- Currently taking medications that either have evidence of glutamatergic activity or has previous MRS evidence of effects on brain glutamate levels at the discretion of the PI such as memantine, lamotrigine, lithium, opiates, bupropion, psychostimulants such as amphetamines and methylphenidate, tricyclic antidepressants, benzodiazepines and any other drug that the investigators judge might interfere with the study. (subjects on those medications may still be included in the study however only the values of NAA from MRS will be utilized and not the glutamate measurements).