['Cerebral function impairment remains problematic in subjects with chronic human immunodeficiency virus (HIV) infection despite effective combination antiretroviral therapy (cART). Using cerebral proton magnetic resonance spectroscopy ((1)H MRS), we aimed to determine if abnormalities could be detected in neurologically asymptomatic HIV-infected subjects electively commencing cART.', 'Therapy-naive, HIV-infected individuals and HIV-uninfected controls underwent (1)H MRS in several anatomical voxels including the mid-frontal grey matter (FGM) and right basal ganglia (RBG). Differences in cerebral metabolite ratios between groups and correlations between immune and virological status were assessed.', 'Forty-six subjects were recruited (26 HIV-infected and 20 control subjects). In the HIV-infected group, mean CD4+ count (SD, cells per microlitre) and plasma HIV RNA (SD, log10 copies per millilitre) were 192 (86) and 4.71 (0.64), respectively. Choline (Cho)/Creatine (Cr) and myoinositol (MI)/Cr ratios were significantly lower in the FGM in HIV-infected subjects compared to controls (0.67 (0.14) versus 0.88 (0.49), p\u2009=\u20090.036, and 0.94 (0.28) and 1.17 (0.26), p\u2009=\u20090.008, for Cho/Cr and MI/Cr, respectively) and Cho/Cr ratio associated with CD4+ lymphocyte count (p\u2009=\u20090.041). N-Acetyl-aspartate (NAA)/Cho ratio was significantly lower in the RBG in HIV-infected subjects compared to controls (2.27 (0.54) versus 2.63 (0.68), p\u2009=\u20090.002), and this was associated with greater plasma HIV RNA load (p\u2009=\u20090.014).'] Are two patterns of cerebral metabolite abnormalities detected on proton magnetic resonance spectroscopy in HIV-infected subjects commencing antiretroviral therapy?