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1.
《Brain stimulation》2020,13(5):1284-1295
BackgroundElectroconvulsive therapy (ECT) technique is often changed after insufficient improvement, yet there has been little research on switching strategies.ObjectiveTo document clinical outcome in ECT nonresponders who were received a second course using high dose, brief pulse, bifrontotemporal (HD BP BL) ECT, and compare relapse rates and cognitive effects relative to patients who received only one ECT course and as a function of the type of ECT first received.MethodsPatients were classified as receiving Weak, Strong, or HD BP BL ECT during three randomized trials at Columbia University. Nonresponders received HD BP BL ECT. In a separate multi-site trial, Optimization of ECT, patients were randomized to right unilateral or BL ECT and nonresponders also received further treatment with HD BP BL ECT.ResultsRemission rates with a second course of HD BP BL ECT were high in ECT nonresponders, approximately 60% and 40% in the Columbia University and Optimization of ECT studies, respectively. Clinical outcome was independent of the type of ECT first received. A second course with HD BP BL ECT resulted in greater retrograde amnesia immediately, two months, and six months following ECT.ConclusionsIn the largest samples of ECT nonresponders studied to date, a second course of ECT had marked antidepressant effects. Since the therapeutic effects were independent of the technique first administered, it is possible that many patients may benefit simply from longer courses of ECT. Randomized trials are needed to determine whether, when, and how to change treatment technique in ECT.  相似文献   
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《Clinical neurophysiology》2020,131(1):213-224
ObjectiveSystematically review the abnormalities in event related potential (ERP) recorded in Rett Syndrome (RTT) patients and animals in search of translational biomarkers of deficits related to the particular neurophysiological processes of known genetic origin (MECP2 mutations).MethodsPubmed, ISI Web of Knowledge and BIORXIV were searched for the relevant articles according to PRISMA standards.ResultsERP components are generally delayed across all sensory modalities both in RTT patients and its animal model, while findings on ERPs amplitude strongly depend on stimulus properties and presentation rate. Studies on RTT animal models uncovered the abnormalities in the excitatory and inhibitory transmission as critical mechanisms underlying the ERPs changes, but showed that even similar ERP alterations in auditory and visual domains have a diverse neural basis. A range of novel approaches has been developed in animal studies bringing along the meaningful neurophysiological interpretation of ERP measures in RTT patients.ConclusionsWhile there is a clear evidence for sensory ERPs abnormalities in RTT, to further advance the field there is a need in a large-scale ERP studies with the functionally-relevant experimental paradigms.SignificanceThe review provides insights into domain-specific neural basis of the ERP abnormalities and promotes clinical application of the ERP measures as the non-invasive functional biomarkers of RTT pathophysiology.  相似文献   
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《Clinical neurophysiology》2021,132(12):3104-3115
ObjectiveWe aimed to establish an objective neurophysiological test protocol that can be used to assess the somatosensory nervous system.MethodsIn order to assess most fiber subtypes of the somatosensory nervous system, repetitive stimuli of seven different modalities (touch, vibration, pinprick, cold, contact heat, laser, and warmth) were synchronized with the electroencephalogram (EEG) and applied on the cheek and dorsum of the hand and dorsum of the foot in 21 healthy subjects and three polyneuropathy (PNP) patients. Latencies and amplitudes of the modalities were assessed and compared. Patients received quantitative sensory testing (QST) as reference.ResultsWe found reproducible evoked potentials recordings for touch, vibration, pinprick, contact-heat, and laser stimuli. The recording of warm-evoked potentials was challenging in young healthy subjects and not applicable in patients. Latencies were shortest within Aβ-fiber-mediated signals and longest within C-fibers. The test protocol detected function loss within the Aβ-fiber and Aδ-fiber-range in PNP patients. This function loss corresponded with QST findings.ConclusionIn this pilot study, we developed a neurophysiological test protocol that can specifically assess most of the somatosensory modalities. Despite technical challenges, initial patient data appear promising regarding a possible future clinical application.SignificanceEstablished and custom-made stimulators were combined to assess different fiber subtypes of the somatosensory nervous system using modality-specific evoked potentials.  相似文献   
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〔摘 要〕 目的:观察长期服用抗精神病药物的精神疾病患者的脑电图异常检出率,对其影响因素进行分析,提出预防措施。 方法:选取 2020 年 6 月至 2020 年 12 月期间在泉州市第三医院住院的长期服用抗精神病药物患者 256 例进行脑电图检查, 统计检出异常率;并观察不同药物种类、不同年龄段、不同服药时间患者的脑电异常率,对脑电图异常的危险因素进行分析。 结果:256 例患者中 154 例(60.16 %)出现脑电图异常,其中轻度异常在临床中最常见,重度异常最少见。不同药物种类中, 氯氮平使用者脑电图异常率最高;不同年龄段中,年龄> 60 岁脑电图异常率较高。结论:长期服用抗精神病药物患者出现 脑电图异常的影响因素主要为年龄> 60 岁、长期服用氯氮平,故临床需结合患者年龄合理选择药物,尽量选择对脑电图影 响较小的药物,且密切监测患者病情变化,适当调整或优化治疗方案。  相似文献   
5.
We investigated changes of slow‐wave activity and sleep slow oscillations in the night following procedural learning boosted by reinforcement learning, and how these changes correlate with behavioural output. In the Task session, participants had to reach a visual target adapting cursor's movements to compensate an angular deviation introduced experimentally, while in the Control session no deviation was applied. The task was repeated at 13:00 hours, 17:00 hours and 23:00 hours before sleep, and at 08:00 hours after sleep. The deviation angle was set at 15° (13:00 hours and 17:00 hours) and increased to 45° (reinforcement) at 23:00 hours and 08:00 hours. Both for Task and Control nights, high‐density electroencephalogram sleep recordings were carried out (23:30?19:30 hours). The Task night as compared with the Control night showed increases of: (a) slow‐wave activity (absolute power) over the whole scalp; (b) slow‐wave activity (relative power) in left centro‐parietal areas; (c) sleep slow oscillations rate in sensorimotor and premotor areas; (d) amplitude of pre‐down and up states in premotor regions, left sensorimotor and right parietal regions; (e) sigma crowning the up state in right parietal regions. After Task night, we found an improvement of task performance showing correlations with sleep slow oscillations rate in right premotor, sensorimotor and parietal regions. These findings suggest a key role of sleep slow oscillations in procedural memories consolidation. The diverse components of sleep slow oscillations selectively reflect the network activations related to the reinforced learning of a procedural visuomotor task. Indeed, areas specifically involved in the task stand out as those with a significant association between sleep slow oscillations rate and overnight improvement in task performance.  相似文献   
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神经反馈是指通过脑机交互方式,将大脑活动转换成声音、图像、游戏等形式反馈给个体,以实现自主调节脑功能的目的。注意力是认知功能的重要方面,不仅是儿童发展成长的影响因素,也是成人日常生活中不可替代的重要心理品质。越来越多的实证研究已经发现神经反馈对健康个体的注意力具有调节作用,但缺乏对相关研究进展的总结和综述。综述基于大脑节律活动的神经反馈对于健康个体注意力调节作用的研究进展,分析注意力测量范式、学习者和非学习者的划分以及实验设计类型对神经反馈训练效果的影响,指出了追踪实验对研究的必要性。同时提及可用于健康个体注意力调节的其他几种神经反馈技术。期望为神经反馈提高注意能力的研究和实践提供参考。  相似文献   
9.
目的:通过研究急性脑梗死患者溶栓治疗前后的脑电信号特征,探讨样本熵算法在急性脑梗死溶栓治疗监测中的应用。方法:采用频谱和样本熵分析76例急性脑梗死患者在溶栓前和溶栓治疗后24 h的EEG数据。分析溶栓治疗前后的变化规律。结果:溶栓治疗有效的患者,Delta与Alpha频段的能量在溶栓治疗前后差异具有统计学意义(P<0.05);同时,溶栓前后,溶栓有效患者的Delta频段的样本熵在溶栓治疗前后的差异有统计学意义(P<0.001)。结论:Delta频段和Alpha频段的能量,以及样本熵可用于急性脑梗死溶栓治疗效果的监测评估。 【关键词】急性脑梗死;血栓溶解疗法;脑电图;频谱;样本熵  相似文献   
10.
传统基于脑电(EEG)的抑郁症研究将电极视为孤立节点,忽略了它们之间的关联性,难以发掘抑郁症患者异常大脑拓扑改变。为此,本文提出一种基于脑功能网络(BFN)的抑郁症识别框架,为避免容积导体效应,相位延迟指数用于构建BFN;以加权与二值化BFN信息互补为基础,选取"小世界"特性密切相关及最小生成树特定脑区BFN指标,采用递进式指标分析策略寻找抑郁症识别潜在标识物。本文以48名受试者静息态EEG数据用于验证方案,结果表明组间同步性在左颞、右顶枕、右额脑区明显改变;加权BFN最短路径长度和聚类系数,二值化BFN左颞和右额的叶子分数及右顶枕的直径与患者健康问卷9项(PHQ-9)之间具有相关性,且获得最高94.11%的识别率。此外,研究发现相对于健康对照者,抑郁症患者的信息处理能力明显下降。通过上述结论,期望本研究结果可为BFN构建与分析提供新的思路,为抑郁症识别潜在标识物的发掘提供新的方法。  相似文献   
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