Lars Michels1, Ernst Martin1,
Peter Klaver2, Richard Edden3, Daniel Brandeis4,
Rafael Lchinger4, David Lythgoe5, Fernando Zelaya5,
Ruth L. O'Gorman1
1University Children's
Hospital, Zrich, Switzerland; 2Department of Psychology,
University of Zrich, Zrich, Switzerland; 3Russell H Morgan
Department of Radiology & Radiological Sciences, Johns Hopkins
University, Baltimore, MD, United States; 4Department of Child
& Adolescent Psychiatry, University of Zrich, Zrich, Switzerland; 5Centre
for Neuroimaging Sciences, Institute of Psychiatry, London, United Kingdom
Recent studies have uncovered a link between resting GABA levels and resting perfusion, BOLD, and changes in cerebral blood volume during stimulation, but the relationship between neurotransmitter and haemodynamic activity during cognition is unknown. This study investigates whether modulations in GABA and glutamate can be detected during working memory (WM) and whether these neurotransmitter changes correlate with perfusion measures. GABA levels increased significantly during the first WM task and then decreased across subsequent task runs. Resting GABA levels correlated inversely to the change in perfusion during WM, and the change in Glx during WM correlated inversely with the resting perfusion.