Thalamic abnormalities in patients with schizophrenia revealed by proton magnetic resonance spectroscopy

Recent investigations suggest that thalamic abnormalities may underlie symp tom formation in schizophrenia. We previously demonstrated reduced concentr ations of N-acetylaspartate (NAA) in tissue from the thalamus of schizophre nic patients using in vitro proton magnetic resonance spectroscopy (H-1-MRS ). In the present study, in vivo H-1-MR spectra of the left thalamus and fr ontal lobe were investigated in 20 patients with schizophrenia and 16 age-m atched control subjects to replicate our previous postmortem findings and s upport the hypothesis of thalamic abnormality in schizophrenia. Schizophren ic patients showed significantly lower NAA/total creatine (Cr) and choline- containing compounds (Cho)/Cr ratios in the thalamus than control subjects, while no significant difference was found in the frontal lobe. There was n o significant correlation in the schizophrenic patients between the NAA/Cr or Cho/Cr ratio and other clinical data including clinical symptoms or neur oleptic dosage. These findings may further support other studies suggesting decreased thalamic volume or neuronal number and/or thalamic dysfunction, and reduction in size of white matter tracts adjacent to the thalamus in sc hizophrenia, as well as our previous postmortem MRS study. (C) 2000 Elsevie r Science Ireland Ltd. All rights reserved.