Imaging intelligence with proton magnetic resonance spectroscopy

Proton magnetic resonance spectroscopy (1H-MRS) is a technique for the assay of brain neurochemistry in vivo. N-acetylaspartate (NAA), the most prominent metabolite visible within the 1H-MRS spectrum, is found primarily within neurons. The current study was designed to further elucidate NAA–cognition relationships, particularly whether such relationships are moderated by sex, or tissue type (gray or white matter). We administered standard measures of intelligence to 63 young, healthy subjects and obtained spectroscopic imaging data within a slab of tissue superior to the lateral ventricles. We found that lower NAA within right anterior gray matter predicted better performance VIQ (F = 6.83, p = .011, r2 = .10), while higher NAA within the right posterior gray matter region predicted better PIQ (F = 8.175, p = .006, r2 = .12). These findings add to the small but growing body of literature linking brain biochemistry to intelligence in normal healthy subjects using 1H-MRSI.