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1.
诱发电位的提取通常依靠相干平均方法,需要进行多次的重复刺激,实验时间较长.随着实验时间的增加,受试者生理因素及环境因素的变化,会影响诱发电位的正常形态(波形、强度和相位).利用独立分量分析和小波变换方法,通过时域信息和空域信息的综合应用,可成功提取到听觉诱发电位晚成分的强度在实验过程中的变化,对由于实验时间增加对晚成分的影响做出定量评价.结果表明,在10 min左右的实验过程中,听觉诱发电位晚成分的幅度会下降约40%.  相似文献   

2.
提出一种基于参数模型的信息处理方法,用于诱发脑电的提取,这种方法可以得到单次EP波形的无偏,最小方差估计,用刺激强度实验验证了该方法在实际情况下的有效,进一步将其应用于刺激前EEG与EP的关联研究,得到了刺激前40Hz的EEG成分与晚潜伏期听觉诱发脑电幅度有极显著负相关的结果,表明刺激前及状态确定对EP有影响。  相似文献   

3.
刺激强度、刺激音持续时间与脑干听觉诱发电位慢成分的关系郑辉,李善民(暨南大学医学院听觉生理学研究室广州510632)脑干听觉诱发电位(BAEP)是听觉诱发电位的早期成分,由听觉刺激后10ms内所记录到的7个阳性快波所组成,该波群重叠在缓慢的阳性慢波上...  相似文献   

4.
本文提出了一种新型有效的基于听觉模型的基音提取方法.它主要是模拟人类听觉系统音调感知功能,在跨通道累加自相关处理方法的基础上,增加了神经系统在感知时的时间连续性模拟,由于对空间和时间分布的信息的综合累加作用,使所提的方法不仅能提取出淹没在各种噪音下的语言信号的基音信息,而且能够判断所处理信号是否由重叠语言信号构成,并进一步提取出叠在一起的独立的基音信息.初步的实验结果证明了所提模型的有效性.  相似文献   

5.
提出一种基于参数模型的信号处理方法,用于诱发脑电(EP)的提取,这种方法可以得到单次EP波形的无偏、最小方差估计。用刺激强度实验验证了该方法在实际情况下的有效,进一步将其应用于刺激前EEG与EP的关联研究,得到了刺激前40Hz的EEG成分与晚潜伏期听觉诱发脑电幅度有极显著负相关的结果,表明刺激前及状态确定对EP有影响。  相似文献   

6.
基于TDT神经电生理软硬件平台和Matlab软件环境,开发了专用于听觉电生理研究的实时分析软件。通过对神经元胞外记录信号的在线处理和分析,可以在实验过程中得到刺激后放电活动时间直方图、平均发放率、首次发放潜伏期等定量分析结果,以及刺激参数变化时神经元发放率的变化曲线,如发放率-刺激强度曲线等。此分析软件被用于大鼠下丘神经元听觉信息编码的研究中,观察到下丘神经元对于纯音和噪声刺激不同的时间响应模式,以及神经元发放率和首次发放潜伏期对声音刺激强度的编码。  相似文献   

7.
选用18d、38d、成鸟(3月以上)三种年龄的雄性虎皮鹦鹉作为实验材料,采用测量脑干听觉诱发电位和制作内耳的石蜡切片两种方法,研究了鸟类在发育时期耳蜗感觉上皮细胞的变化以及听觉功能的发育状况。鸟的听觉能力在出生后不断得到提高,38d基本达到成鸟的水平;耳蜗毛细胞的形态、内部结构逐渐趋于成熟,其灵敏度不断提高,感受听觉的能力也在增强,38d基本与成鸟的发育程度相同。耳蜗感觉上皮细胞的发育对听觉行为产生的时间和发展具有极为重要的影响。  相似文献   

8.
本文提出了关于听觉诱发电位早成分的一种统一理论和模型,并通过实验和计算机仿真的比较进行了检验.  相似文献   

9.
兔脑温升高时视觉诱发电位的变化*陈晓玲李清君李文斌郝振海董承统(河北医科大学基础医学研究所,石家庄050017)以往我们用选择性升高脑温的方法观察了兔听觉诱发电位的变化,本实验观察视觉诱发电位(Visualevokedpotentials,VEPs)...  相似文献   

10.
鸟类脑干听觉诱发电位的观察   总被引:1,自引:0,他引:1  
采用短声刺激鸟类听觉感受器的方法,对15只健康成年虎皮鹦鹉的脑干听觉诱发电位进行了实验观察。结果发现,鸟类头顶均能记录到与听觉有关的脑干听觉诱发电位Ⅰ波、Ⅱ波、Ⅲ波、Ⅳ波和Ⅴ波。为鸟类语言发声研究的听力学评价提供一个简便可行的方法。  相似文献   

11.
有关猫听觉脑干电反应(ABR)两耳干涉作用的研究   总被引:4,自引:1,他引:3  
用不同声强稳态白噪声和短声同时分别刺激两耳,观察白噪声负荷侧耳蜗破坏前后另一侧ABR的改变,探讨两耳干涉作用及其可能的机制。结果显示,对侧耳蜗破坏前,40dB和75dB白噪声对0dB、45dB、70dB和75dBSPL的短声诱发的ABR各波振幅均有明显影响(P<0.050.01)。耳蜗破坏后,同样条件下记录的ABR振幅基本无明显变化(P>0.05)。提示白噪声对短声有一定的干涉作用。短声为70dBSPL时ABRP1波振幅的减小可能与中枢离中控制相关。  相似文献   

12.
实验在66只麻醉、制动,断双侧颈迷走神经和人工通气的家兔上进行。通过微量注射神经元胞体兴奋剂谷氨酸钠和神经元胞体抑制剂甘氨酸,改变孤束核腹外侧区神经元兴奋活动,探讨对下丘脑弓状核诱发电位的影响及其可能的机制和意义。实验结果如下:(1)孤束核腹外侧区微量注射谷氨酸钠,可使膈神经放电显著增加和使弓状核诱发电位P2及N2波幅显著降低;而微量注射甘氨酸则使膈神经放电显著减少和使弓状核诱发电位P2及N2波幅显著增大。(2)静脉注射纳洛酮对谷氨酸钠引起的膈神经放电兴奋效应无明显影响,但能翻转谷氨酸钠对弓状核诱发电位P2及N2波幅的抑制效应。提示:孤束核腹外侧区呼吸神经元的兴奋活动可扩散至弓状核,并对弓状核诱发电位产生影响,此影响可能是由内源性阿片系统参与而实现的。  相似文献   

13.
Acute kidney injury (AKI) is a common and severe clinical condition with high morbidity and mortality. Ischaemia‐reperfusion (I/R) injury remains the major cause of AKI in the clinic. Ferroptosis is a recently discovered form of programmed cell death (PCD) that is characterized by iron‐dependent accumulation of reactive oxygen species (ROS). Compelling evidence has shown that renal tubular cell death involves ferroptosis, although the underlying mechanisms remain unclear. Augmenter of liver regeneration (ALR) is a widely distributed multifunctional protein that is expressed in many tissues. Our previous study demonstrated that ALR possesses an anti‐oxidant function. However, the modulatory mechanism of ALR remains unclear and warrants further investigation. Here, to elucidate the role of ALR in ferroptosis, ALR expression was inhibited using short hairpin RNA lentivirals (shRNA) in vitro model of I/R‐induced AKI. The results suggest that the level of ferroptosis is increased, particularly in the shRNA/ALR group, accompanied by increased ROS and mitochondrial damage. Furthermore, inhibition of system xc‐ with erastin aggravates ferroptosis, particularly silencing of the expression of ALR. Unexpectedly, we demonstrate a novel signalling pathway of ferroptosis. In summary, we show for the first time that silencing ALR aggravates ferroptosis in an in vitro model of I/R. Notably, we show that I/R induced kidney ferroptosis is mediated by ALR, which is linked to the glutathione‐glutathione peroxidase (GSH‐GPx) system.  相似文献   

14.
用电生理学方法研究了灭多威对美洲大蠊Periplanetaamerwana腹六神经节(A6节)突触传递的影响。用灭多威溶液浸泡A6节,电刺激尾须神经粗支,用甘露醇间隙法记录兴奋性突触后电位(EPSP)和突触后动作电位。给予弱刺激只记录到EPSP时,灭多威作用初期EPSP幅度增加、时程延长,能诱发突触后动作电位,随后EPSP逐渐减小至消失,冲洗可恢复,突触前反应保持不变。增加电刺激强度记录到突触后动作电位时,灭多威可阻断A6节的突触传递,阻断时间是浓度依赖性的,阻断是可逆的,但冲洗30 min仍保留一定的后作用。对美洲大蠊雄性成虫腹腔注射灭多威测定致死中量(LD50)为(3.56±0.01) μg/g体重。根据灭多威的作用机理对其阻断A6节突触传递的特点以及对虫体的毒杀机制进行了讨论。  相似文献   

15.
范先群  奚渭清 《生理学报》1996,48(5):497-500
用系列强度11档刺激闪光记录20例30只眼的视网膜电图(ERG)振荡电位(OP),研究OP的光强特性和参数稳定性。结果表明,OP各子波峰时和刺激光强呈指数曲线相关,相关性很高;而振幅和光强的函数关系的变异很大,相关性较低,不同对象间OP各子波振幅的变异系数较大,而峰时的变异系数较小,OP的峰时改变比振幅改变更为稳定。  相似文献   

16.
在用事件相关电位(event-related potentials,ERP)研究视觉空间注意问题时,直接观察ERP数据就可得出,空间注意的主要作用是对视觉信息处理的调制,它出现在刺激开始后大约80~250ms,主要表现为枕叶的P1、N1和P2波有明显的增强但它们的潜伏期没有变化。采用基于协同学的时空模式分解方法,把视觉空间注意ERP分解为3个模式成分。结果表明,注意不仅使模式1的第一个正波成分(P11)、第一个负波成分(N11)以及第二个正波成分(P12)增强,还使模式3的第一个正波成分(P31)的潜伏期缩短。用探照灯模型对这些现象作了初步解释,说明该方法是研究注意ERP的一种有潜力的新方法。  相似文献   

17.
Pilot studies demonstrate evidence that the electrophysiological processes associated with flash stimulation of the central nervous system (CNS) of rats, as seen in the recordings of visual-evoked potentials, may also be detectable using an ultrahigh frequency electromagnetic field (UHFEMF). Patterns of amplitude modulation of an applied UHFEMF, when recorded and averaged, show strong correlations with simultaneously recorded evoked potentials. The data support the hypothesis that the UHFEMF amplitude is altered in a dynamic fashion by the tissue's electrophysiological processes that are involved with the generation of CNS electric fields.  相似文献   

18.
The spatial analysis of the potentials of single motor units of the rat medial gastrocnemius muscle evoked by stimulation of the fibres of split ventral roots was carried out with a bipolar electrode moving in the direction perpendicular to the longitudinal axis of the muscle fibres. During this movement of the electrode a variability was observed in the time of the biphasic potential from its maximum to minimum, and in the peak-to-peak amplitude of these potentials. The potentials recorded outside the territory of the motor unit had a lower amplitude in relation to the potentials from the territory of the unit. This made localization of the motor unit on the cross-section of the muscle possible. Differences in the duration of the potential from maximal to minimal amplitude (maximum-minimum amplitude time--M-MAT) of each investigated motor unit from successive recording sites reflected the number of fibres contributing to the action potential and the distance of the recording surface of the electrode from the zone of the motor end-plates of this motor unit. The greatest diameter of the territory of the observed motor units reached 2.5 mm.  相似文献   

19.
When auditory nerve function is lost due to surgical removal of bilateral acoustic tumors, a sense of hearing may be restored by means of an auditory brain-stem implant (ABI), which electrically stimulates the auditory pathway at the level of the cochlear nucleus. Placement of the stimulating electrodes during surgical implantation may be aided by electrically evoked auditory brain-stem responses (EABRs) recorded intra-operatively. To establish preliminary standards for human EABRs evoked by electrical stimulation of the cochlear nucleus, short-latency evoked potentials were recorded from 6 ABI patients who were either already implanted or undergoing implantation surgery. Neural responses were distinguished from stimulus artifact and equipment artifact by their properties during stimulus polarity reversal and amplitude variation. Other properties contributed to further identification of the evoked potentials as auditory responses (EABRs). The response waveforms generally had 2 or 3 waves. The peak latencies of these waves (approximately 0.3, 1.3, and 2.2 msec) and the brain-stem localization of the region from which they could be elicited are consistent with auditory brain-stem origin.  相似文献   

20.
迷走神经感觉输入诱发的鲫鱼Mauthner细胞胞内电位变化   总被引:5,自引:0,他引:5  
Liu LM  Xie Y  Yu F  Zhang MX 《生理学报》2001,53(4):252-256
实验运用微电极穿刺技术,初步探索了刺激鲫鱼右侧迷走神经在双侧Mauthner(M)细胞胞体诱发的胞内电位变化。结果表明:(1)直接刺激鲫鱼右侧迷走神经,可在同侧或对侧M细胞胞体记录到一种短潜伏期、长持续时间、分级的、复合的突触后电位(postsynaptic potentials,PSPs)。此PSPs表现出明显的强度依从性和频率依赖性。(2)刺激迷走神经诱发的PSPs可使逆向锋电位的幅度降低。(3)肌注士的宁后,PSPs的幅度增高、平均持续时间增加、峰值前移。并且可爆发两个以上的动作电位,上述结果提示:迷走神经到M细胞的通路可能 是由长短不等的神经链群组成的。且此通路中不仅包含有兴奋性成分还包含有抑制性成分,而兴奋和抑制之间的相互关系可能起着调节M细胞兴奋性的作用。  相似文献   

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