The impact of melancholia versus non-melancholia on resting-state, EEG alpha asymmetry: electrophysiological evidence for depression heterogeneity

Candice R Quinn; Chris J Rennie; Anthony W F Harris; Andrew H Kemp

doi:10.1016/j.psychres.2013.12.049

The impact of melancholia versus non-melancholia on resting-state, EEG alpha asymmetry: electrophysiological evidence for depression heterogeneity

Psychiatry Res. 2014 Mar 30;215(3):614-7. doi: 10.1016/j.psychres.2013.12.049. Epub 2014 Jan 9.

Authors

Candice R Quinn¹, Chris J Rennie², Anthony W F Harris³, Andrew H Kemp⁴

Affiliations

¹ Discipline of Psychiatry, Sydney Medical School, University of Sydney, Australia.
² School of Physics, University of Sydney, Sydney, New South Wales, Australia; Brain Dynamics Centre, University of Sydney, Westmead Hospital, Australia.
³ Discipline of Psychiatry, Sydney Medical School, University of Sydney, Australia; Brain Dynamics Centre, University of Sydney, Westmead Hospital, Australia.
⁴ Discipline of Psychiatry, Sydney Medical School, University of Sydney, Australia; University of Sydney Cognitive and Affective Neuroscience (SCAN) Research and Teaching Unit, School of Psychology, University of Sydney, Australia; University Hospital and Faculty of Medicine, University of São Paulo, São Paulo, Brazil. Electronic address: andrew.kemp@sydney.edu.au.

PMID: 24467874
DOI: 10.1016/j.psychres.2013.12.049

Abstract

While depression has been associated with relatively greater right than left frontal cortical activity - a neurophysiological marker reflecting greater activation of the withdrawal system - contradictory findings have been reported. It was hypothesised that melancholia would be associated with relative right frontal activation, in comparison to non-melancholia and controls. We collected 2-min of resting-state, eyes closed, electroencephalographic activity from a total of 237 participants including 117 patients with major depressive disorder (57 with melancholia, 60 with non-melancholia) and 120 healthy controls. In contrast to hypotheses, patients with non-melancholia displayed relative left frontal activation in comparison to controls and those with melancholia. These findings were associated with a small to moderate effect size (Cohen's d=0.30-0.34). Critically, patients with melancholic subtype did not differ from controls despite increased severity - relative to those with non-melancholia - on clinical measures. These results may reflect an increase in approach tendencies in patients with non-melancholia including reassurance seeking, anger or irritable aggression. Findings highlight the need for further research on the heterogeneity MDD.

Keywords: Alpha asymmetry; Depression; EEG; Electroencephalography; Melancholia; Non-melancholia.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Cerebral Cortex / physiopathology*
Depression / diagnosis*
Depression / physiopathology
Depressive Disorder / diagnosis*
Depressive Disorder / physiopathology
Electroencephalography*
Female
Frontal Lobe / physiopathology*
Humans
Male
Middle Aged