Fig 3. Left, The real part of the whole-head ¹H spectra from a male volunteer labeled i.j.a, where "i" (1..3) is the number of the session in the magnet, "j" (1..3) is the number of the back-to-back acquisitions in that session, and a or b indicates the sequence, Fig 2A, -B. Sessions were separated by at least 10 minutes with the subject outside the magnet. Right, Spectra obtained with the same protocol but with the sequence of Fig 2B. Note that both methods yield a whole-brain spectrum, including metabolites other than the NAA. Only the latter, however, is implicitly localized to the brain. mI indicates myo-Inositol; Cho, choline; Cr, creatine; Glu, glutamate.