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991.
目的分析探讨脑干听觉诱发电位(BAEP)及体感诱发电位(SEP)与重型颅脑损伤病人预后的关系。方法应用诱发电位仪对85例重型颅脑损伤患者早期行BAEP及SEP检查,并进行动态监测。结果重复检查BAEP及SEP均正常者,预后良好;BAEP及SEP均异常者,预后极差,与其他几组比较均有显著性差异(P<0.05)。结论BAEP与SEP联合应用并重复检查,可以比较准确的评估重型颅脑损伤患者的预后。 相似文献
992.
《中国神经再生研究》2016,(8):1274-1277
There have been no studies reported on the difference in cortical activation during use of volar and dorsal hand splints. We attempted to investigate the difference in cortical activation in the somatosensory cortical area during use of volar and dorsal hand splints by functional magnetic resonance imaging (fMRI). We recruited eight healthy volunteers. fMRI was performed while subjects who were iftted with volar or dorsal hand splints performed grasp-release movements. Regions of interest were placed on the primary motor cortex (M1), primary somatosensory cortex (S1), posterior parietal cortex (PPC), and secondary somato-sensory cortex (S2). Results of group analysis of fMRI data showed that the total numbers of activated voxels in all ROIs were significantly higher during use of volar hand splint (3,376) compared with that (1,416) during use of dorsal hand splint. In each ROI, use of volar hand splint induced greater activation in all ROIs (M1:1,748, S1:1,455, PPC:23, and S2:150) compared with use of dorsal hand splint (M1:783, S1:625, PPC:0, and S2:8). The peak activated value was also higher during use of volar hand splint (t-value:17.29) compared with that during use of dorsal hand splint (t-value:13.11). Taken together, use of volar hand splint induced greater cortical activation relevant to somatosensory function than use of dorsal hand splint. This result would be important for the physiatrist and therapist to apply appropriate somatosensory input in patients with brain injury. 相似文献
993.
目的:探讨节段和短段刺激尺神经后不同节段复合肌肉动作电位(CMAP)负波各参数变化及传导阻滞在吉兰-巴雷综合征(GBS)和慢性炎性脱髓鞘性周围神经病(CIDP)中的意义。方法:20例GBS和12例CIDP患者行尺神经5点分段刺激(腕、肘下、肘上、腋和Erb's点)和短段刺激,记录CMAP负波波幅、时程和面积的变化,分析各参数与临床肌力的相关性。结果:在GBS中,尺神经CMAP负波的时程、波幅和面积的变化在Erb’s点到腕部的各节段中差异很大;波幅与面积的衰减与临床肌力呈高度相关(r=-0.905和-0.907);传导阻滞多见于近端和肘部,时程离散不明显。在CIDP中,各节段中的参数变化差异不大;远端波幅与临床肌力相关(r=0.586);传导阻滞在各节段均可出现,常伴明显的时程延长。结论:GBS和CIDP中尺神经CMAP负波的波幅、面积和时程3个参数,可从电生理角度帮助我们认识脱髓鞘疾病的特点。 相似文献
994.
Ryan L. Olson Christopher J. Brush Peter J. Ehmann Brandon L. Alderman 《Clinical neurophysiology》2017,128(6):903-913
Objective
The aim of this study was to examine the effects of an 8-week moderate-intensity aerobic exercise training intervention on cognitive control in individuals with major depressive disorder (MDD).Methods
Participants with a current diagnosis of MDD (n = 30; 21.1 ± 2.0 years) were stratified by depressive symptoms and randomized to an 8-week intervention of aerobic exercise (AE) or placebo exercise (PE). AE consisted of three sessions/week of moderate-intensity exercise training while PE consisted of three sessions/week of light-intensity stretching. Cognitive control was assessed pre- and post-treatment using behavioral performance (i.e., reaction time and accuracy) and event-related potentials (i.e., N2 amplitude). Depressive symptoms and rumination were also assessed before and after the intervention.Results
Compared with PE, the AE treatment arm was associated with an increase in N2 amplitude to incongruent flanker task trials, reflecting an increase in cognitive control processes. Symptoms of depression also decreased after AE although the treatments did not differ in their effects on rumination. Exploratory mediation analysis indicated that changes in N2 amplitude did not mediate pre-to-post treatment reductions in depressive symptoms.Conclusions
An 8-week moderate-intensity AE program is associated with improved neural indices of conflict monitoring and reduced depressive symptoms among individuals with MDD.Significance
Future research examining the influence of exercise in combination with behavioral and pharmacological treatments for neurocognitive function in MDD is warranted. 相似文献995.
Timm Rosburg 《Clinical neurophysiology》2018,129(10):2099-2111
Objective
The study sought to assess the presence of auditory N100 gating deficits in patients with schizophrenia by meta-analysis.Methods
Literature was screened for studies on patients with schizophrenia that used the paired-click paradigm and reported N100 data. Both electroencephalographic and magnetoencephalographic studies were considered. N100 gating measures as well as the N100 amplitudes to the initial and repeated stimulus were extracted and subjected to a meta-analysis.Results
The literature research revealed 29 studies, reporting either N100 gating or N100 amplitude measures in paired-click experiments. Patients with schizophrenia exhibited less N100 gating than healthy controls across studies (mean g?=??0.405, SE?=?0.051). However, what appeared as a gating deficit in patients was due to reduced N100 amplitudes to the initial stimulus in this group (mean g?=?0.610, SE?=?0.075). Patients and controls did not differ in their N100 amplitudes to the repeated stimulus (mean g?=?0.042, SE?=?0.066).Conclusion
There is no evidence for an auditory N100 gating deficit in schizophrenia, but for an impaired N100 response recovery.Significance
Previous findings on impaired N100 gating in schizophrenia patients reflect deficient processing of auditory salience rather than defective inhibition of repeating redundant auditory stimulation. 相似文献996.
目的 :了解颅内压 (ICP)增高对脑血循环及脑电生理的影响。方法 :对 86例高颅压患者治疗前、后的经颅多普勒超声、体感诱发电位、脑压及血压进行对比研究。结果 :ICP轻度升高脑血流速度增快 ,ICP中重度升高血流速度迅速减慢 ;SEP各波潜伏期延长 ,波幅降低 ,以N2 0 最明显。结论 :ICP与PI、RI、潜伏期、波幅有显著相关性 ,TCD及SEP所测得参数改变可间接推断ICP变化 ,并有助于病情及预后的判断 相似文献
997.
Xi Chen Aya Haggiagi Efstathia Tzatha Lisa M. DeAngelis Bianca Santomasso 《Clinical neurophysiology》2019,130(8):1440-1445
ObjectiveTo report the electrodiagnostic features of immune checkpoint inhibitor (ICI)-related neuropathy.MethodsWe retrospectively reviewed clinical presentations and electrodiagnostic features of 23 patients studied after receiving immune checkpoint inhibitors (ICIs). The presentations for electrodiagnostic evaluation included an acute neuropathy or neuromuscular junction disorder. We applied established electrodiagnostic criteria for polyneuropathy and acute demyelinating neuropathy.ResultsWe identified acute demyelinating neuropathy (13 cases), axonal sensory motor neuropathy (5), pure sensory neuropathy (4) and mononeuropathy (1). 13 patients had acute demyelinating neuropathy confirmed by demonstrating demyelination in 2 or more nerves; 3 additional patients had demyelination in only one nerve. Analysis of motor nerve conduction parameters revealed demyelination involving median and ulnar nerve distal motor latencies as well as median, ulnar and peroneal nerve conduction velocities. Conduction block was found in median, ulnar and peroneal nerves. The remaining one-third patients without demyelination had acute painful axonal neuropathy. Coexisting myopathic changes (6) and neuromuscular junction dysfunction (4) were also identified.ConclusionsOur findings suggest that, while immune-mediated motor nerve demyelination is the primary underlying mechanism of ICI-related neuropathy, axonal painful neuropathy can also be an important presentation. Early recognition and effective intervention may reduce morbidity and permanent disability.SignificanceElectrophysiological studies might be useful in the evaluation of ICI-related neuropathy. 相似文献
998.
Dynamical entrainment of corticospinal excitability during rhythmic movement observation: a Transcranial Magnetic Stimulation study 下载免费PDF全文
Manuel Varlet Giacomo Novembre Peter E. Keller 《The European journal of neuroscience》2017,45(11):1465-1472
Spontaneous modulations of corticospinal excitability during action observation have been interpreted as evidence for the activation of internal motor representations equivalent to the observed action. Alternatively or complementary to this perspective, growing evidence shows that motor activity during observation of rhythmic movements can be modulated by direct visuomotor couplings and dynamical entrainment. In‐phase and anti‐phase entrainment spontaneously occur, characterized by cyclic movements proceeding simultaneously in the same (in‐phase) or opposite (anti‐phase) direction. Here we investigate corticospinal excitability during the observation of vertical oscillations of an index finger using Transcranial Magnetic Stimulation (TMS). Motor‐evoked potentials (MEPs) were recorded from participants’ flexor and extensor muscles of the right index finger, placed in either a maximal steady flexion or extension position, with stimulations delivered at maximal flexion, maximal extension or mid‐trajectory of the observed finger oscillations. Consistent with the occurrence of dynamical motor entrainment, increased and decreased MEP responses – suggesting the facilitation of stable in‐phase and anti‐phase relations but not an unstable 90° phase relation – were found in participants’ flexors. Anti‐phase motor facilitation contrasts with the activation of internal motor representation as it involves activity in the motor system opposite from activity required for the execution of the observed movement. These findings demonstrate the relevance of dynamical entrainment theories and methods for understanding spontaneous motor activity in the brain during action observation and the mechanisms underpinning coordinated movements during social interaction. 相似文献
999.
Tommaso Fedele Claudio Schönenberger Gabriel Curio Carlo Serra Niklaus Krayenbühl Johannes Sarnthein 《Clinical neurophysiology》2017,128(10):1851-1857
Objective
The detectability of high frequency oscillations (HFO, >200 Hz) in the intraoperative ECoG is restricted by their low signal-to-noise ratio (SNR). Using the somatosensory evoked HFO, we quantify how HFO detectability can benefit from a custom-made low-noise amplifier (LNA).Methods
In 9 patients undergoing tumor surgery in the central region, subdural strip electrodes were placed for intraoperative neurophysiological monitoring. We recorded the somatosensory evoked potential (SEP) simultaneously by custom-made LNA and by a commercial device (CD). We varied the stimulation rate between 1.3 and 12.7 Hz to tune the SNR of the N20 component and the evoked HFO and quantified HFO detectability at the single trial level. In three patients we compared Propofol® and Sevoflurane® anesthesia.Results
In the average, amplitude decreased in both in N20 and evoked HFO amplitude with increasing stimulation rate (p < 0.05). We detected a higher percentage of single trial evoked HFO with the LNA (p < 0.001) for recordings with low impedance (<5 kΩ). Average amplitudes were indistinguishable between anesthesia compounds.Conclusion
Low-noise amplification improves the detection of the evoked HFO in recordings with subdural electrodes with low impedance.Significance
Low-noise EEG might critically improve the detectability of interictal spontaneous HFO in subdural and possibly in scalp recordings. 相似文献1000.
Somatosensory evoked potentials (SSEPs) and F-wave responses were compared after tibial (PTN) and median (MN) nerve stimulation in patients with acute inflammatory demyelinating polyradiculoneuropathy (AIDP). Nineteen patients were evaluated within 2 weeks of AIDP onset. Each had F-wave and PTN-SSEP studies; 18 had MN-SSEP studies. Ten patients had absent or prolonged MN-SSEP latencies, whereas 16 had abnormal MN F-wave studies. Seventeen patients had an abnormal PTN-SSEP while 12 had abnormal PTN F waves. Every patient with an abnormal MN-SSEP also had an abnormal PTN-SSEP. The most common PTN-SSEP findings were an absent or prolonged latency of N8 or N22. All patients had either an abnormal MN F wave or PTN-SSEP. 相似文献