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Pearcey GEP, Zehr EP. Repeated and patterned stimulation of cutaneous reflex pathways amplifies spinal cord excitability. J Neurophysiol 2020; 124:342-351. [PMID: 32579412 DOI: 10.1152/jn.00072.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Priming with patterned stimulation of antagonist muscle afferents induces modulation of spinal cord excitability as evidenced by changes in group Ia reciprocal inhibition. When assessed transiently with a condition-test pulse paradigm, stimulating cutaneous afferents innervating the foot reduces Ia presynaptic inhibition and facilitates soleus Hoffmann (H)-reflex amplitudes. Modulatory effects (i.e., priming) of longer lasting sensory stimulation of cutaneous afferents innervating the foot have yet to be examined. As a first step, we examined how priming with 20 min of patterned and alternating stimulation between the left and right foot affects spinal cord excitability. During priming, stimulus trains (550 ms; consisting of twenty-eight 1-ms pulses at 51 Hz, 1.2 times the radiating threshold) were applied simultaneously to the sural and plantar nerves of the ankle. Stimulation to the left and right ankle was out of phase by 500 ms. We evoked soleus H-reflexes and muscle compound action potentials (M waves) before and following priming stimulation to provide a proxy measure of spinal cord excitability. H-reflex and M-wave recruitment curves were recorded at rest, during brief (<2 min) arm cycling, and with sural conditioning [train of five 1-ms pulses at 2 times the radiating threshold (RT) with a condition-test interval (C-T) = 80 ms]. Data indicate an increase in H-reflex excitability following priming via patterned sensory stimulation. Transient sural conditioning was less effective following priming, indicating that the increased excitability of the H-reflex is partially attributable to reductions in group Ia presynaptic inhibition. Sensory stimulation to cutaneous afferents, which enhances spinal cord excitability, may prove useful in both rehabilitation and performance settings.NEW & NOTEWORTHY Priming via patterned stimulation of the nervous system induces neuroplasticity. Yet, accessing previously known cutaneous reflex pathways to alter muscle reflex excitability has not yet been examined. Here, we show that sensory stimulation of the cutaneous afferents that innervate the foot sole can amplify spinal cord excitability, which, in this case, is attributed to reductions in presynaptic inhibition.
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Affiliation(s)
- Gregory E P Pearcey
- Rehabilitation Neuroscience Laboratory, University of Victoria, Victoria, British Columbia, Canada.,Human Discovery Science, International Collaboration on Repair Discoveries (ICORD), Vancouver, British Columbia, Canada.,Centre for Biomedical Research, University of Victoria, Victoria, British Columbia, Canada
| | - E Paul Zehr
- Rehabilitation Neuroscience Laboratory, University of Victoria, Victoria, British Columbia, Canada.,Human Discovery Science, International Collaboration on Repair Discoveries (ICORD), Vancouver, British Columbia, Canada.,Centre for Biomedical Research, University of Victoria, Victoria, British Columbia, Canada.,Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
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Serrano-Muñoz D, Gómez-Soriano J, Bravo-Esteban E, Ávila-Martín G, Galán-Arriero I, Taylor J, Avendaño-Coy J. Soleus H-reflex modulation following transcutaneous high- and low-frequency spinal stimulation in healthy volunteers. J Electromyogr Kinesiol 2019; 46:1-7. [DOI: 10.1016/j.jelekin.2019.03.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 03/04/2019] [Accepted: 03/06/2019] [Indexed: 12/22/2022] Open
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Ansari Y, Remaud A, Tremblay F. Variations in corticomotor excitability in response to distal focal thermal stimulation. Somatosens Mot Res 2018; 35:69-79. [DOI: 10.1080/08990220.2018.1460263] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Yekta Ansari
- School of Rehabilitation Sciences, Faculty of Health Sciences, University of Ottawa, Ottawa, ON, Canada
| | - Anthony Remaud
- Clinical Neuroscience Laboratory, Bruyère Research Institute, Ottawa, ON, Canada
| | - François Tremblay
- School of Rehabilitation Sciences, Faculty of Health Sciences, University of Ottawa, Ottawa, ON, Canada
- Clinical Neuroscience Laboratory, Bruyère Research Institute, Ottawa, ON, Canada
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Serrano-Muñoz D, Gómez-Soriano J, Bravo-Esteban E, Vázquez-Fariñas M, Taylor J, Avendaño-Coy J. Intensity matters: Therapist-dependent dose of spinal transcutaneous electrical nerve stimulation. PLoS One 2017; 12:e0189734. [PMID: 29244850 PMCID: PMC5731687 DOI: 10.1371/journal.pone.0189734] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 11/30/2017] [Indexed: 11/18/2022] Open
Abstract
The intensity used during transcutaneous electrical nerve stimulation (TENS) in both, clinical practice and research studies, is often based on subjective commands such as “strong but comfortable sensation”. There is no consensus regarding the effectiveness dose of TENS. The objective was to determine the difference in the effect of spinal TENS on soleus H-reflex modulation when applied by two therapists instructed to apply the stimulation at a “strong but comfortable” intensity. Twenty healthy volunteers divided into two groups: Therapist 1 (n = 10) and Therapist 2 (n = 10). Both therapist applied spinal TENS and sham stimulation at the T10–12 spinal level for 40min in random order to each subject, at an intensity designed to produce a “strong but comfortable” sensation. To avoid habituation, the intensity was adjusted every 2min. Soleus H-reflex was recorded before, during, and 10min after TENS by an observer blinded to the stimulus applied. Despite the instruction to apply TENS at a “strong comfortable” level, a significant difference in current density was identified: Therapist 1 (0.67mA/cm2, SD 0.54) applied more than Therapist 2 (0.53mA/cm2, SD 0.57; p<0.001) at the onset of the intervention. Maximal peak-to-peak H-reflex amplitude was inhibited significantly more 10min following TENS applied by Therapist 1 (-0.15mV, SD 0.16) compared with Therapist 2 (0.04mV, SD 0.16; p = 0.03). Furthermore, current density significantly correlated with the inhibitory effect on peak-to-peak Soleus H-reflex amplitude 10 min after stimulation (Rho = -0.38; p = 0.04). TENS intensity dosage by the therapist based on the subjective perception of the participants alone is unreliable and requires objective standardization. In addition, higher current density TENS produced greater inhibition of the Soleus H-reflex.
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Affiliation(s)
- Diego Serrano-Muñoz
- Sensorimotor Function Group, Hospital Nacional de Parapléjicos, Toledo, Spain
| | - Julio Gómez-Soriano
- Toledo Physiotherapy Research Group (GIFTO), Nursing and Physiotherapy School, Castilla La Mancha University, Toledo, Spain
- * E-mail:
| | - Elisabeth Bravo-Esteban
- Toledo Physiotherapy Research Group (GIFTO), Nursing and Physiotherapy School, Castilla La Mancha University, Toledo, Spain
| | | | - Julian Taylor
- Sensorimotor Function Group, Hospital Nacional de Parapléjicos, Toledo, Spain
- Stoke Mandeville Spinal Research, National Spinal Injuries Centre, Buckinghamshire Healthcare Trust, NHS, Aylesbury, United Kingdom
- Harris Manchester College, University of Oxford, Oxford, United Kingdom
| | - Juan Avendaño-Coy
- Toledo Physiotherapy Research Group (GIFTO), Nursing and Physiotherapy School, Castilla La Mancha University, Toledo, Spain
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Koyama S, Tanabe S, Ishikawa T, Itoh S, Kubota S, Sakurai H, Kanada Y. Time-dependent effects of neuromuscular electrical stimulation on changes in spinal excitability are dependent on stimulation frequency: A preliminary study in healthy adults. Somatosens Mot Res 2014; 31:221-6. [DOI: 10.3109/08990220.2014.931279] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Effect of repetitive afferent electrical stimulation of the lower limb on corticomotor excitability and implications for rehabilitation. J Clin Neurosci 2013; 20:435-9. [DOI: 10.1016/j.jocn.2012.02.049] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Revised: 02/08/2012] [Accepted: 02/14/2012] [Indexed: 11/24/2022]
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Hirose H, Suzuki T, Shimada T. Excitability of Spinal Motor Neuron Function after the Transcutaneous Electrical Stimulation (TES) in Healthy Subjects -F-wave Study. JOURNAL OF THE JAPANESE PHYSICAL THERAPY ASSOCIATION 2006; 9:17-20. [PMID: 25792946 DOI: 10.1298/jjpta.9.17] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2005] [Accepted: 11/26/2005] [Indexed: 11/23/2022]
Abstract
To clarify the excitability of spinal motor neuron function after transcutaneous electrical stimulation (TES), we investigated the F-wave before and after TES. Fourteen healthy volunteers with a mean age of 23.4 years were studied. TES was applied to the flexor hallucis brevis (FHB) for 15 minutes. F-wave and M-wave were recorded from the FHB after tibial nerve stimulation at the ankle before TES, just after TES, 10, 20 and 30 minutes after TES. TES evoked full flexion of the great toe. F-wave was analyzed for the amplitude ratio of F/M, latency and duration. The amplitude ratio of F/ M was 3.1% before TES, 1.4% just after TES, 1.6% 10 minutes after, 1.9% 20 minutes after and 1.7% 30 minutes after TES. Each amplitude ratio of F/M after TES was significantly lower than that before TES (p<0.05). There was no statistically significant difference in the latency and the duration. These results suggest that the excitability of spinal motor neuron function after TES to muscles under this condition was reduced in healthy subjects.
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Affiliation(s)
- Hiroaki Hirose
- Department of Physical Therapy, Kansai Vocational College of Medicine, Osaka 558-0011, Japan
| | - Toshiaki Suzuki
- Research Center of Neurological Diseases, Kansai College of Oriental Medicine, Osaka 590-0482, Japan
| | - Tomoaki Shimada
- Division of Health Sciences, Kobe University Graduate School of Medicine, Hyogo 654-0142, Japan
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Dickstein R, Laufer Y, Katz M. TENS to the posterior aspect of the legs decreases postural sway during stance. Neurosci Lett 2006; 393:51-5. [PMID: 16207512 DOI: 10.1016/j.neulet.2005.09.039] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2005] [Revised: 09/13/2005] [Accepted: 09/15/2005] [Indexed: 10/25/2022]
Abstract
The purpose of this study was to examine the effect of Transcutaneous Electrical Nerve Stimulation (TENS) applied to the posterior aspect of the legs, on postural sway during stance. Thirty healthy subjects were tested while standing on a force platform under four stimulation conditions: no TENS, bilateral TENS, and unilateral left and right TENS. Thirty-second long tests, employing detection threshold amplitudes, were performed in three blocks. In each block, the four conditions were applied both with and without vision in a random order. The results indicate that the application of TENS brought about a decrease in postural sway as expressed by average sway velocity, in addition to a decrease in the absolute values of maximal and minimal medio-lateral and anterior-posterior velocity. Thus, similar to sub-threshold random electrical noise, it appears that the application of low-amplitude TENS to the lower limbs decreases postural sway during stance. Considering the ease of TENS application and the high prevalence of postural disorders, the potential clinical significance of this observation is to be determined by further studies.
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Affiliation(s)
- Ruth Dickstein
- Department of Physical Therapy, Faculty of Social Welfare and Health Studies, University of Haifa, Mount Carmel, Israel.
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Miller L, Mattison P, Paul L, Wood L. The effects of transcutaneous electrical nerve stimulation on spasticity. PHYSICAL THERAPY REVIEWS 2005. [DOI: 10.1179/108331905x68565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Tinazzi M, Zarattini S, Valeriani M, Romito S, Farina S, Moretto G, Smania N, Fiaschi A, Abbruzzese G. Long-lasting modulation of human motor cortex following prolonged transcutaneous electrical nerve stimulation (TENS) of forearm muscles: evidence of reciprocal inhibition and facilitation. Exp Brain Res 2004; 161:457-64. [PMID: 15551083 DOI: 10.1007/s00221-004-2091-y] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2004] [Accepted: 07/30/2004] [Indexed: 12/19/2022]
Abstract
Several lines of evidence indicate that motor cortex excitability can be modulated by manipulation of afferent inputs, like peripheral electrical stimulation. Most studies in humans mainly dealt with the effects of prolonged low-frequency peripheral nerve stimulation on motor cortical excitability, despite its being known from animal studies that high-frequency stimulation can also result in changes of the cortical excitability. To investigate the possible effects of high-frequency peripheral stimulation on motor cortical excitability we recorded motor-evoked potentials (MEPs) to transcranial magnetic stimulation (TMS) of the left motor cortex from the right flexor carpi radialis (FCR), extensor carpi radialis (ECR), and first dorsal interosseous (FDI) in normal subjects, before and after transcutaneous electrical nerve stimulation (TENS) of 30 min duration applied over the FCR. The amplitude of MEPs from the FRC was significantly reduced from 10 to 35 min after TENS while the amplitude of MEPs from ECR was increased. No effects were observed in the FDI muscle. Indices of peripheral nerve (M-wave) and spinal cord excitability (H waves) did not change throughout the experiment. Electrical stimulation of the lateral antebrachial cutaneous nerve has no significant effect on motor cortex excitability. These findings suggest that TENS of forearm muscles can induce transient reciprocal inhibitory and facilitatory changes in corticomotoneuronal excitability of forearm flexor and extensor muscles lasting several minutes. These changes probably may occur at cortical site and seem to be mainly dependent on stimulation of muscle afferents. These findings might eventually lead to practical applications in rehabilitation, especially in those syndromes in which the excitatory and inhibitory balance between agonist and antagonist is severely impaired, such as spasticity and dystonia.
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Affiliation(s)
- Michele Tinazzi
- Unità Operativa Neurologia, Ospedale Civile Borgo Trento, Piazzale Stefani 1, 37100 Verona, Italy.
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Mima T, Oga T, Rothwell J, Satow T, Yamamoto JI, Toma K, Fukuyama H, Shibasaki H, Nagamine T. Short-term high-frequency transcutaneous electrical nerve stimulation decreases human motor cortex excitability. Neurosci Lett 2004; 355:85-8. [PMID: 14729241 DOI: 10.1016/j.neulet.2003.10.045] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Several previous studies have shown that periods of changed sensory input can have after effects on the excitability of the corticospinal system. Here we test whether the parameters of peripheral stimulation conventionally used to treat pain with transcutaneous electrical nerve stimulation (TENS: 90 Hz) also have modulatory effects on the motor system. We measured the amplitude of motor evoked potentials (MEPs) elicited by the focal transcranial magnetic stimulation in the right abductor pollicis brevis and first dorsal interosseous muscles before and after 30 min TENS over the right thenar eminence. In addition, we evaluated tactile and 2-point discrimination thresholds at the same site. TENS transiently reduced MEPs and increased sensory thresholds. This suggests that short-term TENS might have an inhibitory effect on both the sensory and motor systems.
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Affiliation(s)
- Tatsuya Mima
- Human Brain Research Center, Kyoto University Graduate School of Medicine, Human and Brain Research Center, Kyoto 606-8507, Japan.
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McDonnell M, Warden-Flood A. Effect of partial foot anaesthesia on normal gait. THE AUSTRALIAN JOURNAL OF PHYSIOTHERAPY 2001; 46:115-120. [PMID: 11676795 DOI: 10.1016/s0004-9514(14)60319-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The role of cutaneous sensation during gait is controversial. Hence this double-blind study investigated the effect of partial foot anaesthesia on gait velocity. Twenty healthy female subjects were randomly allocated to treatment or control groups. Velocity was determined from three walking trials over a compliant foam walkway. Eutectic Mixture of Local Anaesthetics (EMLA) or Vitamin E Cream was applied to the undersurface of the feet of subjects in treatment or control groups respectively. All subjects rested in sitting for 60 minutes and gait was reassessed. Mean velocity significantly decreased by 6.06m/min following EMLA, which suggests that cutaneous input is important for gait in less predictable environments, and that loss of cutaneous sensation may contribute to gait deficits.
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Affiliation(s)
- Michelle McDonnell
- School of Physiotherapy, University of South Australia, Adelaide, SA, 5000, Australia.
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Walsh DM, Noble G, Baxter GD, Allen JM. Study of the effects of various transcutaneous electrical nerve stimulation (TENS) parameters upon the RIII nociceptive and H-reflexes in humans. CLINICAL PHYSIOLOGY (OXFORD, ENGLAND) 2000; 20:191-9. [PMID: 10792412 DOI: 10.1046/j.1365-2281.2000.00246.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Despite over two decades of clinical use, the neurophysiological and anti-nociceptive effects of transcutaneous electrical nerve stimulation (TENS) have yet to be definitively described. The current study was designed to examine the effect of TENS on the RIII nociceptive reflex elicited in healthy human subjects; the H-reflex was measured concomitantly to monitor changes in alpha-motoneuron excitability. Following approval from the university's ethical committee, 50 healthy human volunteers (25 male and 25 female) participated in the study. The subjects ranged in age from 18 to 30 years (mean 22, SD 3). Subjects were randomly allocated equally to a control group or one of four TENS groups. In the TENS groups, stimulation was applied for a total of 15 min over the sural nerve in the left leg. Ipsilateral RIII and H-reflexes were recorded five times during the 45 min experimental period. In addition, subjects also rated pain associated with the RIII reflex using a computerized visual analogue scale (VAS). Statistical analysis using two-way repeated-measures ANOVA showed no differences between groups for H-reflex, RIII reflex nor VAS data. These results suggest that TENS does not significantly affect either of the two reflexes, at least using the parameters and application time in the current study.
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Affiliation(s)
- D M Walsh
- Rehabilitation Sciences Research Group, School of Health Sciences, University of Ulster at Jordanstown, Co. Antrim BT37 0QB, Northern Ireland
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Cramp FL, Noble G, Lowe AS, Walsh DM, Willer JC. A controlled study on the effects of transcutaneous electrical nerve stimulation and interferential therapy upon the RIII nociceptive and H-reflexes in humans. Arch Phys Med Rehabil 2000; 81:324-33. [PMID: 10724078 DOI: 10.1016/s0003-9993(00)90079-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
OBJECTIVE To study the effect of transcutaneous electrical nerve stimulation (TENS) and interferential therapy (IFT) upon the RIII nociceptive reflex and H-reflex. DESIGN Double-blind conditions. PARTICIPANTS Seventy healthy subjects were randomly allocated to one of seven groups (n = 10 per group): Control, TENS 1 (5 Hz), TENS 2 (100 Hz), TENS 3 (200 Hz), IFT 1 (5 Hz), IFT 2 (100 Hz), IFT 3 (200 Hz). INTERVENTION In the treatment groups, stimulation was applied over the right sural nerve for 15 minutes. MAIN OUTCOME MEASURES Ipsilateral RIII and H-reflexes were recorded before treatment, immediately after treatment, and subsequently at 25, 35, and 45 minutes. Subjects rated the pain associated with the RIII reflex using a computerized visual analogue scale (VAS). RESULTS Statistical analysis using ANOVA showed no significant differences between baseline and posttreatment measurement for RIII reflex, H-reflex, or VAS data. CONCLUSION These results suggest that neither type of electrical stimulation (TENS or IFT) affects the RIII or H-reflexes, at least using the parameters and application time in this study.
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Affiliation(s)
- F L Cramp
- Rehabilitation Sciences Research Group, School of Health Sciences, University of Ulster at Jordanstown, Northern Ireland
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Ellaway PH, Davey NJ, Maskill DW, Rawlinson SR, Lewis HS, Anissimova NP. Variability in the amplitude of skeletal muscle responses to magnetic stimulation of the motor cortex in man. ELECTROENCEPHALOGRAPHY AND CLINICAL NEUROPHYSIOLOGY 1998; 109:104-13. [PMID: 9741800 DOI: 10.1016/s0924-980x(98)00007-1] [Citation(s) in RCA: 125] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We have investigated variability in the amplitude of compound motor evoked potentials (cMEPs) in right and left thenar and wrist extensor muscles in response to synchronous bilateral transcranial magnetic stimulation (TMS) of the motor cortices using two figure-of-eight stimulating coils. Trials of 50 stimuli revealed a wide range of variability in cMEP amplitudes in relaxed muscles (coefficient of variation, range 0.22-1.12). The amplitudes of the cMEPs in one muscle correlated positively with those in the others. The r2 values (mean +/- SEM) were 0.27 +/- 0.06 for muscles on the same side of the body and 0.19 +/- 0.04 for muscles on opposite sides. Employing the ECG to trigger TMS, clamping the coil relative to the head or altering the orientation of the coil all failed to affect the variability of cMEPs. We conclude that fluctuations in excitability of the corticospinal pathway give rise to the variability in the response to TMS, that they are wide-ranging with respect to the muscles affected, and include a bilateral component. We argue that the variability reveals fluctuations in excitability mainly at the cortical rather than the spinal level. We suggest that measures of variability might provide an indication of cortical activity in conditions where consciousness and voluntary movement are compromised.
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Affiliation(s)
- P H Ellaway
- Department of Sensorimotor Systems, Imperial College School of Medicine, Charing Cross Hospital, London, UK.
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