Symptom profiles in schizophrenia consists of positive and negative symptom dimensions which
are considered to be related to different underlying pathophysiologies and neural substrates. The
purpose of the study was to identify the possible relationship between relative regional cerebral
perfusion and positive and negative symptom dimension in unmedicated patients with schizophrenia.
Twenty-seven unmedicated patients with schizophrenia(13 patients who were antipsychotic drugnaive and 14 patients who had been drug-free for at least 1 week) were included in the study. Regional
cerebral perfusion was studied with the single-photon emission computed tomography(SPECT).
Symptom dimensions were assessed with positive and negative syndrome scale(PANSS).
The scores of each symptom dimension were correlated with regional cerebral perfusion. The
results were 1) positive symptom dimension score was significantly related to decreased perfusion in
the medial temporal lobe and increased perfusion in the frontal lobe, 2) negative symptom dimension
score was significantly related to decreased perfusion in the basal ganglia, thalamus and increased
perfusion in the frontal lobe.
These results suggest that positive symptom dimension is associated with the dysfunction of the
link between the frontal lobe and the medial temporal lobe and that negative symptom dimension is
related with the impairment of frontal-basal ganglia circuit.