H1-MR-spectroscopy of cerebellum in adult attention deficit/hyperactivity disorder

Introduction: Neurobiological research has implicated the cerebellum as one possible site of neurophysiological dysfunction in ADHD. Latest theoretical conceptualizations of the cerebellum as core site of the brain to model motor as well as cognitive behavior puts further weight to the assumption that it might play a key role in ADHD pathophysiology. Methods: 30 medication free adult ADHD patients and 30 group matched (gender, age and education) healthy controls were investigated using the method of chemical shift imaging (CSI) of the cerebellum. The vermis, left and right cerebellar hemispheres were processed separately. Results: We found significantly increased glutamate-glutamine (Glx) to creatine (Cre) ratios in the left cerebellar hemisphere. No other differences in measured metabolite concentrations were observed. Discussion: To our knowledge this is the first evidence for neurochemical alterations in cerebellar neurochemistry in adult ADHD. They relate well to recent hypotheses that the cerebellum might control mental activities by internal models.