THE relationship between gamma band response (GBR) and P50 suppression
was investigated among 10 DSM-IV schizophrenia patients and 10 normal
comparison subjects using neuromagnetic and electrical recordings. In
a paired-click paradigm, the neuromagnetic GBR and M100 suppression d
ata improved schizophrenia-normal group separations over the typical e
lectrical, vertex-recorded P50 suppression measure. The neuromagnetic
GBR Tvas also superior to the magnetic equivalent of P50 (M50) for dis
criminating schizophrenia and normal subjects. Our data are consistent
with the hypothesis that P50 may be a subcomponent of the GBR, and th
at P50 suppression may be a proxy for GBR suppression. Measurement of
the GBR should be given consideration as another, and perhaps better,
means for evaluating auditory-evoked response abnormalities among schi
zophrenia patients.