MRS methods to distinguish Glu from Gln require specialized spectral acquisition and editing (e.g., Choi et al., 2006; Schubert, Gallinat, Seifert, & Rinneberg, 2004). In reviewing the MRS-literature on the in vivo detection of glutamate metabolism changes in alcoholism, whether Glx, Glu, or Gln were measured is indicated. An important consideration is that MRS methods cannot distinguish between intracellular and extracellular pools of glutamate and thus the relevance of changes in glutamate levels can be difficult to interpret.
