Modulation of brain networks during MR-compatible transcranial direct current stimulation
Amber M. Leaver,
Sara Gonzalez,
Megha Vasavada,
Antoni Kubicki,
Mayank Jog,
Danny J.J. Wang,
Roger P. Woods,
Randall Espinoza,
Jacqueline Gollan,
Todd Parrish,
Katherine L. Narr
Affiliations
Amber M. Leaver
Department of Radiology, Northwestern University, Chicago, IL, 60611, United States; Department of Neurology, University of California Los Angeles, Los Angeles, CA, 90095, United States; Corresponding author at: 737N Michigan Ave, Suite 1600, Chicago, IL 60611, United States.
Sara Gonzalez
Department of Neurology, University of California Los Angeles, Los Angeles, CA, 90095, United States
Megha Vasavada
Department of Neurology, University of California Los Angeles, Los Angeles, CA, 90095, United States
Antoni Kubicki
Department of Neurology, University of California Los Angeles, Los Angeles, CA, 90095, United States
Mayank Jog
Department of Neurology, University of California Los Angeles, Los Angeles, CA, 90095, United States
Danny J.J. Wang
Laboratory of FMRI Technology (LOFT), Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, Los Angeles CA 90033, United States
Roger P. Woods
Department of Neurology, University of California Los Angeles, Los Angeles, CA, 90095, United States; Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, CA, 90095, United States
Randall Espinoza
Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, CA, 90095, United States
Jacqueline Gollan
Department of Psychiatry and Behavioral Sciences, Northwestern University, Chicago, IL, 60611, United States
Todd Parrish
Department of Radiology, Northwestern University, Chicago, IL, 60611, United States
Katherine L. Narr
Department of Neurology, University of California Los Angeles, Los Angeles, CA, 90095, United States; Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, CA, 90095, United States
Transcranial direct current stimulation (tDCS) can influence performance on behavioral tasks and improve symptoms of brain conditions. Yet, it remains unclear precisely how tDCS affects brain function and connectivity. Here, we measured changes in functional connectivity (FC) metrics in blood-oxygenation-level-dependent (BOLD) fMRI data acquired during MR-compatible tDCS in a whole-brain analysis with corrections for false discovery rate. Volunteers (n = 64) received active tDCS, sham tDCS, and rest (no stimulation), using one of three previously established electrode tDCS montages targeting left dorsolateral prefrontal cortex (DLPFC, n = 37), lateral temporoparietal area (LTA, n = 16), or superior temporal cortex (STC, n = 11). In brain networks where simulated E field was highest in each montage, connectivity with remote nodes decreased during active tDCS. During active DLPFC-tDCS, connectivity decreased between a fronto-parietal network and subgenual ACC, while during LTA-tDCS connectivity decreased between an auditory-somatomotor network and frontal operculum. Active DLPFC-tDCS was also associated with increased connectivity within an orbitofrontal network overlapping subgenual ACC. Irrespective of montage, FC metrics increased in sensorimotor and attention regions during both active and sham tDCS, which may reflect the cognitive-perceptual demands of tDCS. Taken together, these results indicate that tDCS may have both intended and unintended effects on ongoing brain activity, stressing the importance of including sham, stimulation-absent, and active comparators in basic science and clinical trials of tDCS.
