Assessments of function and biochemistry of the anterior cingulate cortex in schizophrenia.
BACKGROUND
Neuroimaging and electrophysiologic studies have consistently provided evidence of impairment in anterior cingulate cortex/medial frontal cortex function in people with schizophrenia. In this study, we sought to clarify the nature of this abnormality by combining proton magnetic resonance spectroscopy (1H-MRS) with functional magnetic resonance imaging (fMRI) at 3T.


METHODS
We used single-voxel MRS acquired in the dorsal anterior cingulate cortex and fMRI during performance of a Stroop color-naming task to investigate the neurochemistry and functional response of the anterior cingulate cortex/medial frontal cortex in 26 stable, medicated subjects with schizophrenia and 23 matched healthy control subjects.


RESULTS
In schizophrenia subjects, we found decreased blood oxygen level-dependent signal in the medial frontal wall, with significant clusters restricted to more dorsal regions compared with healthy subjects. In addition, we observed a trend-level decrease in N-acetylaspartate/creatine (NAA/Cr) levels and a significant positive correlation between NAA/Cr level and the blood oxygen level-dependent signal in schizophrenia subjects that did not exist in healthy subjects. Furthermore, in this group of medicated subjects, we did not find evidence of decreased glutamate + glutamine(Glx)/Cr levels, but there was a significant negative correlation between Glx/Cr levels and negative symptoms.


CONCLUSIONS
Our results suggest that abnormal NAA levels, which may reflect a neuronal dysfunction related to schizophrenia, affect neuronal physiology, as evidenced by reduced blood oxygen level-dependent response.
Reid
Meredith A
MA
Department of Psychiatry and Behavioral Neurobiology, University of Alabama, Birmingham, Alabama 35294-0017, USA.
Stoeckel
Luke E
LE
White
David M
DM
Avsar
Kathy B
KB
Bolding
Mark S
MS
Akella
N Shastry
NS
Knowlton
Robert C
RC
den Hollander
Jan A
JA
Lahti
Adrienne C
AC
D000328:Adult; D000704:Analysis of Variance; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001923:Brain Chemistry; D001931:Brain Mapping; D003401:Creatine / Q000378:metabolism; D005260:Female; D006179:Gyrus Cinguli / Q000098:blood supply / Q000737:chemistry* / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011522:Protons; D011569:Psychiatric Status Rating Scales; D011877:Radionuclide Imaging; D011930:Reaction Time / Q000502:physiology; D012559:Schizophrenia / Q000473:pathology*; D055815:Young Adult
D011522:Protons; D001224:Aspartic Acid; C000179:N-acetylaspartate; D003401:Creatine