Figure 5.
Findings of significant correlation or regression coefficient between 1H-MRS-measured brain metabolites with each other or other measures in post-traumatic stress disorder (PTSD). Because proton magnetic resonance spectroscopy (1H-MRS) experiments measure multi-functional small molecules in large (>1 cm3) heterogeneous voxels containing many different types of tissue, cell, and associated functional circuitry, correlations between measured metabolite concentrations and anatomical or cognitive measures or clinically relevant variables like symptom reports are useful for interpreting other putative metabolite findings in 1H-MRS studies of disease. The majority of such reported correlations have pertained to clinician-administered PTSD scale (CAPS) indices like arousal, intrusion, symptom re-experience, or total score. Other correlates have included self-reported insomnia indices, magnetic resonance imaging (MRI)-measured brain region volumes, memory performance, and other metabolites, though the latter may also sometimes indicate relationships introduced by quantification method rather than findings of biological significance. *In combined PTSD and control groups including trauma-exposed and/or military veteran individuals; **In combined PTSD and trauma-unmatched control groups. NAA: N-acetyl aspartate; Cr: creatine; mIns: myoinositol; GABA: γ-aminobutyric acid; Glu: glutamate; GSH: glutathione; Cho: total choline; IMI-1: imidazole from histamine, histidine, and homocarnosine.