Theta Burst Stimulation of the Precuneus Modulates Resting State Connectivity in the Left Temporal Pole.
It has been shown that continuous theta burst stimulation (cTBS) over the precuneus acts on specific memory retrieval abilities. In order to study the neural mechanisms beyond these findings, we combined cTBS and resting-state functional magnetic resonance imaging. Our experimental protocol involved stimulation and sham conditions on a group of healthy subjects, and each condition included a baseline and two follow-up acquisitions (5 and 15 min after baseline) after cTBS. We analysed brain functional connectivity by means of graph theoretical measures, with a specific focus on the network modular structure. Our results showed that cTBS of the precuneus selectively affects the left temporal pole, decreasing its functional connectivity in the first follow-up. Moreover, we observed a significant increase in the size of the module of the precuneus in the second follow-up. Such effects were absent in the sham condition. We observed here a modulation of functional connectivity as a result of inhibitory stimulation over the precuneus. Such a modulation first acts indirectly on the temporal area and then extends the connectivity of the precuneus itself by a feed-back mechanism. Our current findings extend our previous behavioural observations and increase our understanding of the mechanisms underlying the stimulation of the precuneus.
['Mancini|Matteo|M|http://orcid.org/0000-0001-7194-4568', 'Mastropasqua|Chiara|C|', 'Bonnì|Sonia|S|', 'Ponzo|Viviana|V|', 'Cercignani|Mara|M|', 'Conforto|Silvia|S|', 'Koch|Giacomo|G|', 'Bozzali|Marco|M|']
D000328:Adult D001921:Brain D005246:Feedback D005260:Female D059907:Functional Neuroimaging D064368:Healthy Volunteers D006801:Humans D008279:Magnetic Resonance Imaging D008297:Male D008568:Memory D009433:Neural Inhibition D009434:Neural Pathways D010296:Parietal Lobe D013702:Temporal Lobe D013826:Theta Rhythm D050781:Transcranial Magnetic Stimulation D055815:Young Adult
Precuneus cTBS Functional connectivity Graph theory TMS fMRI