Modulating spontaneous brain activity using repetitive transcranial magnetic stimulation.
BACKGROUND
When no specific stimulus or task is presented, spontaneous fluctuations in brain activity occur. Brain regions showing such coherent fluctuations are thought to form organized networks known as 'resting-state' networks, a main representation of which is the default mode network. Spontaneous brain activity shows abnormalities in several neurological and psychiatric diseases that may reflect disturbances of ongoing thought processes. Information about the degree to which such spontaneous brain activity can be modulated may prove helpful in the development of treatment options. We investigated the effect of offline low-frequency rTMS on spontaneous neural activity, as measured with fMRI, using a sequential independent-component-analysis and regression approach to investigate local changes within the default mode network.


RESULTS
We show that rTMS applied over the left dorsolateral prefrontal cortex results in distal changes of neural activity, relative to the site of stimulation, and that these changes depend on the patterns of brain network activity during 'resting-state'.


CONCLUSIONS
Whereas the proximal changes may reflect the off-line effect of direct stimulation of neural elements, the distal changes likely reflect modulation of functional connectivity.
Sleep and Cognition, Netherlands Institute for Neurosciences, Royal Netherlands Academy of Arts and Sciences, Meibergdreef 47, Amsterdam, The Netherlands. y.van.der.werf@nin.knaw.nl
Ysbrand D
YD
van der Werf
Ernesto J
EJ
Sanz-Arigita
Sanne
S
Menning
Odile A
OA
van den Heuvel
D000328:Adult; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods*; D058256:Brain Waves / Q000502:physiology*; D018592:Cross-Over Studies; D005071:Evoked Potentials / Q000502:physiology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009415:Nerve Net / Q000502:physiology*; D009434:Neural Pathways / Q000502:physiology; D012044:Regression Analysis; D050781:Transcranial Magnetic Stimulation / Q000379:methods*