicting treatment response in major depressive disorder (MDD) has been an important clinical issue given that the initial intent-to-treat response rate is only 50 to 60%. This study was designed to examine whether functional connectivity strengths of resting EEG could be potential biomarkers in predicting treatment response at 8 weeks of treatment. Resting state 3-min eyes-closed EEG activity was recorded at baseline and compared in 108 depressed patients. All patients were being treated with selective serotonin-reuptake inhibitors. Baseline coherence and power series correlation were compared between responders and non-responders evaluated at the 8th week by Hamilton Depression Rating Scale. Pearson correlation and receiver operating characteristic (ROC) analyses were applied to evaluate the performance of connectivity strengths in predicting/classifying treatment responses. The connectivity strengths of right fronto-temporal network at delta/theta frequencies differentiated responders and non-responders at the 8th week of treatment, such that the stronger the connectivity strengths, the poorer the treatment response. ROC analyses supported the value of these measures in classifying responders/non-responders. Our results suggest that fronto-temporal connectivity strengths could be potential biomarkers to differentiate responders and slow responders or non-responders in MDD.

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    • " to - moment control and allocation of sensory resources and specialised processing ( Sadaghiani et al . 2012 ) . Related findings show enhanced right - intra - hemi - spheric coherence over fronto - temporal low frequency bands , i . e . delta and theta frequencies have been connected to poorer treatment response to anti - depressant medication ( Lee et al . 2011 ) . Therefore , it is reasonable to surmise that enhanced left - hemispheric α - coherence possibly served as an ' enabling mechanism ' towards the cohesive imple - mentation of conjoining action pathways ."
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    • "These differences can be explained in part by differences in the connectivity measures used: While Lee et al. and Leuchter et al. used a coherence measure that is not totally independent of amplitude, the phase-synchronization measure used in the present study did not rely on any amplitude information . Fingelkurts et al. (2007) and also Lee et al. (2011) used a measure that calculated connectivity based on power rather than phase synchronization. Therefore, their results reflect different aspects of neuronal interaction. "
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