Traumatic brain injury, cardiac arrest, intracerebral hemorrhage, and ischemic stroke may cause d... more Traumatic brain injury, cardiac arrest, intracerebral hemorrhage, and ischemic stroke may cause disorders of consciousness (DoC). Repetitive transcranial magnetic stimulation (rTMS) has been used to promote the recovery of disorders of consciousness (DoC) patients. In this meta-analysis, we examined whether rTMS can relieve DoC patient symptoms. We searched through journal articles indexed in PubMed, the Web of Science, Embase, Scopus, and the Cochrane Library until 20 April 2023. We assessed whether studies used rTMS as an intervention and reported the pre- and post-rTMS coma recovery scale-revised (CRS-R) scores. A total of 207 patients from seven trials were included. rTMS significantly improved the recovery degree of patients; the weighted mean difference (WMD) of the change in the CRS-R score was 1.89 (95% confidence interval (CI): 1.39–2.39; p < 0.00001) in comparison with controls. The subgroup analysis showed a significant improvement in CRS-R scores in rTMS over the dors...
Background: Brain stimulation motor-evoked potentials (MEPs) are transient signals and not period... more Background: Brain stimulation motor-evoked potentials (MEPs) are transient signals and not periodic signals, and thus, they differ significantly in their properties from classical surface electromyograms. Unsuitable pre-processing of MEPs due to inappropriate filter settings leads to distortions. Filtering of extensor carpi radialis MEPs with transient signal characteristics of 20 subjects was examined. The effects of a 1st-order Butterworth high-pass filter (HPF) with different cut-off frequencies 1 Hz, 20 Hz, 40 Hz, and 80 Hz and a 5 Hz Butterworth high-pass filter with degrees 1st, 2nd, 4th, 8th-order are investigated for the filter output. Results: The filtering of the MEPs with an inappropriate filter setting led to distortions on the parameters peak-to-peak amplitudes of the MEP (MEPpp) and the absolute integral of the MEP (MEParea). The lowest distortions of all of the examined filter parameters were revealed after filtering with the lowest filter order and the lowest cut-off...
Optimal motor control requires the effective integration of multi-modal information. Visual infor... more Optimal motor control requires the effective integration of multi-modal information. Visual information of movement performed by others even enhances potentials in the upper motor neurons, through the mirror-neuron system. On the other hand, it is known that motor control is intimately associated with afferent proprioceptive information. Kinaesthetic information is also generated by passive, external-driven movements. In the context of sensory integration, its an important question, how such passive kinaesthetic information and visually perceived movements are integrated. We studied the effects of visual and kinaesthetic information in combination, as well as isolated, on sensorimotor-integration – compared to a control condition. For this, we measured the change in the excitability of motor cortex (M1) using low-intensity TMS. We hypothesised that both visual motoneurons and kinaesthetic motoneurons could enhance the excitability of motor responses. We found that passive wrist move...
Journal of Sports Science and Medicine, Mar 1, 2011
The electric field induced by repetitive peripheral magnetic stimulation (RPMS) is able to activa... more The electric field induced by repetitive peripheral magnetic stimulation (RPMS) is able to activate muscles artificially due to the stimulation of deep intramuscular motor axons. RPMS applied to the muscle induces proprioceptive input to the central nervous system in different ways. Firstly, the indirect activation of mechanoreceptors and secondly, direct activation of afferent nerve fibers. The purpose of the study was to examine the effects of RPMS applied to the soleus. Thirteen male subjects received RPMS once and were investigated before and after the treatment regarding the parameters maximal M wave (Mmax), maximal H-reflex (Hmax), Hmax/Mmax-ratio, Hmax and Mmax onset latencies and plantar flexor peak twitch torque associated with Hmax (PTH). Eleven male subjects served as controls. No significant changes were observed for Hmax and PTH of the treatment group but the Hmax/Mmax-ratio increased significantly (p = 0.015) on account of a significantly decreased Mmax (p = 0.027). Hm...
Electromyography and clinical neurophysiology, 1989
Even under field conditions the registration of EMG-signals is often interfered with artifacts. F... more Even under field conditions the registration of EMG-signals is often interfered with artifacts. For quantitative signal processing it is necessary to eliminate artifacts and noise from the EMG raw data. We show a simple and efficient way with the help of a recursive digital first order Butterworth filter. This filter-type has a great slope steepness and requires minimal calculations. The algorithm is derived and easily programmable.
Introduction: The electric field induced by magnetic stimulation (MS) is able to stimulate intram... more Introduction: The electric field induced by magnetic stimulation (MS) is able to stimulate intramuscular motor axons, which evoke muscle contraction (Machetanz, 1994). The purpose of the present study was to examine the effects of repetitive MS (rMS) of the m. soleus (So) on the Hmax/Mmax-ratio. Methods: 24 healthy male students took part in a double blind study. Subjects were randomly assigned to a treatment group (G1: n = 13; age 24.08 ± 1.98; weight 77.77 ± 7.34; height 181.31 ± 6.76) and a control group (G2: n = 11; 23.00 ± 1.55; 79.55 ± 11.67; 182.00 ± 8.31). rMS was delivered using a MagProR30 stimulator and a MC-125 circular coil. The stimulation protocol included the application of symmetric biphasic pulses, a frequency of 15 Hz, 20 trains, inter train interval 2sec, 100 bursts per train and 40% stimulator output. rMS took place once and was applied to So of G1. G2 received a placebo rMS. Before and after rMS Hmax/Mmax-ratios and torque (T in Nm), produced by plantar flexion...
Das Forschungsprojekt „Eintauchtechnik“ an der Universitat Rostock beschaftigt sich mit dem Probl... more Das Forschungsprojekt „Eintauchtechnik“ an der Universitat Rostock beschaftigt sich mit dem Problem der Spritzerbildung beim Wasserspringen aus einer interdisziplinaren Perspektive. Ein stromungsdynamisch orientiertes Teilprojekt untersucht am Institut fur Stromungstechnik (Leder und Mitarbeiter) Druckund Geschwindigkeitsverhaltnisse am Modell eines untergetauchten Wasserspringers, um insbesondere der Frage der Spritzerbildung durch Kavitationsphanomene („Spontane“ Blasenbildung durch Unterschreiten des Dampfdruckes) nachzugehen. Hier kann am Modell der Einfluss von Eintauchgeschwindigkeit und Eintauchtechnik (z.B. Durchtauchen oder Abrollen) auf die Form der Spritzerbildung studiert werden.
Even under field conditions the registration of EMG-signals is often interfered with artifacts. F... more Even under field conditions the registration of EMG-signals is often interfered with artifacts. For quantitative signal processing it is necessary to eliminate artifacts and noise from the EMG raw data. We show a simple and efficient way with the help of a recursive digital first order Butterworth filter. This filter-type has a great slope steepness and requires minimal calculations. The algorithm is derived and easily programmable.
The electric field induced by repetitive peripheral magnetic stimulation (RPMS) is able to activa... more The electric field induced by repetitive peripheral magnetic stimulation (RPMS) is able to activate muscles artificially due to the stimulation of deep intramuscular motor axons. RPMS applied to the muscle induces proprioceptive input to the central nervous system in different ways. Firstly, the indirect activation of mechanoreceptors and secondly, direct activation of afferent nerve fibers. The purpose of the study was to examine the effects of RPMS applied to the soleus. Thirteen male subjects received RPMS once and were investigated before and after the treatment regarding the parameters maximal M wave (Mmax), maximal H-reflex (Hmax), Hmax/Mmax-ratio, Hmax and Mmax onset latencies and plantar flexor peak twitch torque associated with Hmax (PTH). Eleven male subjects served as controls. No significant changes were observed for Hmax and PTH of the treatment group but the Hmax/Mmax-ratio increased significantly (p = 0.015) on account of a significantly decreased Mmax (p = 0.027). Hm...
The present study was designed to provide further insight into the mechanistic basis for the impr... more The present study was designed to provide further insight into the mechanistic basis for the improved exercise tolerance following ischemic preconditioning (IPC) by investigating key-determinants of performance and perceived fatigability. Using a randomized, counterbalanced, single-blind, sham-controlled, crossover design, 16 males performed an isometric time-to-exhaustion test with the knee extensors at 20% maximal voluntary torque (MVT) after an IPC and a sham treatment (SHAM). Those who improved their time-to-exhaustion following IPC performed a time-matched IPC trial corresponding to the exercise duration of SHAM (IPCtm). Neuromuscular function was assessed before and after exercise termination during each condition (IPC, IPCtm, and SHAM) to analyze the impact of IPC on performance fatigability and its central and peripheral determinants. Muscle oxygenation (SmO2), muscle activity, and perceptual responses (effort and muscle pain) were recorded during exercise. Performance fatigability as well as its central and peripheral determinants were quantified as percentage pre-post changes in MVT (ΔMVT) as well as voluntary activation (ΔVA) and quadriceps twitch torque evoked by paired electrical stimuli at 100 and 10 Hz (ΔPS100 and ΔPS10⋅PS100–1 ratio), respectively. Time-to-exhaustion, performance fatigability, its determinants, muscle activity, SmO2, and perceptual responses during exercise were not different between IPC and SHAM. However, six participants improved their performance by >10% following IPC (299 ± 71 s) compared to SHAM (253 ± 66 s, d = 3.23). The time-matched comparisons (IPCtm vs. SHAM) indicated that performance fatigability, its determinants, and SmO2 were not affected, while effort perception seemed to be lower (ηp2 = 0.495) in those who improved their time-to-exhaustion. The longer time-to-exhaustion following IPC seemed to be associated with a lower effort perception (ηp2 = 0.380) and larger impairments in neuromuscular function, i.e., larger ΔMVT, ΔVA, and ΔPS10⋅PS100–1 ratio (d = 0.71, 1.0, 0.92, respectively). IPC did neither affect exercise tolerance, performance fatigability, as well as its central and peripheral determinants, nor muscle activity, SmO2, and perceptual responses during submaximal isometric exercise. However, IPC seemed to have an ergogenic effect in a few subjects, which might have resulted from a lower effort perception during exercise. These findings support the assumption that there are ‘responders’ and ‘non-responders’ to IPC.
Traumatic brain injury, cardiac arrest, intracerebral hemorrhage, and ischemic stroke may cause d... more Traumatic brain injury, cardiac arrest, intracerebral hemorrhage, and ischemic stroke may cause disorders of consciousness (DoC). Repetitive transcranial magnetic stimulation (rTMS) has been used to promote the recovery of disorders of consciousness (DoC) patients. In this meta-analysis, we examined whether rTMS can relieve DoC patient symptoms. We searched through journal articles indexed in PubMed, the Web of Science, Embase, Scopus, and the Cochrane Library until 20 April 2023. We assessed whether studies used rTMS as an intervention and reported the pre- and post-rTMS coma recovery scale-revised (CRS-R) scores. A total of 207 patients from seven trials were included. rTMS significantly improved the recovery degree of patients; the weighted mean difference (WMD) of the change in the CRS-R score was 1.89 (95% confidence interval (CI): 1.39–2.39; p < 0.00001) in comparison with controls. The subgroup analysis showed a significant improvement in CRS-R scores in rTMS over the dors...
Background: Brain stimulation motor-evoked potentials (MEPs) are transient signals and not period... more Background: Brain stimulation motor-evoked potentials (MEPs) are transient signals and not periodic signals, and thus, they differ significantly in their properties from classical surface electromyograms. Unsuitable pre-processing of MEPs due to inappropriate filter settings leads to distortions. Filtering of extensor carpi radialis MEPs with transient signal characteristics of 20 subjects was examined. The effects of a 1st-order Butterworth high-pass filter (HPF) with different cut-off frequencies 1 Hz, 20 Hz, 40 Hz, and 80 Hz and a 5 Hz Butterworth high-pass filter with degrees 1st, 2nd, 4th, 8th-order are investigated for the filter output. Results: The filtering of the MEPs with an inappropriate filter setting led to distortions on the parameters peak-to-peak amplitudes of the MEP (MEPpp) and the absolute integral of the MEP (MEParea). The lowest distortions of all of the examined filter parameters were revealed after filtering with the lowest filter order and the lowest cut-off...
Optimal motor control requires the effective integration of multi-modal information. Visual infor... more Optimal motor control requires the effective integration of multi-modal information. Visual information of movement performed by others even enhances potentials in the upper motor neurons, through the mirror-neuron system. On the other hand, it is known that motor control is intimately associated with afferent proprioceptive information. Kinaesthetic information is also generated by passive, external-driven movements. In the context of sensory integration, its an important question, how such passive kinaesthetic information and visually perceived movements are integrated. We studied the effects of visual and kinaesthetic information in combination, as well as isolated, on sensorimotor-integration – compared to a control condition. For this, we measured the change in the excitability of motor cortex (M1) using low-intensity TMS. We hypothesised that both visual motoneurons and kinaesthetic motoneurons could enhance the excitability of motor responses. We found that passive wrist move...
Journal of Sports Science and Medicine, Mar 1, 2011
The electric field induced by repetitive peripheral magnetic stimulation (RPMS) is able to activa... more The electric field induced by repetitive peripheral magnetic stimulation (RPMS) is able to activate muscles artificially due to the stimulation of deep intramuscular motor axons. RPMS applied to the muscle induces proprioceptive input to the central nervous system in different ways. Firstly, the indirect activation of mechanoreceptors and secondly, direct activation of afferent nerve fibers. The purpose of the study was to examine the effects of RPMS applied to the soleus. Thirteen male subjects received RPMS once and were investigated before and after the treatment regarding the parameters maximal M wave (Mmax), maximal H-reflex (Hmax), Hmax/Mmax-ratio, Hmax and Mmax onset latencies and plantar flexor peak twitch torque associated with Hmax (PTH). Eleven male subjects served as controls. No significant changes were observed for Hmax and PTH of the treatment group but the Hmax/Mmax-ratio increased significantly (p = 0.015) on account of a significantly decreased Mmax (p = 0.027). Hm...
Electromyography and clinical neurophysiology, 1989
Even under field conditions the registration of EMG-signals is often interfered with artifacts. F... more Even under field conditions the registration of EMG-signals is often interfered with artifacts. For quantitative signal processing it is necessary to eliminate artifacts and noise from the EMG raw data. We show a simple and efficient way with the help of a recursive digital first order Butterworth filter. This filter-type has a great slope steepness and requires minimal calculations. The algorithm is derived and easily programmable.
Introduction: The electric field induced by magnetic stimulation (MS) is able to stimulate intram... more Introduction: The electric field induced by magnetic stimulation (MS) is able to stimulate intramuscular motor axons, which evoke muscle contraction (Machetanz, 1994). The purpose of the present study was to examine the effects of repetitive MS (rMS) of the m. soleus (So) on the Hmax/Mmax-ratio. Methods: 24 healthy male students took part in a double blind study. Subjects were randomly assigned to a treatment group (G1: n = 13; age 24.08 ± 1.98; weight 77.77 ± 7.34; height 181.31 ± 6.76) and a control group (G2: n = 11; 23.00 ± 1.55; 79.55 ± 11.67; 182.00 ± 8.31). rMS was delivered using a MagProR30 stimulator and a MC-125 circular coil. The stimulation protocol included the application of symmetric biphasic pulses, a frequency of 15 Hz, 20 trains, inter train interval 2sec, 100 bursts per train and 40% stimulator output. rMS took place once and was applied to So of G1. G2 received a placebo rMS. Before and after rMS Hmax/Mmax-ratios and torque (T in Nm), produced by plantar flexion...
Das Forschungsprojekt „Eintauchtechnik“ an der Universitat Rostock beschaftigt sich mit dem Probl... more Das Forschungsprojekt „Eintauchtechnik“ an der Universitat Rostock beschaftigt sich mit dem Problem der Spritzerbildung beim Wasserspringen aus einer interdisziplinaren Perspektive. Ein stromungsdynamisch orientiertes Teilprojekt untersucht am Institut fur Stromungstechnik (Leder und Mitarbeiter) Druckund Geschwindigkeitsverhaltnisse am Modell eines untergetauchten Wasserspringers, um insbesondere der Frage der Spritzerbildung durch Kavitationsphanomene („Spontane“ Blasenbildung durch Unterschreiten des Dampfdruckes) nachzugehen. Hier kann am Modell der Einfluss von Eintauchgeschwindigkeit und Eintauchtechnik (z.B. Durchtauchen oder Abrollen) auf die Form der Spritzerbildung studiert werden.
Even under field conditions the registration of EMG-signals is often interfered with artifacts. F... more Even under field conditions the registration of EMG-signals is often interfered with artifacts. For quantitative signal processing it is necessary to eliminate artifacts and noise from the EMG raw data. We show a simple and efficient way with the help of a recursive digital first order Butterworth filter. This filter-type has a great slope steepness and requires minimal calculations. The algorithm is derived and easily programmable.
The electric field induced by repetitive peripheral magnetic stimulation (RPMS) is able to activa... more The electric field induced by repetitive peripheral magnetic stimulation (RPMS) is able to activate muscles artificially due to the stimulation of deep intramuscular motor axons. RPMS applied to the muscle induces proprioceptive input to the central nervous system in different ways. Firstly, the indirect activation of mechanoreceptors and secondly, direct activation of afferent nerve fibers. The purpose of the study was to examine the effects of RPMS applied to the soleus. Thirteen male subjects received RPMS once and were investigated before and after the treatment regarding the parameters maximal M wave (Mmax), maximal H-reflex (Hmax), Hmax/Mmax-ratio, Hmax and Mmax onset latencies and plantar flexor peak twitch torque associated with Hmax (PTH). Eleven male subjects served as controls. No significant changes were observed for Hmax and PTH of the treatment group but the Hmax/Mmax-ratio increased significantly (p = 0.015) on account of a significantly decreased Mmax (p = 0.027). Hm...
The present study was designed to provide further insight into the mechanistic basis for the impr... more The present study was designed to provide further insight into the mechanistic basis for the improved exercise tolerance following ischemic preconditioning (IPC) by investigating key-determinants of performance and perceived fatigability. Using a randomized, counterbalanced, single-blind, sham-controlled, crossover design, 16 males performed an isometric time-to-exhaustion test with the knee extensors at 20% maximal voluntary torque (MVT) after an IPC and a sham treatment (SHAM). Those who improved their time-to-exhaustion following IPC performed a time-matched IPC trial corresponding to the exercise duration of SHAM (IPCtm). Neuromuscular function was assessed before and after exercise termination during each condition (IPC, IPCtm, and SHAM) to analyze the impact of IPC on performance fatigability and its central and peripheral determinants. Muscle oxygenation (SmO2), muscle activity, and perceptual responses (effort and muscle pain) were recorded during exercise. Performance fatigability as well as its central and peripheral determinants were quantified as percentage pre-post changes in MVT (ΔMVT) as well as voluntary activation (ΔVA) and quadriceps twitch torque evoked by paired electrical stimuli at 100 and 10 Hz (ΔPS100 and ΔPS10⋅PS100–1 ratio), respectively. Time-to-exhaustion, performance fatigability, its determinants, muscle activity, SmO2, and perceptual responses during exercise were not different between IPC and SHAM. However, six participants improved their performance by >10% following IPC (299 ± 71 s) compared to SHAM (253 ± 66 s, d = 3.23). The time-matched comparisons (IPCtm vs. SHAM) indicated that performance fatigability, its determinants, and SmO2 were not affected, while effort perception seemed to be lower (ηp2 = 0.495) in those who improved their time-to-exhaustion. The longer time-to-exhaustion following IPC seemed to be associated with a lower effort perception (ηp2 = 0.380) and larger impairments in neuromuscular function, i.e., larger ΔMVT, ΔVA, and ΔPS10⋅PS100–1 ratio (d = 0.71, 1.0, 0.92, respectively). IPC did neither affect exercise tolerance, performance fatigability, as well as its central and peripheral determinants, nor muscle activity, SmO2, and perceptual responses during submaximal isometric exercise. However, IPC seemed to have an ergogenic effect in a few subjects, which might have resulted from a lower effort perception during exercise. These findings support the assumption that there are ‘responders’ and ‘non-responders’ to IPC.
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