NEURAL CONTROL OF THE SOLEUS H –REFLEX IS RELATED TO THE LATERALITY PATTERN IN LIMBS

Background: Results from performance studies suggested the relationship of lower limb dominance with handedness in right and left – handers, what brings support to some other findings suggesting the role of peripheral factors in the neural control of movements Objective: The aim of the study was toinvestigate the effect of laterality pattern on the neural mechanisms of motor control on peripheral level. Design.The laterality evaluation and the motor evoked potentials of dominant and non dominant limbs were provided, by the use of the H-reflex circuitry. Setting: Experiment was performed in the motor diagnostics laboratory of the Academy of Physical education in Katowice, Poland in June 2009. Participants: 20 young male adults aged 21-23 presenting two laterality patterns in hand-foot combination (right handed-right footed and left handed-left footed groups) took part in the experiment. All of them were carefully screened to eliminate any neurological or muscle diseases or trauma and gave informed consent . Methods: A comparison of the soleus H-reflex parameters elicited at rest in lower extremities. The soleus H-reflex and the direct motor response (M-wave) were elicited in lower extremities of each participant in the same laboratory session. Main outcome measures: Onset latencies as well as min-max amplitudes of the M-wave and the H-reflex were taken into an analysis. Additionally, the motor and sensory conduction velocities were calculated as well as symmetry coefficients of response parameters. Results: The analysis of symmetry coefficients (SC) of direct and late motor responses confirmed differences between two laterality patterns in amplitude and latency of the H-reflex as well as in a sensory conduction velocity (p< 0,05), but not in M-wave parameters. The amplitude of the H-reflex and the calculated sensory Ia afferent conduction velocity in the dominant lower extremity were significantly depressed in the right-sided group in comparison to the left-sided group (p=0.001). The right- sided group presented significantly faster motor fibers conduction velocity in the dominant leg (p=0.006), with no similar effect in the left-sided group. Conclusion: The neural control of the H-reflex elicited at rest is related to the laterality pattern in Hand-foot combination in healthy adults. It strongly suggests the possible existence of intrinsic control mechanisms of the afferent feedback related to functional dominance in human limbs.     

EMG analysis in 78 cases with motor neuron disease

This paper analysed the FMGs of 78 cases with the motor neuron disease(MND). The EMG of all patients showed following characteristics that the average duration of wave prolonged, the average voltage increased and it was found that fibrillation and fasciculatton potentials appeared spontaneously. The fibrillation potential of ENG waa related to course of disease. In the patients whose course of disease was short, the fibri llation potential increased obviously, while in the cases of chronic MND, It usually decreased. The motor nerve conduction velocity of most pa tients (41%) reduced, however, the sensory nerve conduction velocity was normal but two. We reviewed some references about EMG of the motor neuron disease and discussed their characteristics and mechanism     

Anatomical feasibility of vagus nerve esophageal branch transfer to the phrenic nerve

This study measured the vagus and phrenic nerves from 12 adult cadavers. We found that the width and thickness of the vagus and phrenic nerves were different in the chest. The distance from the point of the vagus nerve and phrenic nerve on the plane of the inferior border of portal pulmonary arteries (T point) was approximately 7 cm to the diaphragm and was approximately 10 cm to the clavicle level. The number of motor fibers in the vagus nerves was 1 716 ± 362, and the number of nerve fibers was 4 473 ± 653. The number of motor fibers in the phrenic nerves ranged from 3 078 ± 684 to 4 794 ± 638, and the number of nerve fibers ranged from 3 437 ± 642 to 5 071 ± 723. No significant difference was found in the total number of nerve fibers. The results suggest that width, thickness, and total number of nerve fibers are similar between the vagus and phrenic nerves, but the number of motor fibers is different between them.     

脑皮质电刺激对癫痫大鼠脑皮质兴奋性的影响

目的 观察重复脑皮质电刺激对氯化铁诱发慢性癫痫大鼠模型脑皮质兴奋性的影响.方法 通过在运动感觉区脑皮质注射氯化铁建立慢性癫痫大鼠模型,给予脑皮质低频(1 Hz)低强度(0.1 mA)和低频(1 Hz)高强度(1.0 mA)、高频(100 Hz)低强度(0.1 mA)和高频(100 Hz)高强度(1.0 mA)不同的重复电刺激,检测电刺激前后脑皮质后放电阈值、后放电时程和行为学评分.假刺激慢性癫痫大鼠作为对照组.结果 后放电阈值低频低强度组(2.10±0.38)mA与对照组(1.50±0.33)mA相比差异有统计学意义(P＜0.05).行为学评分和后放电时程各组与对照组相比差异无统计学意义.行为学评分与后放电阈值的比值低频低强度组(1.88±0.60)和低频高强度组(2.18±0.38)与对照组(3.22±0.67)相比差异有统计学意义(P＜0.01和P＜0.05).结论 重复低频低强度脑皮质电刺激可以升高氯化铁诱发慢性癫痫大鼠模型的脑皮质后放电阈值,降低脑皮质兴奋性,提示合适参数的脑皮质电刺激对氯化铁诱发大鼠癜痫具有抑制作用.     

Effect of post-stroke sensory disorders on the recovery processes of motor function and activity of daily living*☆ A non-randomized synchronical controlled trial

BACKGROUND: In the rehabilitation of stroke patients, clinicians usually concentrate on motor problems, such as spasm of limbs and restriction of joint motion, while sensory and perceptive problems are almost always neglected, although they are just as important. One such area is the sensory disorder. OBJECTIVE: To evaluate the motor function and activities of daily living in stroke patients with and without sensory disorders after treatment of integrated western and Chinese medicine. DESIGN: A non-randomized synchronically controlled trial. SETTING: First Affiliated Hospital of Tianjin College of Traditional Chinese Medicine. PARTICIPANTS: Totally 500 stroke inpatients were selected from the Department of Acupuncture and Massage, the First Affiliated Hospital of Tianjin College of Traditional Chinese Medicine from January 2003 to December 2004. They all had suffered from stroke in the last 4 weeks and accompanied by sensory disorder of the ipsilateral limb to different severity. The patients were all accorded with the Diagnostic and Efficacy Evaluative Standards for Stroke (in trial) set by the Encephalopathy Emergency Assistant Group, the State Administration of Traditional Chinese Medicine in 1995, and they were diagnosed by imaging examination. The patients were stratified into sensory disorder group (n =220) and normal sense group (n =280). Informed consent for the detected items and therapeutic program was obtained from the relatives of all the participants. The study was approved by the hospital ethical committee. METHODS: All the patients were treated with acupuncture of Xing Nao Kai Qiao for restoring consciousness and inducing resuscitation, assisted by traditional Chinese medicine and western medicine specific to corresponding symptoms. The therapeutic principles were restoring consciousness and inducing resuscitation, nourishing liver and kidney, and dredging meridian. In addition, the patients were given western medical treatments for decreasing intracranial pressure, thrombolysis, reducing blood viscosity, anticoagulation, anti-arteriosclerosis, ameliorating microcirculation, also administrated with activator for nerve cells. MAIN OUTCOME MEASURES: ① The severity of motor function deficit was evaluated using clinical neurological deficit score for stroke patients set by the Fourth National Academic Meeting for Cerebrovascular Disease in 1995; ② The activities of daily living was evaluated with Barthel Index, the higher the score, the better the independence, and the less the dependence. RESULTS: All the 500 stroke patients were involved in the final analysis of results. ① The neurological deficit scores before treatment had no significant difference between the two groups (P > 0.05), but the scores after treatment were significantly decreased as compared with those before treatment in both groups (t =6.59, 12.43, P < 0.01). The neurological deficit score after treatment in the normal sense group was significantly lower than that in the sensory disorder group (t =1.63, P < 0.05). ② The scores of activities of daily living after treatment were significantly increased as compared with those before treatment in both groups (t =16.03, 25.10, P < 0.01). The scores of activities of daily living in the normal sense group were higher than those in the sensory disorder group both before and after treatment (t =6.07, 14.26, P < 0.05). CONCLUSION: Sensory disorders have obvious negative effects on the recovery of motor function and activities of daily living of stroke patients.     

迷走神经刺激术治疗顽固性癫痫初步探讨

Objective To investigate the effectiveness of vagus nerve stimulation (VNS) therapy in intractable epilepsy. Methods VNS were performed in twenty - one patients. The generator was turned on 2 weeks after operation. Stimulation parameters were adjusted gradually. The output currents adjusted from 0.25 mA, and less than 3.0 mA. Stimulative time was 30 s ON and 5 min OFF, the frequency was from 20to 30 Hz, and the pulse width was from 250 μs to 1000 μs. The patients were followed up so as to analysis the effectiveness. Results After4 - 16 months of intermittent stimulation of the vagus nerve, grade Ⅰ in 3 patients, grade Ⅱ in 7 patients, grade Ⅲ in 9 patients and grade Ⅴ in 2 patients. Among them, seizure frequency was reduced over 50% occurred in 10 patients. Conclusion VNS can reduce seizure frequency,improve the quality of life in patients with intractable epilepsy, and it is a minimal invasive surgery with few side effects.     

迷走神经刺激术治疗顽固性癫痫初步探讨

Objective To investigate the effectiveness of vagus nerve stimulation (VNS) therapy in intractable epilepsy. Methods VNS were performed in twenty - one patients. The generator was turned on 2 weeks after operation. Stimulation parameters were adjusted gradually. The output currents adjusted from 0.25 mA, and less than 3.0 mA. Stimulative time was 30 s ON and 5 min OFF, the frequency was from 20to 30 Hz, and the pulse width was from 250 μs to 1000 μs. The patients were followed up so as to analysis the effectiveness. Results After4 - 16 months of intermittent stimulation of the vagus nerve, grade Ⅰ in 3 patients, grade Ⅱ in 7 patients, grade Ⅲ in 9 patients and grade Ⅴ in 2 patients. Among them, seizure frequency was reduced over 50% occurred in 10 patients. Conclusion VNS can reduce seizure frequency,improve the quality of life in patients with intractable epilepsy, and it is a minimal invasive surgery with few side effects.     

End-to-side neurorrhaphy repairs peripheral nerve injury: sensory nerve induces motor nerve regeneration

End-to-side neurorrhaphy is an option in the treatment of the long segment defects of a nerve.It involves suturing the distal stump of the disconnected nerve(recipient nerve) to the side of the intimate adjacent nerve(donor nerve).However,the motor-sensory specificity after end-to-side neurorrhaphy remains unclear.This study sought to evaluate whether cutaneous sensory nerve regeneration induces motor nerves after end-to-side neurorrhaphy.Thirty rats were randomized into three groups:(1) end-to-side neurorrhaphy using the ulnar nerve(mixed sensory and motor) as the donor nerve and the cutaneous antebrachii medialis nerve as the recipient nerve;(2) the sham group:ulnar nerve and cutaneous antebrachii medialis nerve were just exposed;and(3) the transected nerve group:cutaneous antebrachii medialis nerve was transected and the stumps were turned over and tied.At 5 months,acetylcholinesterase staining results showed that 34% ± 16% of the myelinated axons were stained in the end-to-side group,and none of the myelinated axons were stained in either the sham or transected nerve groups.Retrograde fluorescent tracing of spinal motor neurons and dorsal root ganglion showed the proportion of motor neurons from the cutaneous antebrachii medialis nerve of the end-to-side group was 21% ± 5%.In contrast,no motor neurons from the cutaneous antebrachii medialis nerve of the sham group and transected nerve group were found in the spinal cord segment.These results confirmed that motor neuron regeneration occurred after cutaneous nerve end-to-side neurorrhaphy.     

Auditory steady-state evoked response in diagnosing and evaluating hearing in infants

Auditory steady-state evoked response (ASSR) is one of the new objective electrophysiological methods to test hearing in infants. It can provide a reliable and complete audiogram with specific frequency to help the hearing diagnosis and rehabilitation of hearing and languaging following auditory screening.OBJECTIVE: To compare the response threshold of ASSR with auditory threshold of visual reinforcement audiometry (VRA) in infants failed in the hearing screening for investigating their hearing loss.DESIGN: A comparative observation.SETTINGS: Maternal and child health care hospitals of Guangdong province, Shunde city, Nanhai city and Huadu district.PARTICIPANTS: Totally 321 infants of 0-3 years undergoing ASSR test were selected from the Hearing Center of Guangdong Maternal and Child Health Care Hospital from January 2002 to December 2004.Informed consents were obtained from their guardians. There were 193 cases (60.2%) of 0-6 months, 31 cases (9.7%) of 7-12 months, 17 cases (5.3%) of 13-18 months, 14 cases (4.4%) of 19-24 months, 33 cases of 25-30 months, and 33 cases (10.2%) of 31-36 months.METHODS: ① The 321 infants failed in the hearing screening were tested under sleeping status, the ranges of response threshold distribution in ASSR of different frequencies were analyzed in each age group. ② The infants above 2 years old were also tested with VRA, and their response thresholds were compared between VRA and ASSR. ③ Evaluative standards: The response threshold was ＜ 30 dB for normal hearing, 31-50 dB for mild hearing loss, 51-70 dB for moderate hearing loss, 71-90 dB for severe hearing loss, and ＞ 91 dB for extremely severe hearing loss.MAIN OUTCOME MEASURES: ① ASSR results of the infants failed in the screening; ② Proportion of cases of each response threshold in each age group; ③ Comparison of ASSR response thresholds and VRA auditory thresholds in the infants of 2-3 years old.RESULTS: ①The response threshold was ＜ 30 dB in 47.4% of the 321 infants failed in the initial hearing screening and secondary screening after 42 days. ② Severe to extremely severe hearing loss was detected in only 16 cases (8.3%) of the 193 infants of 0-6 months, in 9 cases (27.3%) of the 33 infants of 25-30 months,and 13 cases (39.4%) of the 33 infants of 31-36 months. Of the 193 infants of 0-6 months old who failed in the initial screening and the second screening after 42 days, the ASSR auditory threshold was ＜ 30 dB in 97 cases (50.26%), 31-50 dB in 63 cases (32.6%), 51-70 dB in 17 cases (8.8%), 71-90 dB in 7 cases (3.6%), and ＞ 91 dB in 9 cases (4.7%). ③ Among the 321 infants failed in the screening, the auditory threshold in the 6 age groups was ＜ 30 dB in 47.4%, 31-50 dB in 27.1%, 51-70 dB in 8.4%, 71-90 dB in 6.2%, and ＞ 91 dB in 10.9%. ④The difference between ASSR response threshold and VRA auditory thresholds was 6-18 dB in the normal hearing group, mild and moderate hearing loss groups, and there was high correlation between them. The difference of ASSR and VRA thresholds was less than 5 dB between extremely severe and severe hearing loss groups, 5-13 dB between extremely severe and moderate-to-severe hearing loss groups (P ＜ 0.05), and there was no significant differences between severe and moderate-to-severe hearing loss groups (P ＞ 0.05).CONCLUSION: ① The hearing was normal in about half of the infants, although they failed in the primary screening and secondary screening. ② The proportion of the severity of hearing loss was increased along with aging. ③ Mild and moderate hearing losses are dominant in infants. ④ ASSR is reliable to evaluate the hearing of infants.     

The threshold of cortical electrical stimulation for mapping sensory and motor functional areas

This study aimed to investigate the threshold of cortical electrical stimulation (CES) for functional brain mapping during surgery for the treatment of rolandic epilepsy. A total of 21 patients with rolandic epilepsy who underwent surgical treatment at the Beijing Institute of Functional Neurosurgery between October 2006 and March 2008 were included in this study. Their clinical data were retrospectively collected and analyzed. The thresholds of CES for motor response, sensory response, and after discharge production along with other threshold-related factors were investigated. The thresholds (mean ± standard deviation) for motor response, sensory response, and after discharge production were 3.48 ± 0.87, 3.86 ± 1.31, and 4.84 ± 1.38 mA, respectively. The threshold for after discharge production was significantly higher than those of both the motor and sensory response (both p < 0.05). A negative linear correlation was found between the threshold of after discharge production and disease duration. Using the CES parameters at a stimulation frequency of 50 Hz and a pulse width of 0.2 ms, the threshold of sensory and motor responses were similar, and the threshold of after discharge production was higher than that of sensory and motor response.     

Language and motor function thresholds during pediatric extra-operative electrical cortical stimulation brain mapping

Objective

To examine current thresholds and their determinants for language and motor mapping with extra-operative electrical cortical stimulation (ECS).

Extraoperative cortical stimulation of motor function in children

The purpose of the study was to investigate factors altering the amperage threshold needed to provoke functional responses in children with epilepsy. Twenty patients (4–18 years of age) who underwent epilepsy surgery at our institution from 1996–2000 after insertion of subdural grid electrodes were reviewed retrospectively. Extraoperative electrical cortical stimulation was performed with 50-Hz biphasic pulses of 0.2 ms in duration using a “distance reference” technique. Amperage thresholds of primary motor responses and afterdischarges were evaluated. The patients were grouped according to underlying pathology: eight with neuronal migration disorders (group A) and 12 with other disorders (group B). The motor cortex was defined successfully in all children because the afterdischarges threshold was higher than the motor cortical threshold. Amperage thresholds ranged from 2–20 mA (mean = 7.7) for primary motor function. An inverse relationship was found between amperage threshold and age: the younger the patient, the higher the threshold (P = 0.0005). Patients in group A required a higher amperage (2–20 mA, MEAN = 8.6) for motor cortical mapping than those in group B (2–14 mA, MEAN = 6.4). Younger children with neuronal migration disorders require a higher amperage threshold to achieve adequate motor functional mapping with careful observation of afterdischarges.     

Anatomical and functional distribution of functional MRI language mapping

ObjectiveThe aim of the present study was to compare localization of the language cortex using electrical cortical stimulation (ECS) and functional magnetic resonance imaging (fMRI) to establish the relevance of fMRI language mapping.MethodsLanguage mapping with fMRI and functional ECS mapping were retrospectively compared in ten patients with refractory epilepsy who underwent fMRI language mapping and functional ECS mapping between June 2012 and April 2019. A shiritori task, a popular Japanese word chain game, was used for fMRI language mapping.ResultsBOLD signal activation was observed in the left inferior frontal gyrus (including the pars opecularis and the pars triangularis), and superior temporal gyrus, which is a language-related area, as well as in the left superior and middle frontal gyri, the intraparietal sulcus, and fusiform gyrus. These results were compared with ECS to elucidate the functional role of the activated areas during fMRI language tasks. These activated areas included language areas, negative motor areas, supplementary motor areas (SMAs), and non-functional areas.ConclusionThe activated areas of fMRI language mapping include language-related areas, the negative motor area, and SMAs. These findings suggest the involvement of language and higher order motor networks in verbal expression.     

Real‐time presurgical resting‐state fMRI in patients with brain tumors: Quality control and comparison with task‐fMRI and intraoperative mapping

Resting‐state functional magnetic resonance imaging (rsfMRI) is a promising task‐free functional imaging approach, which may complement or replace task‐based fMRI (tfMRI) in patients who have difficulties performing required tasks. However, rsfMRI is highly sensitive to head movement and physiological noise, and validation relative to tfMRI and intraoperative electrocortical mapping is still necessary. In this study, we investigate (a) the feasibility of real‐time rsfMRI for presurgical mapping of eloquent networks with monitoring of data quality in patients with brain tumors and (b) rsfMRI localization of eloquent cortex compared with tfMRI and intraoperative electrocortical stimulation (ECS) in retrospective analysis. Five brain tumor patients were studied with rsfMRI and tfMRI on a clinical 3T scanner using MultiBand(8)‐echo planar imaging (EPI) with repetition time: 400 ms. Moving‐averaged sliding‐window correlation analysis with regression of motion parameters and signals from white matter and cerebrospinal fluid was used to map sensorimotor and language resting‐state networks. Data quality monitoring enabled rapid optimization of scan protocols, early identification of task noncompliance, and head movement‐related false‐positive connectivity to determine scan continuation or repetition. Sensorimotor and language resting‐state networks were identifiable within 1 min of scan time. The Euclidean distance between ECS and rsfMRI connectivity and task‐activation in motor cortex, Broca's, and Wernicke's areas was 5–10 mm, with the exception of discordant rsfMRI and ECS localization of Wernicke's area in one patient due to possible cortical reorganization and/or altered neurovascular coupling. This study demonstrates the potential of real‐time high‐speed rsfMRI for presurgical mapping of eloquent cortex with real‐time data quality control, and clinically acceptable concordance of rsfMRI with tfMRI and ECS localization.     

The effectiveness of low-frequency stimulation for mapping cortical function

OBJECTIVE: To establish the efficacy and safety of low-frequency electrical stimulation for cortical brain mapping. METHODS: Cortical function was mapped using electrical stimulation in epilepsy patients with chronically implanted intracranial subdural electrodes. Contacts overlying motor, sensory, visual, and language cortex were stimulated at frequencies of 5, 10, and 50 Hz, using current levels ranging from 1 to 17.5 mA for 3-5 s. The current intensity and incidence at which functional alterations and afterdischarges (ADs) occurred were recorded. The modified McNemar test for nonindependent measures was used to analyze the data. RESULTS: 122 electrode contact pairs were electrically stimulated at least two different frequencies in 14 patients. Functional alterations were obtained at all stimulation frequencies (5, 10, and 50 Hz) at generally similar rates. The likelihood of producing an AD correlated with stimulation frequency, and lower-frequency stimulation was less likely to provoke an AD. Higher current intensity was required to induce both functional responses and ADs at low-frequency stimulation than high-frequency stimulation. While overall rates of producing functional changes were similar, differences in functional response with regard to frequency were noted at individual cortical sites. CONCLUSION: 5- and 10-Hz stimulation are as effective for mapping cortical function as 50-Hz stimulation and produce fewer ADs. We recommend that mapping of cortical function be started with 5-Hz-frequency stimulation. Higher frequencies should be used in suspect cortex if no symptoms or signs are produced with 5-Hz stimulation.     

Vitamin B12 supplementation improves heart rate variability in healthy elderly Indian subjects

The vestibular system plays an important role in control of arterial pressure (AP) upon head-up tilt (HUT). To examine this role in human subjects, we previously compared changes in AP with and without high-amplitude galvanic vestibular stimulation (GVS), which is considered to obscure vestibular input. In contrast, regarding sensory function in skin and muscle, it has been documented that low-amplitude electrical stimulation improves both sensitivity and response. In the present study, we examined whether GVS of smaller amplitude improves AP control upon HUT. GVS was applied at the amplitude of the somatosensory threshold (0.3-0.8 mA), 0.1 mA over the threshold, and 0.1 and 0.2 mA below the threshold during HUT. AP decreased at the onset of HUT compared with that in the supine position in 15 of 25 subjects without GVS (-12±2 mmHg), but applying GVS at 0.1 mA below the somatosensory threshold diminished the decrease (0.3±0.7 mmHg). The APs of another 10 subjects were maintained or decreased by less than 5 mmHg without GVS at the onset of HUT (4±2 mmHg), but applying GVS at the amplitude of 0.1 mA below the somatosensory threshold further increased the AP (12±2 mmHg). GVS at the other amplitudes did not result in AP changes in either group. Thus, subsensory weak GVS enhances AP control at the onset of HUT.     

Reversible motor paralysis in rats after repeated electroconvulsive shock

Repeated electroconvulsive shocks (ECS) delivered at brief (10 to 15 min) intervals through earclip electrodes, induced a reversible motor paralysis in 35% of treated rats. Paralysis was characterized by loss of locomotor activity without apparent loss of sensory functions. It occurred after 10 to 13 shocks regardless of whether stimulation was of subthreshold (40 to 60 mA) or suprathreshold (65 mA) intensity. This phenomenon may provide a useful animal model for the investigation of reversible injury to the spinal cord.     

Cerebral Edema and Vascular Permeability to Serum Proteins Following Electroconvulsive Shock in Rats

The regional brain specific gravity and the cerebrovascular permeability to serum proteins were investigated in rats subjected to electroconvulsive shock (ECS) with different stimulus intensity and different stimulus periods. The following experimental situations were studied: one ECS daily for 9 days (50 mA in 0.3 s), one ECS daily for 9 days (50 mA in 0.9 s), and one ECS three times weekly for 4 weeks (50 mA in 0.3 s). Age-matched animals receiving sham ECS served as controls. In the group having stronger stimulus intensity and in the one treated for 4 weeks, there was an increase in tissue water content in the hypothalamus and in both hypothalamus and hippocampus, respectively. In none of the experimental groups could cerebral edema be demonstrated in parietal cortex or in white matter. The findings point to an increased blood-to-brain transfer of water with increasing stimulus intensity and with the length of the ECS series. The study showed no increased cerebrovascular permeability to serum proteins and no signs of neuronal damage in any of the experimental groups.