 Analysis 1: A more finely grained analysis in which the investigators examine the relationship of NAA, Ml and Cho ratios to dorsolateral and striatal subscales after examining their relationship to global cognitive function. The investigators will also study the relationship of the relative concentrations of NAA to Ml NAAMI and Ch NAACh to global and regional subscales. In addition, the preliminary MTR data suggest that there may be laterally effects, which the investigators will examine. 