scholarly journals Double-Sine-Wave Quadri-Pulse Theta Burst Stimulation of Precentral Motor Hand Representation Induces Bidirectional Changes in Corticomotor Excitability

2021 ◽  
Vol 12 ◽  
Author(s):  
Nikolai H. Jung ◽  
Bernhard Gleich ◽  
Norbert Gattinger ◽  
Anke Kalb ◽  
Julia Fritsch ◽  
...  
Keyword(s):  
Developmental Disorders ◽  
Single Pulse ◽  
Sine Wave ◽  
Corticospinal Excitability ◽  
Precentral Gyrus ◽  
Current Direction ◽  
Induced Current ◽  
Theta Burst Stimulation ◽  
Burst Stimulation ◽  
Theta Burst

Neuronal plasticity is considered to be the neurophysiological correlate of learning and memory and changes in corticospinal excitability play a key role in the normal development of the central nervous system as well as in developmental disorders. In a previous study, it was shown that quadri-pulse theta burst stimulation (qTBS) can induce bidirectional changes in corticospinal excitability (1). There, a quadruple burst consisted of four single-sine-wave (SSW) pulses with a duration of 160 μs and inter-pulse intervals of 1.5 ms to match I-wave periodicity (666 Hz). In the present study, the pulse shape was modified applying double-sine-waves (DSW) rather than SSW pulses, while keeping the pulse duration at 160 μs. In two separate sessions, we reversed the current direction of the DSW pulse, so that its second component elicited either a mainly posterior-to-anterior (DSW PA-qTBS) or anterior-to-posterior (DSW AP-qTBS) directed current in the precentral gyrus. The after-effects of DSW qTBS on corticospinal excitability were examined in healthy individuals (n = 10) with single SSW TMS pulses. For single-pulse SSW TMS, the second component produced the same preferential current direction as DSW qTBS but had a suprathreshold intensity, thus eliciting motor evoked potentials (PA-MEP or AP-MEP). Single-pulse SSW TMS revealed bidirectional changes in corticospinal excitability after DSW qTBS, which depended on the preferentially induced current direction. DSW PA-qTBS at 666 Hz caused a stable increase in PA-MEP, whereas AP-qTBS at 666 Hz induced a transient decrease in AP-MEP. The sign of excitability following DSW qTBS at I-wave periodicity was opposite to the bidirectional changes after SSW qTBS. The results show that the pulse configuration and induced current direction determine the plasticity-effects of ultra-high frequency SSW and DSW qTBS at I-wave periodicity. These findings may offer new opportunities for short non-invasive brain stimulation protocols that are especially suited for stimulation in children and patients with neurological or neurodevelopmental disorders.

scholarly journals Plasticity Induced by Intermittent Theta Burst Stimulation in Bilateral Motor Cortices Is Not Altered in Older Adults

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Daina S. E. Dickins ◽  
Martin V. Sale ◽  
Marc R. Kamke
Keyword(s):  
Older Adults ◽  
Cortical Excitability ◽  
Motor Evoked Potentials ◽  
Single Pulse ◽  
Theta Burst Stimulation ◽  
Burst Stimulation ◽  
Motor Tasks ◽  
Age Related ◽  
Before And After ◽  
Theta Burst

Numerous studies have reported that plasticity induced in the motor cortex by transcranial magnetic stimulation (TMS) is attenuated in older adults. Those investigations, however, have focused solely on the stimulated hemisphere. Compared to young adults, older adults exhibit more widespread activity across bilateral motor cortices during the performance of unilateral motor tasks, suggesting that the manifestation of plasticity might also be altered. To address this question, twenty young (<35 years old) and older adults (>65 years) underwent intermittent theta burst stimulation (iTBS) whilst attending to the hand targeted by the plasticity-inducing procedure. The amplitude of motor evoked potentials (MEPs) elicited by single pulse TMS was used to quantify cortical excitability before and after iTBS. Individual responses to iTBS were highly variable, with half the participants showing an unexpected decrease in cortical excitability. Contrary to predictions, however, there were no age-related differences in the magnitude or manifestation of plasticity across bilateral motor cortices. The findings suggest that advancing age does not influence the capacity for, or manifestation of, plasticity induced by iTBS.

The facilitatory effects of intermittent theta burst stimulation on corticospinal excitability are enhanced by nicotine

2009 ◽  
Vol 120 (8) ◽  
pp. 1610-1615 ◽  
Author(s):  
Orlando B.C. Swayne ◽  
James T.H. Teo ◽  
Richard J. Greenwood ◽  
John C. Rothwell
Keyword(s):  
Corticospinal Excitability ◽  
Theta Burst Stimulation ◽  
Burst Stimulation ◽  
Theta Burst

scholarly journals Sham-derived effects and the minimal reliability of theta burst stimulation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
P. O. Boucher ◽  
R. A. Ozdemir ◽  
D. Momi ◽  
M. J. Burke ◽  
A. Jannati ◽  
...  
Keyword(s):  
Motor Evoked Potentials ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Brain Activity ◽  
Corticospinal Excitability ◽  
Therapeutic Effects ◽  
Theta Burst Stimulation ◽  
Burst Stimulation ◽  
Similar Time ◽  
Repeat Visit ◽  
Theta Burst

AbstractTheta-burst stimulation (TBS) is a patterned form of repetitive transcranial magnetic stimulation (rTMS) that has been used to induce long-term modulation (plasticity) of corticospinal excitability in a drastically shorter duration protocol than conventional rTMS protocols. In this study we tested the reliability of the effects of two well defined TBS protocols, continuous TBS (cTBS) and intermittent TBS (iTBS), especially in relation to sham TBS, within and across the same 24 participants. All TBS protocols were repeated after approximately 1 month to assess the magnitude and reliability of the modulatory effects of each TBS protocol. Baseline and post-TBS changes in motor evoked potentials (MEP—measure of corticospinal excitability) amplitudes were compared across the cTBS, iTBS and sham TBS protocols and between the initial and retest visits. Overall, across participants, at the initial visit, iTBS facilitated MEPs as compared to baseline excitability, with sham eliciting the same effect. cTBS did not show a significant suppression of excitability compared to baseline MEPs at either visit, and even facilitated MEPs above baseline excitability at a single time point during the repeat visit. Otherwise, effects of TBS were generally diminished in the repeat visit, with iTBS and sham TBS replicating facilitation of MEPs above baseline excitability at similar time points. However, no protocol demonstrated consistent intra-individual modulation of corticospinal excitability upon retest. As the first study to test both iTBS and cTBS against sham TBS across repeat visits, our findings challenge the efficacy and reliability of TBS protocols and emphasize the importance of accounting for sham effects of TBS. Furthermore, given that therapeutic effects of TBS are hypothetically derived from consistent and repeated modulation of brain activity, the non-replicability of plasticity and sham effects call into question these basic mechanisms.

scholarly journals Facilitation of Motor Evoked Potentials in Response to a Modified 30 Hz Intermittent Theta-Burst Stimulation Protocol in Healthy Adults

2021 ◽  
Vol 11 (12) ◽  
pp. 1640
Author(s):  
Katarina Hosel ◽  
François Tremblay
Keyword(s):  
Evoked Potentials ◽  
Motor Evoked Potentials ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Single Pulse ◽  
Theta Burst Stimulation ◽  
Stimulation Protocol ◽  
Burst Stimulation ◽  
Theta Burst ◽  
Posterior Anterior ◽  
Anterior Posterior

Theta-burst stimulation (TBS) is a form of repetitive transcranial magnetic stimulation (rTMS) developed to induce neuroplasticity. TBS usually consists of 50 Hz bursts at 5 Hz intervals. It can facilitate motor evoked potentials (MEPs) when applied intermittently, although this effect can vary between individuals. Here, we sought to determine whether a modified version of intermittent TBS (iTBS) consisting of 30 Hz bursts repeated at 6 Hz intervals would lead to lasting MEP facilitation. We also investigated whether recruitment of early and late indirect waves (I-waves) would predict individual responses to 30 Hz iTBS. Participants (n = 19) underwent single-pulse TMS to assess MEP amplitude at baseline and variations in MEP latency in response to anterior-posterior, posterior-anterior, and latero-medial stimulation. Then, 30 Hz iTBS was administered, and MEP amplitude was reassessed at 5-, 20- and 45-min. Post iTBS, most participants (13/19) exhibited MEP facilitation, with significant effects detected at 20- and 45-min. Contrary to previous evidence, recruitment of early I-waves predicted facilitation to 30 Hz iTBS. These observations suggest that 30 Hz/6 Hz iTBS is effective in inducing lasting facilitation in corticospinal excitability and may offer an alternative to the standard 50 Hz/5 Hz protocol.

scholarly journals Reversed Effects of Intermittent Theta Burst Stimulation following Motor Training That Vary as a Function of Training-Induced Changes in Corticospinal Excitability

2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Tino Stöckel ◽  
Jeffery J. Summers ◽  
Mark R. Hinder
Keyword(s):  
Motor Learning ◽  
Sham Group ◽  
Group Performance ◽  
Motor Task ◽  
Corticospinal Excitability ◽  
Theta Burst Stimulation ◽  
Burst Stimulation ◽  
Before And After ◽  
And Performance ◽  
Theta Burst

Intermittent theta burst stimulation (iTBS) has the potential to enhance corticospinal excitability (CSE) and subsequent motor learning. However, the effects of iTBS following motor learning are unknown. The purpose of the present study was to explore the effect of iTBS on CSE and performance following motor learning. Therefore twenty-four healthy participants practiced a ballistic motor task for a total of 150 movements. iTBS was subsequently applied to the trained motor cortex (STIM group) or the vertex (SHAM group). Performance and CSE were assessed before motor learning and before and after iTBS. Training significantly increased performance and CSE in both groups. In STIM group participants, subsequent iTBS significantly reduced motor performance with smaller reductions in CSE. CSE changes as a result of motor learning were negatively correlated with both the CSE changes and performance changes as a result of iTBS. No significant effects of iTBS were found for SHAM group participants. We conclude that iTBS has the potential to degrade prior motor learning as a function of training-induced CSE changes. That means the expected LTP-like effects of iTBS are reversed following motor learning.

Phasic Voluntary Movements Reverse the Aftereffects of Subsequent Theta-Burst Stimulation in Humans

2008 ◽  
Vol 100 (4) ◽  
pp. 2070-2076 ◽  
Author(s):  
Ennio Iezzi ◽  
Antonella Conte ◽  
Antonio Suppa ◽  
Rocco Agostino ◽  
Loredana Dinapoli ◽  
...  
Keyword(s):  
Primary Motor Cortex ◽  
Motor Evoked Potentials ◽  
Single Pulse ◽  
Mean Amplitude ◽  
Voluntary Movements ◽  
Finger Movements ◽  
Theta Burst Stimulation ◽  
Burst Stimulation ◽  
Healthy Humans ◽  
Theta Burst

Theta-burst stimulation (TBS) is a technique that elicits long-lasting changes in the excitability of human primary motor cortex (M1). Tonic contraction of the target muscle modifies the aftereffects of TBS, whereas interactions between phasic muscle contraction and the aftereffects of TBS are unknown. In this paper, we investigated whether phasic voluntary movements influence TBS-induced changes in M1 excitability. We examined whether a brief sequence of phasic finger movements performed by healthy humans before both intermittent TBS (iTBS) and continuous TBS (cTBS) influences TBS-induced aftereffects. Ten healthy subjects underwent iTBS and cTBS. To evaluate the TBS-induced aftereffects on M1 excitability, single TMS pulses were given over the FDI motor area before (T0) and 5 (T1), 15 (T2), and 30 min (T3) after TBS. To find out whether finger movements influenced the TBS-induced aftereffects, we tested motor-evoked potentials (MEPs) size by single TMS pulses at T0, immediately after movements, and at T1–T3. We also measured the kinematic variables mean amplitude and mean peak velocity of the movements. When no phasic voluntary movements preceded TBS, iTBS elicited facilitatory and cTBS elicited inhibitory aftereffects on MEP size. Conversely, movements performed before TBS elicited significant changes in the direction of the TBS-induced aftereffects. iTBS produced inhibitory instead of facilitatory aftereffects and cTBS produced facilitatory instead of inhibitory aftereffects. Finger movements alone had no effects on MEPs size tested with single-pulse TMS. Peripheral electrical stimulation had no effect on iTBS-induced aftereffects. Repeated phasic finger movements interfere with TBS-induced aftereffects probably by modulating mechanisms of brain metaplasticity.

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