Brain electrical tomography in depression: the importance of symptom severity, anxiety, and melancholic features.
BACKGROUND
The frontal lobe has been crucially involved in the neurobiology of major depression, but inconsistencies among studies exist, in part due to a failure of considering modulatory variables such as symptom severity, comorbidity with anxiety, and distinct subtypes, as codeterminants for patterns of brain activation in depression.


METHODS
Resting electroencephalogram was recorded in 38 unmedicated subjects with major depressive disorder and 18 normal comparison subjects, and analyzed with a tomographic source localization method that computes the cortical three-dimensional distribution of current density for standard electroencephalogram frequency bands. Symptom severity and anxiety were measured via self-report and melancholic features via clinical interview.


RESULTS
Depressed subjects showed more excitatory (beta3, 21.5-30.0 Hz) activity in the right superior and inferior frontal lobe (Brodmann's area 9/10/11) than comparison subjects. In melancholic subjects, this effect was particularly pronounced for severe depression, and right frontal activity correlated positively with anxiety. Depressed subjects showed posterior cingulate and precuneus hypoactivity.


CONCLUSIONS
While confirming prior results implicating right frontal and posterior cingulate regions, this study highlights the importance of depression severity, anxiety, and melancholic features in patterns of brain activity accompanying depression.
Department of Psychology, University of Wisconsin-Madison, 57305-2280, USA.
Diego A
DA
Pizzagalli
Jack B
JB
Nitschke
Terrence R
TR
Oakes
Andrew M
AM
Hendrick
Kathryn A
KA
Horras
Christine L
CL
Larson
Heather C
HC
Abercrombie
Stacey M
SM
Schaefer
John V
JV
Koger
Ruth M
RM
Benca
Roberto D
RD
Pascual-Marqui
Richard J
RJ
Davidson
D000328:Adult; D000339:Affect / Q000502:physiology; D000704:Analysis of Variance; D001007:Anxiety / Q000523:psychology*; D001921:Brain / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D003863:Depression / Q000523:psychology*; D003866:Depressive Disorder / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000523:psychology; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D011569:Psychiatric Status Rating Scales; D012720:Severity of Illness Index; D014055:Tomography, Emission-Computed