Psychotic symptoms in major depressive disorder are associated with reduced regional cerebral blood flow in the subgenual anterior cingulate cortex: a voxel-based single photon emission computed tomography (SPECT) study.
BACKGROUND
Delusions and/or hallucinations are not an uncommon feature in severe major depressive episodes. Functional imaging studies of depression have been widely reported in the literature, but few of these have attempted to investigate the neurophysiological correlates of psychotic symptoms.


METHODS
We measured resting regional cerebral blood flow (rCBF) with the (99m)Tc-ECD SPECT technique in patients with major depressive disorder with (n=9) and without (n=12) psychotic features, as well as in a group of healthy volunteers (n=12). Between-group rCBF comparisons were performed using the voxel-based statistical parametric mapping method.


RESULTS
Major depressed patients with psychotic features showed decreased rCBF in the left subgenual anterior cingulate cortex relative to both non-psychotic patients and healthy controls (P<0.001 one-tailed, uncorrected for multiple comparisons). Relative to the non-psychotic group, depressed patients with psychotic symptoms also had a focus of decreased rCBF in the right inferior frontal cortex, with the voxel of maximal significance in the insula (P<0.031, corrected for multiple comparisons). A similar pattern of significant between-group rCBF differences between psychotic and non-psychotic patients emerged after covarying the analysis for the confounding influence of overall illness severity.


CONCLUSIONS
These results provide preliminary evidence that psychotic symptoms in major depression may be associated with abnormalities in ventral paralimbic regions previously implicated in mood regulation and depression.
Skaf
Cesar R
CR
Department of Psychiatry, University of São Paulo Medical School, São Paulo, Brazil. skaf@netpar.com.br
Yamada
Airton
A
Garrido
Griselda E J
GE
Buchpiguel
Carlos A
CA
Akamine
Sergio
S
Castro
Claudio C
CC
Busatto
Geraldo F
GF
D000328:Adult; D000339:Affect / Q000502:physiology; D001931:Brain Mapping; D003865:Major Depressive Disorder / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000523:psychology; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D006179:Gyrus Cinguli / Q000098:blood supply* / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D011618:Psychotic Disorders / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000523:psychology; D012039:Regional Blood Flow / Q000502:physiology; D015899:Tomography, Emission-Computed, Single-Photon