小脑卒中后非运动功能障碍的研究进展

目前对小脑非运动功能的新认识是基于神经解剖学、神经影像学和临床研究的综合证据,临床上对其认识不足,因此小脑卒中患者的非运动功能损害症状常常被忽视。目前研究认为小脑的非运动功能主要包括认知、语言及情绪、情感等方面。本文主要从解剖、小脑非运动功能的神经调控模式和临床表现等方面对小脑卒中后非运动功能障碍的研究进展进行阐述。     

小脑在血管性认知功能障碍中的作用

小脑不仅与运动有关,而且也参与非运动的认知功能。血管性认知功能障碍是认知功能疾病中的一个重要分支,其主要与脑血管病危险因素及高龄有关。脑组织缺血导致的神经细胞及神经纤维束损害是血管性认知功能损害的主要发病机制,其关键部位在额叶（尤其是前额区）、前扣带回、海马回、下丘脑、基底节、顶叶（特别是优势半球角回）和颞叶等,这些部位多数与小脑存在纤维联系。本文综述了近年来对小脑各部分组件式结构和功能,及其与血管性认知功能损害关系等方面的研究,探讨小脑在血管性认知功能损害中的作用。     

小脑与认知功能关系的研究

在以往的研究中,大多关注的是小脑的运动控制与协调功能。近十年来,小脑参与工作记忆、语言、视空间、执行处理等高级认知和情感功能逐渐成为研究的热点。小脑和大脑之间存在广泛的双向联系,形成了重要的认知功能环路;小脑通过该环路对大脑的认知功能脑区进行调控。本文就小脑参与高级认知功能的神经解剖和功能基础以及主要相关认知领域进行综述。     

默认网络与精神分裂症关系的研究进展北大核心CSCD

精神分裂症是一类严重的神经精神性疾病,多起病于青壮年,病程缓慢迁延,主要表现为基本个性改变,思维、知觉、情感和行为的分裂,精神活动与环境的不协调等,同时存在认知功能的缺陷.精神分裂症的核心症状被认为是多个分散脑区的功能无法进行有效整合[1],其病因尚未明确.神经心理学和神经影像学研究显示,精神疾病存在广泛的脑部损害,表现为脑区功能活动、功能连接上的异常.大量研究报道了精神分裂症患者默认网络的异常,推测默认网络的紊乱在精神分裂症的病理机制中有着重要作用,且与该病的认知缺陷、临床表现等相关.近年来神经影像学技术的快速发展,使得我们能更全面地了解和探索精神分裂症患者默认网络的异常,我们就近年这方面研究作一综述.     

精神疾病中小脑的影像学研究进展

小脑既往被认为只参与了机体的运动和平衡调节,近年研究发现,小脑还参与了认知、情感、行为等脑部高级生理功能的调节过程,在精神分裂症、抑郁症、双相障碍等临床常见精神疾病的发病过程中起到一定作用.本文拟就相关精神疾病的小脑影像学研究成果做一简要回顾.     

小脑的认知及语言功能探讨

小脑的认知及语言功能探讨曹莉颜振瀛高素荣近两个世纪以来，人们一直认为小脑只具有运动功能，如维持身体的平衡、调解肌张力和协调运动。但近年来的研究表明，小脑也具有非运动功能，如认知及语言功能。其解剖基础为小脑进化中最新的部分即小脑外侧部。现根据近年来国外...     

基于脚桥核神经网络的帕金森病冻结步态的机制探讨

目的探讨脚桥核(PPN)神经网络在帕金森病(PD)冻结步态(FOG)中的作用及其变化规律。方法对16例PD伴冻结步态(PD FOG+)患者,17例PD不伴冻结步态(PD FOG-)患者及17名正常对照者,行静息态功能MRI(rs-fMRI)扫描,并用功能连接方法对结果进行分析;同时行DTI检查,对脑白质纤维DTI的各相关参数进行组间比较。结果与正常对照组及PD FOG-组相比,PD FOG+组与PPN功能连接异常的脑区主要分布在皮质-脑桥核-小脑通路以及视觉相关颞叶皮质;与正常对照组相比,PD FOG+组存在明显的脑白质结构异常改变,包括连接两侧大脑半球的胼胝体、连接皮质-皮质间的白质纤维束、连接皮质-皮质下结构的白质纤维束以及连接丘脑的白质纤维束。结论 PD FOG+患者存在异常的PPN功能连接网络,主要影响皮质-脑桥核-小脑通路和参与视觉信息处理的颞叶相关皮质,并有显著的脑白质结构异常改变,可涉及运动、感觉和认知传导相关通路。如结合rs-fMRI和DTI技术,可以进一步提高对PD FOG潜在发病机制的认识。     

小脑靶向神经刺激促进吞咽恢复机制的研究进展

大脑的经颅磁刺激和电刺激是目前具有一定应用前景的技术,逐渐在基础研究和临床实 践中得到应用。这种无创的、非侵入性的靶向神经刺激,通过调节神经兴奋性和可塑性来改善或恢复 大脑功能。由于小脑在运动协调、联想和情感等方面与大脑存在神经解剖和功能联系,因此以小脑为 靶点的神经刺激可以更好地了解生理及病理状态下,小脑与大脑吞咽运动区之间的联系,更好地研究 小脑对吞咽皮质区域兴奋性的调节作用,以及对吞咽功能的影响,为神经源性吞咽障碍提供一种潜在 的治疗方法。     

小脑与卒中后运动学习关系的研究进展

运动学习强调引导患者主动练习缺失的运动功能,获得尽可能接近正常的运动技能,这 种学习过程由小脑和大脑皮层的共同作用来完成。卒中后的功能恢复是运动再学习的过程,康复锻 炼的一个重要机制是基于细胞可塑性的运动学习,而小脑在运动学习过程中发挥着不可替代的作用。 神经生理学研究表明,小脑中参与运动学习最主要的细胞是浦肯野细胞和颗粒细胞。小脑-皮质通 路涉及运动控制和运动学习,使得小脑成为神经调节和治疗卒中后运动障碍的重要靶点。本文就小 脑运动学习的细胞机制和针对小脑的刺激技术对卒中后运动功能恢复的作用进行综述。     

青少年肌阵挛癫痫的小脑半球功能连接分析

目的探讨青少年肌阵挛癫痫(JME)患者的小脑半球与大脑的功能连接特征。方法采用横断面研究方法,选取2014年3月-2015年12月在成都市新华社区卫生服务中心和成都市第一人民医院就诊的JME患者25例(患者组),同期纳入26名健康对照者(对照组)。利用GE 3.0T磁共振采集两组静息态功能磁共振(fMRI)图像,对双侧小脑半球的18个感兴趣区域(ROI)分别进行与大脑的功能连接,分析JME患者各个感兴趣区与大脑功能连接的改变。结果①两组年龄、性别差异均无统计学意义(P均0.05)。②JME患者的小脑半球与颞、枕叶功能连接高于健康对照组,而与额叶、默认模式网络(DMN)以及运动相关脑区的功能连接低于健康对照组,差异均有统计学意义(P均0.05)。结论小脑与额叶的功能连接降低,可能与临床上JME患者额叶高波幅放电有关,同时小脑与运动相关脑区的功能连接降低可能与JME患者的运动功能异常有关。     

Sense of coherence as a predictor of subjective state of health: results of 4 years of follow-up of adults

A number of cross-sectional population studies have shown that a strong sense of coherence (SOC) is associated with various aspects of good perceived health. The association does not seem to be entirely attributable to underlying associations of SOC with other variables, such as age or level of education. OBJECTIVE: The aim of the study reported here was to determine whether SOC predicted subjective state of health. METHODS: The study was carried out as a two-way panel mail survey of 1976 individuals with 4 years interval for two collections of data. The statistical method used was multivariate cumulative logistic modeling. Age, initial subjective state of health, initial occupational training level, and initial degree of social integration were included as potential explanatory variables. RESULTS: A strong SOC predicted good health in women and men. CONCLUSIONS: SOC can be interpreted as an autonomous internal resource contributing to a favorable development of subjective state of health. SOC data should, however, be regarded as complementary to and not a substitute for information already known to be associated with increased risk of future ill health.     

Denervation study of synapses of organ of corti of old world monkeys

Fine structural characteristics of synapses in the spiral organ of Corti were examined, with reference to differences between inner and outer haircell systems, and to location of neurons of origin of efferent axons. Surgical interruption of crossed olivocochlear bundle, of vestibular nerve, of facial nerve, and excision of superior cervical ganglia were used to determine the pathways of efferent axons. Interruption of the vestibular nerve near the brainstem results in degeneration of all efferent terminals on outer hair cells. Mid-line lesions at, and caudal to, the facial colliculus result in degeneration of about half of these efferent terminals. Efferent synaptic bulbs to the inner hair-cell system are small, of the order of one micron, and form type 2 junctions with afferent dendrites. They tend to have more large dense-core vesicles (about 80 nm) than the large efferent terminals of the outer hair-cell system, and appear to be the terminals of axons in the habenula perforata, which exhibit varicosities laden with large dense core vesicles. The varicosities are unaffected by excision of the superior cervical ganglia. So far as our material can reveal, it appears that the varicosities in the habenula perforata do not survive vestibular root interruption, nor do the efferent processes in the internal spiral bundle or at the base of inner hair cells. Most interestingly, the afferent processes of the inner hair-cell system, as identified for example by their relation to pre-synaptic bodies in the inner hair cells, are subject to a trans-synaptic reaction after severance of the vestibular root. They undergo a dramatic cytological transformation, characterized by increase of volume, engorgement with microtubules, microfilaments, microvesicles of various sizes, and clusters of lysosomes. Thus, both the efferent and afferent terminals of the inner hair-cell system show marked cytological differences from the corresponding terminals of the outer hair cell system.     

Mechanism of action of tubocurarine on nicotinic cholinoreceptors of neurons of the sympathetic ganglia of rats

Tubocurarine (Tc) effect on membrane currents elicited by acetylcholine (ACh) was studied in isolated superior cervical ganglion neurons of rat using patch-clamp method in the whole-cell recording mode. The "use-dependent" block of ACh current by Tc was revealed in the experiments with ACh applications, indicating that Tc blocked the channels opened by ACh. Mean lifetime of Tc-open channel complex, tau, was found to be 9.8 +/- 0.5 s (n = 7) at -50 mV and 20-24 degrees C. tau exponentially increased with membrane hyperpolarization (e-fold change in tau corresponded to the membrane potential shift by 61 mV). Inhibition of the ACh-induced current by Tc (3-30 microM/1) was completely abolished by membrane depolarization to the level of 80-100 mV. Inhibition of ACh-induced current was augmented at increased ACh doses. It is concluded that the open channel block produced by Tc is likely to be the only mechanism for Tc action on nicotinic acetylcholine receptors in superior cervical ganglion neurons of rat.     

The effect of age of onset of PD on risk of dementia

Background Dementia occurs in the majority of patients with Parkinson’s disease (PD). Late onset of PD has been reported to be associated with a higher risk for dementia. However, age at onset (AAO) and age at baseline assessment are often correlated. The aim of this study was to explore whether AAO of PD symptoms is a risk factor for dementia independent of the general effect of age. Methods Two community-based studies of PD in New York (n = 281) and Rogaland county, Norway (n = 227) and two population-based groups of healthy elderly from New York (n = 180) and Odense, Denmark (n = 2414) were followed prospectively for 3–4 years and assessed for dementia according to DSM-IIIR. All PD and control cases underwent neurological examination and were followed with neurological and neuropsychological assessments. We used Cox proportional hazards regression based on three different time scales to explore the effect of AAO of PD on risk of dementia, adjusting for age at baseline and other demographic and clinical variables. Findings In both PD groups and in the pooled analyses, there was a significant effect of age at baseline assessment on the time to develop dementia, but there was no effect of AAO independent of age itself. Consistent with these results, there was no increased relative effect of age on the time to develop dementia in PD cases compared with controls. Interpretation This study shows that it is the general effect of age, rather than AAO that is associated with incident dementia in subjects with PD. Received in revised form: 22 December 2005