Cortical blood flow during rest and Wisconsin Card Sorting Test performance in schizophrenia.
BACKGROUND
The aim of this study is to examine if patients with schizophrenia differ in prefrontal, orbitofrontal, temporal, parietal and occipital blood flow from healthy controls during performance of the Wisconsin Card Sorting Test (WCST).


METHODS
We conducted a 99mTc-hexamethylpropylene amine oxime-SPECT study in patients with schizophrenia (n = 21) and in healthy controls (n = 18). The assessment of relative regional cerebral blood flow (relCBF) was achieved by comparing blood flow of well-defined cortical regions to whole brain blood flow. relCBF at rest and during WCST was compared between the groups and in the groups.


RESULTS
Significant bilateral prefrontal and right-sided parietal increases of relCBF were found in patients (p < 0.05) during resting conditions, while prefrontal and parietal interhemispheric asymetry were higher in patients (p < 0.005). However, patients failed to increase right prefrontal and frontobasal relCBF as well as orbitofrontal interhemispheric asymetry during WCST performance in contrast to the control group (p < 0.05). The right occipital relCBF increased significantly in patients only (p < 0.05).


CONCLUSIONS
In our study we could confirm the common hypothesis of schizophrenic hypofrontality at rest and during WCST performance. Moreover, due to our method, we identified significant frontal and parietal interhemispheric asymmetries in schizophrenia at rest as well as right occipital hyperperfusion during WCST.
Ortuño
Felipe
F
University Clinic of Psychiatry, University of Navarra College of Medicine, Pamplona, Spain.
Moreno-Iñiguez
Miguel
M
Millán
Manuel
M
Soutullo
César A
CA
Bonelli
Raphael M
RM
D000328:Adult; D001288:Attention / Q000502:physiology; D001783:Blood Flow Velocity / Q000502:physiology; D002540:Cerebral Cortex / Q000098:blood supply* / Q000000981:diagnostic imaging; D003118:Color Perception / Q000502:physiology*; D004193:Discrimination Learning / Q000502:physiology*; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D005625:Frontal Lobe / Q000098:blood supply / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D010296:Parietal Lobe / Q000098:blood supply / Q000000981:diagnostic imaging; D010364:Pattern Recognition, Visual / Q000502:physiology*; D011340:Problem Solving / Q000502:physiology*; D012039:Regional Blood Flow / Q000502:physiology; D012559:Schizophrenia / Q000000981:diagnostic imaging* / Q000503:physiopathology; D015899:Tomography, Emission-Computed, Single-Photon