Contribution to a conference proceedings/Journal Article

FZJ-2014-03070

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Are individual responses to theta-burst rTMS in cortical excitability related to changes in motor network connectivity?

Nettekoven, C. (Corresponding Author) ; Volz, L. ; Kutscha, M. ; Eickhoff, S.FZJ* ; Grefkes, C.FZJ*

2014
Thieme Stuttgart [u.a.]

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Please use a persistent id in citations: doi:10.1055/s-0034-1371201

Abstract: Intermittent theta-burst stimulation (iTBS) effectively increases cortical excitability within the human brain (Huang et al., 2005). However, individual after-effects of iTBS vary between subjects, with a large proportion not responding at all in terms of changes in excitability (Ridding and Ziemann, 2010; Hamada et al., 2013). We here investigated whether subjects responding to iTBS show differential changes in resting-state functional connectivity (rsFC) within the cortical motor system compared to subjects with no response.14 healthy, right-handed subjects (m = 7, 27 ± 3 years) received iTBS over the left primary motor cortex (M1) on two days, separated by at least one week. Before and after iTBS-application (i) motor-evoked potentials (MEPs) or (ii) resting-state functional magnetic resonance imaging (fMRI) was assessed. Seed-based whole-brain rsFC was computed for the stimulated M1.Subjects were divided into groups of responders and non-responders according to iTBS-induced changes in MEPs (criterion: increase of at least 10% compared to baseline). Following iTBS, rsFC between M1 and premotor areas was significantly higher in responders compared to both baseline (p ≤0.001, FWE-corrected) and non-responders (p ≤0.001, FWE-corrected). Furthermore, non-responders featured higher levels of pre-interventional rsFC compared to responders (p = 0.061, FWE-corrected). Individual changes in MEPs and rsFC did not correlate.Significant iTBS-induced modulations of rsFC were exclusively found for the group of iTBS-responders, suggesting that changes in cortical excitability and motor network rsFC are related. However, no linear correlation between changes in MEP-amplitudes and rsFC was evident. Furthermore, higher levels of pre-interventional rsFC might prevent iTBS-induced strengthening of premotor-M1 connections, possibly underlying the non-responsiveness to iTBS

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Contributing Institute(s):

1. Kognitive Neurowissenschaften (INM-3)
2. Strukturelle und funktionelle Organisation des Gehirns (INM-1)

Research Program(s):

1. 333 - Pathophysiological Mechanisms of Neurological and Psychiatric Diseases (POF2-333) (POF2-333)
2. 89572 - (Dys-)function and Plasticity (POF2-89572) (POF2-89572)

Appears in the scientific report 2014

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Database coverage:
Current Contents - Clinical Medicine ; JCR ; Nationallizenz ; SCOPUS ; Science Citation Index Expanded ; Thomson Reuters Master Journal List ; Web of Science Core Collection

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