“…Proton magnetic resonance spectroscopy ( 1 H-MRS) is a safe, noninvasive method for repeated measure of brain GABA and glutamate in human subjects that does not require radioactive tracers or dyes. 1 H-MRS has been applied to the study of GABA and/or glutamate in seizure disorders (Petroff et al, 1995(Petroff et al, , 1996a, major depression (Price et al, 2009;Hasler et al, 2007;Sanacora et al, 1999Sanacora et al, , 2004Auer et al, 2000), anxiety disorders (Hasler et al, 2009;Goddard et al, 2001), premenstrual dysphoric disorder (Epperson et al, 2002), schizophrenia (Kegeles et al, 2012;Marsman et al, 2011), bipolar disorder (Benedetti et al, 2009), nicotine, alcohol, and cocaine addiction (Epperson et al, 2006;Gomez et al, 2011;Licata and Renshaw, 2010) and neurodegenerative diseases such as Parkinson's Disease and Alzheimer's Disease (Griffith et al, 2008). The majority of published in vivo human 1 H-MRS studies have been conducted at fields of 4 Tesla or less and have not included within day or between day reproducibility data for either GABA or glutamate.…”