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Olarogba OB, Lockyer EJ, Antolinez AK, Button DC. Sex-related differences in corticospinal excitability outcome measures of the biceps brachii during a submaximal elbow flexor contraction. Physiol Rep 2024; 12:e16102. [PMID: 39095333 PMCID: PMC11296885 DOI: 10.14814/phy2.16102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Revised: 05/24/2024] [Accepted: 05/24/2024] [Indexed: 08/04/2024] Open
Abstract
The purpose of this study was to investigate the effects of sex, muscle thickness, and subcutaneous fat thickness (SFT) on corticospinal excitability outcome measures of the biceps brachii. Eighteen participants (10 males and 8 females) completed this study. Ultrasound was used to assess biceps brachii muscle thickness and the overlying SFT. Transcranial magnetic stimulation (TMS) was used to determine corticospinal excitability by inducing motor-evoked potentials (MEPs) at eight different TMS intensities from 90% to 160% of active motor threshold (AMT) from the biceps brachii during an isometric contraction of the elbow flexors at 10% of maximum voluntary contraction (MVC). Biceps brachii maximal compound muscle action potential (Mmax) was also recorded prior to and after TMS. Males had higher (p < 0.001) biceps brachii muscle thickness and lower SFT, produced higher levels of MVC force and had, on average, higher (p < 0.001) MEP amplitudes at lower (p < 0.05) percentages of maximal stimulator output than females during the 10% elbow flexion MVC. Multiple linear regression modeling revealed that sex was not associated with any of the neurophysiological parameters examined, while SFT showed a positive association with the stimulation intensity required at AMT (p = 0.035) and a negative association with biceps brachii pre-stimulus electromyography (EMG) activity (p = 0.021). Additionally, there was a small positive association between muscle thickness and biceps brachii pre-stimulus EMG activity (p = 0.049). Overall, this study suggests that some measures of corticospinal excitability may be different between the sexes and influenced by SFT and muscle thickness.
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Affiliation(s)
- Olalekan B. Olarogba
- Human Neurophysiology LabSchool of Human Kinetics and RecreationSt. John'sNewfoundlandCanada
| | - Evan J. Lockyer
- Human Neurophysiology LabSchool of Human Kinetics and RecreationSt. John'sNewfoundlandCanada
- Faculty of MedicineMemorial University of NewfoundlandSt. John'sNewfoundlandCanada
| | - Angie K. Antolinez
- Human Neurophysiology LabSchool of Human Kinetics and RecreationSt. John'sNewfoundlandCanada
| | - Duane C. Button
- Human Neurophysiology LabSchool of Human Kinetics and RecreationSt. John'sNewfoundlandCanada
- Faculty of MedicineMemorial University of NewfoundlandSt. John'sNewfoundlandCanada
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Alizadeh S, Edwards PF, Lockyer EJ, Holmes MWR, Power KE, Behm DG, Button DC. Neuromechanical Differences between Pronated and Supinated Forearm Positions during Upper-Body Wingate Tests. J Sports Sci Med 2024; 23:396-409. [PMID: 38841629 PMCID: PMC11149067 DOI: 10.52082/jssm.2024.396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 05/02/2024] [Indexed: 06/07/2024]
Abstract
Arm-cycling is a versatile exercise modality with applications in both athletic enhancement and rehabilitation, yet the influence of forearm orientation remains understudied. Thus, this study aimed to investigate the impact of forearm position on upper-body arm-cycling Wingate tests. Fourteen adult males (27.3 ± 5.8 years) underwent bilateral assessments of handgrip strength in standing and seated positions, followed by pronated and supinated forward arm-cycling Wingate tests. Electromyography (EMG) was recorded from five upper-extremity muscles, including anterior deltoid, triceps brachii lateral head, biceps brachii, latissimus dorsi, and brachioradialis. Simultaneously, bilateral normal and propulsion forces were measured at the pedal-crank interface. Rate of perceived exertion (RPE), power output, and fatigue index were recorded post-test. The results showed that a pronated forearm position provided significantly (p < 0.05) higher normal and propulsion forces and triceps brachii muscle activation patterns during arm-cycling. No significant difference in RPE was observed between forearm positions (p = 0.17). A positive correlation was found between seated handgrip strength and peak power output during the Wingate test while pronated (dominant: p = 0.01, r = 0.55; non-dominant: p = 0.03, r = 0.49) and supinated (dominant: p = 0.03, r = 0.51; don-dominant: p = 0.04, r = 0.47). Fatigue changed the force and EMG profile during the Wingate test. In conclusion, this study enhances our understanding of forearm position's impact on upper-body Wingate tests. These findings have implications for optimizing training and performance strategies in individuals using arm-cycling for athletic enhancement and rehabilitation.
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Affiliation(s)
- Shahab Alizadeh
- School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
- Department of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Philip F Edwards
- School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
| | - Evan J Lockyer
- School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
- Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada
| | | | - Kevin E Power
- School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
- Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada
| | - David G Behm
- School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
| | - Duane C Button
- School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
- Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada
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Augenstein TE, Oh S, Norris TA, Mekler J, Sethi A, Krishnan C. Corticospinal excitability during motor preparation of upper extremity reaches reflects flexor muscle synergies: A novel principal component-based motor evoked potential analyses. Restor Neurol Neurosci 2024:RNN231367. [PMID: 38607772 DOI: 10.3233/rnn-231367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/14/2024]
Abstract
Background Previous research has shown that noninvasive brain stimulation can be used to study how the central nervous system (CNS) prepares the execution of a motor task. However, these previous studies have been limited to a single muscle or single degree of freedom movements (e.g., wrist flexion). It is currently unclear if the findings of these studies generalize to multi-joint movements involving multiple muscles, which may be influenced by kinematic redundancy and muscle synergies. Objective The objective of this study was to characterize corticospinal excitability during motor preparation in the cortex prior to functional upper extremity reaches. Methods 20 participants without neurological impairments volunteered for this study. During the experiment, the participants reached for a cup in response to a visual "Go Cue". Prior to movement onset, we used transcranial magnetic stimulation (TMS) to stimulate the motor cortex and measured the changes in motor evoked potentials (MEPs) in several upper extremity muscles. We varied each participant's initial arm posture and used a novel synergy-based MEP analysis to examine the effect of muscle coordination on MEPs. Additionally, we varied the timing of the stimulation between the Go Cue and movement onset to examine the time course of motor preparation. Results We found that synergies with strong proximal muscle (shoulder and elbow) components emerged as the stimulation was delivered closer to movement onset, regardless of arm posture, but MEPs in the distal (wrist and finger) muscles were not facilitated. We also found that synergies varied with arm posture in a manner that reflected the muscle coordination of the reach. Conclusions We believe that these findings provide useful insight into the way the CNS plans motor skills.
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Affiliation(s)
- Thomas E Augenstein
- Department of Physical Medicine and Rehabilitation, NeuRRo Lab, Michigan Medicine, Ann Arbor, MI, USA
- Department of Robotics, University of Michigan, Ann Arbor, MI, USA
| | - Seonga Oh
- Department of Physical Medicine and Rehabilitation, NeuRRo Lab, Michigan Medicine, Ann Arbor, MI, USA
| | - Trevor A Norris
- Department of Physical Medicine and Rehabilitation, NeuRRo Lab, Michigan Medicine, Ann Arbor, MI, USA
| | | | - Amit Sethi
- Department of Occupational Therapy, University of Pittsburgh, Pittsburgh, PA, USA
| | - Chandramouli Krishnan
- Department of Physical Medicine and Rehabilitation, NeuRRo Lab, Michigan Medicine, Ann Arbor, MI, USA
- Department of Robotics, University of Michigan, Ann Arbor, MI, USA
- Physical Medicine and Rehabilitation, Michigan Medicine, Ann Arbor, MI, USA
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Crouzier M, Avrillon S, Hug F, Cattagni T. Horizontal foot orientation affects the distribution of neural drive between gastrocnemii during plantarflexion, without changing neural excitability. J Appl Physiol (1985) 2024; 136:786-798. [PMID: 38205551 DOI: 10.1152/japplphysiol.00536.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 12/21/2023] [Accepted: 12/28/2023] [Indexed: 01/12/2024] Open
Abstract
The distribution of activation among muscles from the same anatomical group can be affected by the mechanical constraints of the task, such as limb orientation. For example, the distribution of activation between the gastrocnemius medialis (GM) and lateralis (GL) muscles during submaximal plantarflexion depends on the orientation of the foot in the horizontal plane. The neural mechanisms behind these modulations are not known. The overall aim of this study was to determine whether the excitability of the two gastrocnemius muscles is differentially affected by changes in foot orientation. Nineteen males performed isometric plantarflexions with their foot internally (toes-in) or externally (toes-out) rotated. GM and GL motor unit discharge characteristics were estimated from high-density surface electromyography to estimate neural drive. GM and GL corticospinal excitability and intracortical activity were assessed using transcranial magnetic stimulation through motor-evoked potentials. The efficacy of synaptic transmission between Ia-afferent fibers and α-motoneurons of the GM and GL was evaluated through the Hoffmann reflex. We observed a differential change in neural drive between GM (toes-out > toes-in) and GL (toes-out < toes-in). However, there was no foot orientation-related modulation in corticospinal excitability of the GM or GL, either at the cortical level or through modulation of the efficacy of Ia-α-motoneuron transmission. These results demonstrate that change in the motor pathway excitability is not the mechanism controlling the different distribution of neural drive between GM and GL with foot orientation.NEW & NOTEWORTHY Horizontal foot orientation affects the distribution of neural drive between the gastrocnemii during plantarflexion. There is no foot orientation-related modulation in the corticospinal excitability of the gastrocnemii, either at the cortical level or through modulation of the efficacy of Ia-α-motoneuron transmission. Change in motor pathway excitability is not the mechanism controlling the different distribution of neural drive between gastrocnemius medialis and lateralis with foot orientation.
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Affiliation(s)
- Marion Crouzier
- Nantes University, Movement - Interactions - Performance, MIP, UR-4334, Nantes, France
| | - Simon Avrillon
- Department of Bioengineering, Faculty of Engineering, Imperial College London, London, United Kingdom
| | - François Hug
- Université Côte d'Azur, LAMHESS, Nice, France
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Thomas Cattagni
- Nantes University, Movement - Interactions - Performance, MIP, UR-4334, Nantes, France
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Augenstein TE, Oh S, Norris TA, Mekler J, Sethi A, Krishnan C. Muscle Coordination Matters: Insights into Motor Planning using Corticospinal Responses during Functional Reaching. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.15.540531. [PMID: 37292868 PMCID: PMC10245565 DOI: 10.1101/2023.05.15.540531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The central nervous system (CNS) moves the human body by forming a plan in the primary motor cortex and then executing this plan by activating the relevant muscles. It is possible to study motor planning by using noninvasive brain stimulation techniques to stimulate the motor cortex prior to a movement and examine the evoked responses. Studying the motor planning process can reveal useful information about the CNS, but previous studies have generally been limited to single degree of freedom movements ( e.g., wrist flexion). It is currently unclear if findings in these studies generalize to multi-joint movements, which may be influenced by kinematic redundancy and muscle synergies. Here, our objective was to characterize motor planning in the cortex prior to a functional reach involving the upper extremity. We asked participants to reach for a cup placed in front of them when presented with a visual "Go Cue". Following the go cue, but prior to movement onset, we used transcranial magnetic stimulation (TMS) to stimulate the motor cortex and measured the changes in the magnitudes of evoked responses in several upper extremity muscles (MEPs). We varied each participant's initial arm posture to examine the effect of muscle coordination on MEPs. Additionally, we varied the timing of the stimulation between the go cue and movement onset to examine the time course of changes in the MEPs. We found that the MEPs in all proximal (shoulder and elbow) muscles increased as the stimulation was delivered closer to movement onset, regardless of arm posture, but MEPs in the distal (wrist and finger) muscles were not facilitated or even inhibited. We also found that facilitation varied with arm posture in a manner that reflected the coordination of the subsequent reach. We believe that these findings provide useful insight into the way the CNS plans motor skills.
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Compton CT, Lockyer EJ, Benson RJ, Power KE. Interhemispheric inhibition is different during arm cycling than a position- and intensity-matched tonic contraction. Exp Brain Res 2022; 240:2425-2434. [DOI: 10.1007/s00221-022-06413-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 07/01/2022] [Indexed: 11/29/2022]
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Clos P, Mater A, Legrand H, Poirier G, Ballay Y, Martin A, Lepers R. Corticospinal Excitability Is Lower During Eccentric Than Concentric Cycling in Men. Front Physiol 2022; 13:854824. [PMID: 35370788 PMCID: PMC8966379 DOI: 10.3389/fphys.2022.854824] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 02/14/2022] [Indexed: 11/16/2022] Open
Abstract
How corticospinal excitability changes during eccentric locomotor exercise is unknown. In the present study, 13 volunteers performed 30-min strenuous concentric and eccentric cycling bouts at the same power output (60% concentric peak power output). Transcranial magnetic and electrical femoral nerve stimulations were applied at exercise onset (3rd min) and end (25th min). Motor-evoked potentials (MEPs) amplitude was measured for the rectus femoris (RF) and vastus lateralis (VL) muscles with surface electromyography (EMG) and expressed as a percentage of maximal M-wave amplitude (MMAX). EMG amplitude 100 ms prior to MEPs and the silent period duration were calculated. There was no change in any neural parameter during the exercises (all P > 0.24). VL and RF MMAX were unaffected by exercise modality (all P > 0.38). VL MEP amplitude was greater (26 ± 11.4 vs. 15.2 ± 7.7% MMAX; P = 0.008) during concentric than eccentric cycling whereas RF MEP amplitude was not different (24.4 ± 10.8 vs. 17.2 ± 9.8% MMAX; P = 0.051). While VL EMG was higher during concentric than eccentric cycling (P = 0.03), RF EMG showed no significant difference (P = 0.07). Similar silent period durations were found (RF: 120 ± 30 ms; VL: 114 ± 27 ms; all P > 0.61), but the silent period/MEP ratio was higher during eccentric than concentric cycling for both muscles (all P < 0.02). In conclusion, corticospinal excitability to the knee extensors is lower and relative silent period longer during eccentric than concentric cycling, yet both remained unaltered with time.
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Power KE, Lockyer EJ, Botter A, Vieira T, Button DC. Endurance-exercise training adaptations in spinal motoneurones: potential functional relevance to locomotor output and assessment in humans. Eur J Appl Physiol 2022; 122:1367-1381. [PMID: 35226169 DOI: 10.1007/s00421-022-04918-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 02/11/2022] [Indexed: 12/14/2022]
Abstract
It is clear from non-human animal work that spinal motoneurones undergo endurance training (chronic) and locomotor (acute) related changes in their electrical properties and thus their ability to fire action potentials in response to synaptic input. The functional implications of these changes, however, are speculative. In humans, data suggests that similar chronic and acute changes in motoneurone excitability may occur, though the work is limited due to technical constraints. To examine the potential influence of chronic changes in human motoneurone excitability on the acute changes that occur during locomotor output, we must develop more sophisticated recording techniques or adapt our current methods. In this review, we briefly discuss chronic and acute changes in motoneurone excitability arising from non-human and human work. We then discuss the potential interaction effects of chronic and acute changes in motoneurone excitability and the potential impact on locomotor output. Finally, we discuss the use of high-density surface electromyogram recordings to examine human motor unit firing patterns and thus, indirectly, motoneurone excitability. The assessment of single motor units from high-density recording is mainly limited to tonic motor outputs and minimally dynamic motor output such as postural sway. Adapting this technology for use during locomotor outputs would allow us to gain a better understanding of the potential functional implications of endurance training-induced changes in human motoneurone excitability on motor output.
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Affiliation(s)
- Kevin E Power
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada. .,Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada.
| | - Evan J Lockyer
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada.,Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Alberto Botter
- Laboratory for Engineering of the Neuromuscular System (LISiN), Department of Electronics and Telecommunication, Politecnico di Torino, Turin, Italy.,PoliToBIOMed Lab, Politecnico di Torino, Turin, Italy
| | - Taian Vieira
- Laboratory for Engineering of the Neuromuscular System (LISiN), Department of Electronics and Telecommunication, Politecnico di Torino, Turin, Italy.,PoliToBIOMed Lab, Politecnico di Torino, Turin, Italy
| | - Duane C Button
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada.,Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada
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de Almeida Azevedo R, Jazayeri D, Yeung ST, Khoshreza R, Millet GY, Murias JM, Aboodarda SJ. The effects of pain induced by blood flow occlusion in one leg on exercise tolerance and corticospinal excitability and inhibition of the contralateral leg in males. Appl Physiol Nutr Metab 2022; 47:632-648. [PMID: 35201916 DOI: 10.1139/apnm-2021-0597] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Experiencing pain in one leg can alter exercise tolerance and neuromuscular fatigue (NMF) responses in the contralateral leg; however, the corticospinal modulations to non-local experimental pain induced by blood flow occlusion remain unknown. In three randomized visits, thirteen male participants performed 25% of isometric maximal voluntary contraction (25%IMVC) to task failure with one leg preceded by (i) 6-min rest (CON), (ii) cycling at 80% of peak power output until task failure with the contralateral leg (CYCL) or (iii) CYCL followed by blood flow occlusion (OCCL) during 25%IMVC. NMF assessments (IMVC, voluntary activation [VA] and potentiated twitch [Qtw]) were performed at baseline and task failure. During the 25%IMVC, transcranial magnetic stimulations were performed to obtain motor evoked potential (MEP), silent period (SP), and short intracortical inhibition (SICI). 25%IMVC was shortest in OCCL (105±50s) and shorter in CYCL (154±68s) than CON (219±105s) (P<0.05). IMVC declined less after OCCL (-24±19%) and CYCL (-27±18%) then CON (-35±11%) (P<0.05). Qtw declined less in OCCL (-40±25%) compared to CYCL (-50±22%) and CON (-50±21%) (P<0.05). VA was similar amongst conditions. MEP and SP increased and SICI decreased throughout the task while SP was longer for OCCL compared to CYC condition (P<0.05). The results suggest that pain in one leg diminishes contralateral limb exercise tolerance and NMF development and modulate corticospinal inhibition in males. Novelty: Pain in one leg diminished MVC and twitch force decline in the contralateral limb Experimental pain induced by blood flow occlusion may modulation corticospinal inhibition of the neural circuitries innervating the contralateral exercise limb.
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Affiliation(s)
| | | | | | | | | | - Juan M Murias
- University of Calgary, Faculty of Kinesiology, KNB 434, 2500 University Drive NW, Calgary, Alberta, Canada, T2N1N4;
| | - Saied Jalal Aboodarda
- University of Calgary , Faculty of Kinesiology, 2500 University Drive NW, Calgary, Canada, T2N 1N4;
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Herrero JL, Smith A, Mishra A, Markowitz N, Mehta AD, Bickel S. Inducing neuroplasticity through intracranial θ-burst stimulation in the human sensorimotor cortex. J Neurophysiol 2021; 126:1723-1739. [PMID: 34644179 PMCID: PMC8782667 DOI: 10.1152/jn.00320.2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 09/20/2021] [Accepted: 10/08/2021] [Indexed: 01/04/2023] Open
Abstract
The progress of therapeutic neuromodulation greatly depends on improving stimulation parameters to most efficiently induce neuroplasticity effects. Intermittent θ-burst stimulation (iTBS), a form of electrical stimulation that mimics natural brain activity patterns, has proved to efficiently induce such effects in animal studies and rhythmic transcranial magnetic stimulation studies in humans. However, little is known about the potential neuroplasticity effects of iTBS applied through intracranial electrodes in humans. This study characterizes the physiological effects of intracranial iTBS in humans and compare them with α-frequency stimulation, another frequently used neuromodulatory pattern. We applied these two stimulation patterns to well-defined regions in the sensorimotor cortex, which elicited contralateral hand muscle contractions during clinical mapping, in patients with epilepsy implanted with intracranial electrodes. Treatment effects were evaluated using oscillatory coherence across areas connected to the treatment site, as defined with corticocortical-evoked potentials. Our results show that iTBS increases coherence in the β-frequency band within the sensorimotor network indicating a potential neuroplasticity effect. The effect is specific to the sensorimotor system, the β band, and the stimulation pattern and outlasted the stimulation period by ∼3 min. The effect occurred in four out of seven subjects depending on the buildup of the effect during iTBS treatment and other patterns of oscillatory activity related to ceiling effects within the β band and to preexistent coherence within the α band. By characterizing the neurophysiological effects of iTBS within well-defined cortical networks, we hope to provide an electrophysiological framework that allows clinicians/researchers to optimize brain stimulation protocols which may have translational value.NEW & NOTEWORTHY θ-Burst stimulation (TBS) protocols in transcranial magnetic stimulation studies have shown improved treatment efficacy in a variety of neuropsychiatric disorders. The optimal protocol to induce neuroplasticity in invasive direct electrical stimulation approaches is not known. We report that intracranial TBS applied in human sensorimotor cortex increases local coherence of preexistent β rhythms. The effect is specific to the stimulation frequency and the stimulated network and outlasts the stimulation period by ∼3 min.
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Affiliation(s)
- Jose L Herrero
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, New York
- Department of Neurosurgery, Zucker School of Medicine at Hofstra/Northwell, Manhasset, New York
| | - Alexander Smith
- Department of Neurosurgery, Zucker School of Medicine at Hofstra/Northwell, Manhasset, New York
| | - Akash Mishra
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, New York
- Department of Neurosurgery, Zucker School of Medicine at Hofstra/Northwell, Manhasset, New York
| | - Noah Markowitz
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, New York
- Department of Neurosurgery, Zucker School of Medicine at Hofstra/Northwell, Manhasset, New York
| | - Ashesh D Mehta
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, New York
- Department of Neurosurgery, Zucker School of Medicine at Hofstra/Northwell, Manhasset, New York
| | - Stephan Bickel
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, New York
- Department of Neurosurgery, Zucker School of Medicine at Hofstra/Northwell, Manhasset, New York
- Department of Neurology, Zucker School of Medicine at Hofstra/Northwell, Manhasset, New York
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