Siobhan C Fitzpatrick1, Billy L Luu2, Jane E Butler3, Janet L Taylor4. 1. Neuroscience Research Australia, Barker Street, Randwick, NSW, Australia; University of New South Wales, Sydney, NSW, Australia. Electronic address: s.fitzpatrick@neura.edu.au. 2. Neuroscience Research Australia, Barker Street, Randwick, NSW, Australia; University of New South Wales, Sydney, NSW, Australia. Electronic address: b.luu@neura.edu.au. 3. Neuroscience Research Australia, Barker Street, Randwick, NSW, Australia; University of New South Wales, Sydney, NSW, Australia. Electronic address: j.butler@neura.edu.au. 4. Neuroscience Research Australia, Barker Street, Randwick, NSW, Australia; University of New South Wales, Sydney, NSW, Australia. Electronic address: j.taylor@neura.edu.au.
Abstract
OBJECTIVE: To examine whether more paired corticospinal-motoneuronal stimulation (PCMS) is more effective at inducing spinal level plasticity. METHODS: To produce facilitation, corticospinal volleys evoked by motor cortical transcranial magnetic stimulation (TMS) were timed to arrive at corticospinal-motoneuronal synapses prior to antidromic potentials evoked in motoneurones by electrical brachial plexus stimulation. Paired stimuli were delivered repeatedly. 50-pair conditioning (50-PCMS) was compared to 100 pairs in single block (100-PCMSsingle) and spaced (2 blocks of 50, 15-min break; 100-PCMSspaced) patterns, and to 50 single, unpaired TMS (50-TMS). Biceps responses to cervicomedullary stimulation (cervicomedullary motor evoked potentials, CMEPs) and TMS (motor evoked potentials, MEPs) were measured before and for 1h after conditioning (recorded each 5 min). RESULTS: After 100-PCMS, average CMEP areas were increased by 46 ± 55% (mean ± SD; n=10; 100-PCMSsingle) and 71 ± 99% (100-PCMSspaced). 50-PCMS produced a non-significant 6 ± 40% increase. After 100-PCMSsingle and 100-PCMSspaced, CMEPs were larger than those after 50-TMS from 0 to 60 min (p<0.05). 100-PCMSsingle and 100-PCMSspaced produced more reliable changes than 50-PCMS. Overall, MEPs were larger at 35-60 min; however there were no differences between conditioning protocols. CONCLUSIONS: More PCMS produces more reliable enhancement of corticospinal transmission. SIGNIFICANCE: This technique has therapeutic potential to improve muscle control in patients with reduced descending drive.
RCT Entities:
OBJECTIVE: To examine whether more paired corticospinal-motoneuronal stimulation (PCMS) is more effective at inducing spinal level plasticity. METHODS: To produce facilitation, corticospinal volleys evoked by motor cortical transcranial magnetic stimulation (TMS) were timed to arrive at corticospinal-motoneuronal synapses prior to antidromic potentials evoked in motoneurones by electrical brachial plexus stimulation. Paired stimuli were delivered repeatedly. 50-pair conditioning (50-PCMS) was compared to 100 pairs in single block (100-PCMSsingle) and spaced (2 blocks of 50, 15-min break; 100-PCMSspaced) patterns, and to 50 single, unpaired TMS (50-TMS). Biceps responses to cervicomedullary stimulation (cervicomedullary motor evoked potentials, CMEPs) and TMS (motor evoked potentials, MEPs) were measured before and for 1h after conditioning (recorded each 5 min). RESULTS: After 100-PCMS, average CMEP areas were increased by 46 ± 55% (mean ± SD; n=10; 100-PCMSsingle) and 71 ± 99% (100-PCMSspaced). 50-PCMS produced a non-significant 6 ± 40% increase. After 100-PCMSsingle and 100-PCMSspaced, CMEPs were larger than those after 50-TMS from 0 to 60 min (p<0.05). 100-PCMSsingle and 100-PCMSspaced produced more reliable changes than 50-PCMS. Overall, MEPs were larger at 35-60 min; however there were no differences between conditioning protocols. CONCLUSIONS: More PCMS produces more reliable enhancement of corticospinal transmission. SIGNIFICANCE: This technique has therapeutic potential to improve muscle control in patients with reduced descending drive.
Authors: Lasse Christiansen; Bing Chen; Yuming Lei; M A Urbin; Michael S A Richardson; Martin Oudega; Milap Sandhu; W Zev Rymer; Randy D Trumbower; Gordon S Mitchell; Monica A Perez Journal: Exp Neurol Date: 2020-09-25 Impact factor: 5.620
Authors: Tomofumi Yamaguchi; Mikkel M Beck; Eva R Therkildsen; Christian Svane; Christian Forman; Jakob Lorentzen; Bernard A Conway; Jesper Lundbye-Jensen; Svend S Geertsen; Jens B Nielsen Journal: Physiol Rep Date: 2020-08