title: Involvement of glutamate in rest-stimulus interaction between perigenual and supragenual anterior cingulate cortex: a combined fMRI-MRS study.
abstract: The brain shows a high degree of activity at rest. The significance of this activity has come increasingly into focus. At present, however, the interaction between this activity and stimulus-induced activity is not well defined. The interaction between a task-negative (perigenual anterior cingulate cortex, pgACC) and task-positive (supragenual anterior cingulate cortex, sgACC) region during a simple task was thus investigated using a combination of fMRI and MRS. Negative BOLD responses in the pgACC were found to show a unidirectional effective connectivity with task-induced positive BOLD responses in the sgACC. This connectivity was shown to be related specifically with glutamate levels in the pgACC. These results demonstrate an interaction between deactivation from resting-state and resting-state glutamate levels in a task-negative region (pgACC), and task-induced activity in a task-positive region (sgACC). This provides insight into the neuronal and biochemical mechanisms by means of which the resting state activity of the brain potentially impacts upon subsequent stimulus-induced activity.
authors.affiliation: Mind, Brain Imaging and Neuroethics, Institute of Mental Health Research, University of Ottawa, Ottawa, ON, Canada.
authors.forename: Niall W
authors.initials: NW
authors.lastname: Duncan
authors.forename: Björn
authors.initials: B
authors.lastname: Enzi
authors.forename: Christine
authors.initials: C
authors.lastname: Wiebking
authors.forename: Georg
authors.initials: G
authors.lastname: Northoff
mesh_terms: D000328:Adult; D001931:Brain Mapping / Q000379:methods*; D005260:Female; D018698:Glutamic Acid / Q000378:metabolism*; D006179:Gyrus Cinguli / Q000378:metabolism*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D009434:Neural Pathways / Q000502:physiology*; D012146:Rest / Q000502:physiology*; D055815:Young Adult
chemical_list: D018698:Glutamic Acid