Mark S. Brown1, Peter Teale2, Dan Collins2, Bryce Pasko2, Debra Singel3, Don C. Rojas2, Martin Reite2
1Radiology, University of Colorado Denver, Aurora, CO, United States; 2Psychiatry, University of Colorado Denver, Aurora, CO, United States; 3Brain Imaging Center, University of Colorado Denver, Aurora, CO, United States
Magnetoencephalography (MEG) recordings of neural oscillations of the gamma band (~40 Hz) phase locking factor (PLF) yield a number that measures how well the response coincides with the stimulus in time. Schizophrenic subjects show impaired tracking ability compared to controls. We have measured the GABA levels in the temporal lobe (auditory cortex) of schizophrenics using J-edited 1H MRS and correlated them with the PLF. Schizophrenics show a negative correlation with PLF compared to the positive correlation exhibited by controls. The results suggest that the impairment is not due to lower levels of GABA, but rather impaired utilization by the schizophrenics.