Increased short interval intracortical inhibition in participants with previous hamstring strain injury

Abstract Purpose Action observation (AO) during motor imagery (MI), so-called AO + MI, has been proposed as a new form of non-physical training, but the neural mechanisms involved remains largely unknown. Therefore, this study aimed to explore whether there were similarities in the modulation of short-interval intracortical inhibition (SICI) during execution and mental simulation of postural tasks, and if there was a difference in modulation of SICI between AO + MI and AO alone. Method 21 young adults (mean ± SD = 24 ± 6.3 years) were asked to either passively observe (AO) or imagine while observing (AO + MI) or physically perform a stable and an unstable standing task, while motor evoked potentials and SICI were assessed in the soleus muscle. Result SICI results showed a modulation by condition (F2,40 = 6.42, p = 0.009) with less SICI in the execution condition compared to the AO + MI (p = 0.009) and AO (p = 0.002) condition. Moreover, switching from the stable to the unstable stance condition reduced significantly SICI (F1,20 = 8.34, p = 0.009) during both, physically performed (− 38.5%; p = 0.03) and mentally simulated balance (− 10%, p < 0.001, AO + MI and AO taken together). Conclusion The data demonstrate that SICI is reduced when switching from a stable to a more unstable standing task during both real task execution and mental simulation. Therefore, our results strengthen and further support the existence of similarities between executed and mentally simulated actions by showing that not only corticospinal excitability is similarly modulated but also SICI. This proposes that the activity of the inhibitory cortical network during mental simulation of balance tasks resembles the one during physical postural task execution.

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Remote muscle priming anodal transcranial direct current stimulation attenuates short interval intracortical inhibition and increases time to task failure of a constant workload cycling exercise

Experimental Brain Research ◽

10.1007/s00221-021-06103-x ◽

2021 ◽

Author(s):

Simranjit K. Sidhu

Keyword(s):

Direct Current ◽

Transcranial Direct Current Stimulation ◽

Short Interval ◽

Intracortical Inhibition ◽

Cycling Exercise ◽

Task Failure ◽

Direct Current Stimulation

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The Functional Role of Response Suppression during an Urge to Relieve Pain

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_01423 ◽

2019 ◽

Vol 31 (9) ◽

pp. 1404-1421

Author(s):

Kelsey K. Sundby ◽

Johanna Wagner ◽

Adam R. Aron

Keyword(s):

Short Interval ◽

Intracortical Inhibition ◽

Gabaergic Interneuron ◽

Response Suppression ◽

Active Response ◽

Relieve Pain ◽

Clinical Disorders ◽

Functional Relevance ◽

Interneuron Activity

Being in the state of having both a strong impulse to act and a simultaneous need to withhold is commonly described as an “urge.” Although urges are part of everyday life and also important to several clinical disorders, the components of urge are poorly understood. It has been conjectured that withholding an action during urge involves active response suppression. We tested that idea by designing an urge paradigm that required participants to resist an impulse to press a button and gain relief from heat (one hand was poised to press while the other arm had heat stimulation). We first used paired-pulse TMS over motor cortex (M1) to measure corticospinal excitability of the hand that could press for relief, while participants withheld movement. We observed increased short-interval intracortical inhibition, an index of M1 GABAergic interneuron activity that was maintained across seconds and specific to the task-relevant finger. A second experiment replicated this. We next used EEG to better “image” putative cortical signatures of motor suppression and pain. We found increased sensorimotor beta contralateral to the task-relevant hand while participants withheld the movement during heat. We interpret this as further evidence of a motor suppressive process. Additionally, there was beta desynchronization contralateral to the arm with heat, which could reflect a pain signature. Strikingly, participants who “suppressed” more exhibited less of a putative “pain” response. We speculate that, during urge, a suppressive state may have functional relevance for both resisting a prohibited action and for mitigating discomfort.

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Effects of water immersion on short- and long-latency afferent inhibition, short-interval intracortical inhibition, and intracortical facilitation

Clinical Neurophysiology ◽

10.1016/j.clinph.2013.04.008 ◽

2013 ◽

Vol 124 (9) ◽

pp. 1846-1852 ◽

Cited By ~ 11

Author(s):

Daisuke Sato ◽

Koya Yamashiro ◽

Takuya Yoshida ◽

Hideaki Onishi ◽

Yoshimitsu Shimoyama ◽

...

Keyword(s):

Water Immersion ◽

Short Interval ◽

Intracortical Inhibition ◽

Intracortical Facilitation ◽

Afferent Inhibition ◽

Long Latency

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Intracortical Inhibition During Volitional Inhibition of Prepared Action

Journal of Neurophysiology ◽

10.1152/jn.01334.2005 ◽

2006 ◽

Vol 95 (6) ◽

pp. 3371-3383 ◽

Cited By ~ 192

Author(s):

James P. Coxon ◽

Cathy M. Stinear ◽

Winston D. Byblow

Keyword(s):

Primary Motor Cortex ◽

Motor Evoked Potentials ◽

Short Interval ◽

Intracortical Inhibition ◽

Corticomotor Excitability ◽

Hand Muscles ◽

Cortical Level ◽

A Site ◽

Intrinsic Hand Muscles ◽

Inhibitory Networks

Volitional inhibition is the voluntary prevention of a prepared movement. Here we ask whether primary motor cortex (M1) is a site of convergence of cortical activity associated with movement preparation and volitional inhibition. Volitional inhibition was studied by presenting a stop signal before execution of an anticipated response that requires a key lift to intercept a revolving dial. Motor evoked potentials (MEPs) were elicited in intrinsic hand muscles by transcranial magnetic stimulation (TMS) to assess corticomotor excitability and short interval intracortical inhibition (sICI) during task performance. The closer the stop cue was presented to the anticipated response, the harder it was for subjects to inhibit their response. Corticomotor pathway excitability was temporally modulated during volitional inhibition. Using subthreshold TMS, corticomotor excitability was reduced for Stop trials relative to Go trials from 140 ms after the cue. sICI was significantly greater for Stop trials compared with Go trials at a time that preceded the onset of muscle activity associated with the anticipated response. These results provide evidence that volitional inhibition is exerted at a cortical level and that inhibitory networks within M1 contribute to volitional inhibition of prepared action.

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