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1.
在氨基甲酸乙酯麻醉的36只鸽上,记录和分析了丘脑背外后核对桡神经传入冲动发生反应的103个神经元的单位放电.神经元的诱发反应可分为六种类型.其中一部分单位还对刺激坐骨神经发生反应.不同前、后肢的同时传入可以在同一神经元上会聚并具有相互作用.丘脑背外后核的多种形式会聚可能是家鸽丘脑对四肢躯体感觉传入信息进行整合和加工的基础.  相似文献   

2.
实验在61只家鸽上完成。动物用三碘季胺酚麻痹,记录了前脑36个神经元的电活动。实验结果表明,对短声刺激具有反应的前脑神经元分散地分布在旧纹状体、上纹状体以及新纹状体内,但是大多数听神经元集聚在相当于Karten和Hodos氏鸽脑立体定位图谱P_(1~3),L或R_(1~3)以及H_(2~6)的坐标范围之内。这些对声刺激有反应的听神经元的潜伏期为5~42msec。在正常情况下,神经元的潜伏期很少变化。前脑听神经元既可以接受对侧耳的信息,也可以接受同侧耳的信息。在旧纹状体内来自双耳信息的聚合可能引起相互抑制的结果。  相似文献   

3.
实验在61只家鸽上完成。动物用三碘季胺酚麻痹,记录了前脑36个神经元的电活动。实验结果表明,对短声刺激具有反应的前脑神经元分散地分布在旧纹状体、上纹状体以及新纹状体内,但是大多数听神经元集聚在相当于Karten和Hodos氏鸽脑立体定位图谱P_(1-3),L或R_(1-3)以及H_(2-6)的坐标范围之内。这些对声刺激有反应的听神经元的潜伏期为5~42msec。在正常情况下,神经元的潜伏期很少变化。前脑听神经元既可以接受对侧耳的信息,也可以接受同侧耳的信息。在旧纹状体内来自双耳信息的聚合可能引起相互抑制的结果。  相似文献   

4.
用细胞外记录单位放电的方法观察了刺激大鼠扣带皮层前部(ACC)对初级体感皮层(Sm.Ⅰ)接受触压觉传入神经元诱发放电的影响,神经元的鉴别方法是外周神经碰撞试验和自然触压觉刺激验证,在所鉴别的45个神经元中,14个神经元的诱发放电受到了易化性影响,9个神经元的诱发放电受到了抑制性影响,扣带皮层前部影响的潜伏期为6~25ms,作用时程为50~150ms,上述结果提示,扣带皮层前部在皮层触压觉信息的整合中具有一定作用。  相似文献   

5.
大白鼠用水合氯醛腹腔注射作先导麻醉,然后用箭毒制动并施加人工呼吸。用玻璃微电极记录外侧隔核(nucleus septi lateralis,SL)神经元的单位活动及其对刺激视交叉上核(nucleus suprachiasmaticus,SCN)区的反应,用数据处理计算机作刺激前后单位放电的序列密度直方图。共观察了97个外侧隔核神经元,大多数单位的自发放电频率为1—15次/秒。在97个单位中,有82个(84.55%)对刺激视交叉上核区有反应。其中兴奋的有30个(36.6%),抑制的有51个(62.2%),反应不一致的1个(1.2%)。反应多数是短潜伏期的,但也观察到有长潜伏期的。在重复刺激作用下,外侧隔核神经元表现出反应减弱倾向。结果表明,刺激视交叉上核对外侧隔核神经元的电活动有明显影响,为该两核团间的纤维联系提供了电生理学证据。对两核团共同参与的各种生理机能作了简要的讨论。  相似文献   

6.
南方鲇头面部的皮肤受外界机械和化学物质刺激时采用电生理技术记录其面神经主要感觉支(上下颌须神经)的诱发放电。结果表明:由须的基部到顶端上下颌须神经对机械刺激的反应频率和幅度逐渐增强;上颌须神经相对下颌须神经有更高的味觉敏感性,其反应的幅度和频率更大,且阈值较低变化率大。两者都有脱敏和适应性现象;上下颌须神经含有3种类型单纤维,这3类单纤维及其联系的味蕾感受器可能构成3种基本的味觉单元。  相似文献   

7.
实验在26只用三碘季胺酚制动的成年家兔上进行。在中脑网状结构作细胞外记录,共获得128个具规则连续自发放电的非特异性感觉单位。电刺激杏仁基底核(AB)或内侧核(AME)能影响这些单位的自发放电以及大多数不同强度胫神经刺激所致的放电频率变化。对接受外周高阈值传入的单位,电刺激AB和AME的效应以抑制为主(54.3~65.5%)。对低阈值传入起反应的单位,AME刺激的效应仍以抑制为主(56.8%),而AB则以兴奋为主(50.0%)。提示杏仁调制网状结构内的感觉整合过程,并显示某种机能分化,这可以看作是情绪和感觉相互联系的一种机制。  相似文献   

8.
采用在体细胞外单细胞记录方法,研究调频声频率变化率及时程对调频声所诱发的听皮层神经元反应的影响.实验在34只乌拉坦麻醉的SD大鼠上进行,在皮层41区记录了113个对调频声有反应的细胞电活动.观察发现,调频声刺激的时程和频率变化率发生改变,可对诱发的听皮层神经元反应的反应型式和放电频数产生影响.这种影响表明,听皮层在复杂声上传信息的处理过程中可能存在复杂的编码机制.  相似文献   

9.
应用细胞内记录神经放电方法 ,研究Agrotissegetum雄蛾触角叶MGC神经元对性信息素的反应特征及时相编码特点。在此种雄蛾MGC中 ,投射神经元对性信息素的反应呈现一种双相反应模式。 2 6个MGC神经元均可对 1,3Hz频率的每个刺激有明显的双相反应 ,14个神经元可对 5Hz频率的每个刺激引起明显的双相反应 ,4个神经元仅能识别 7Hz频率的每个刺激 ,1个神经元可识别高至 10Hz频率的每个刺激。神经元对性信息素频率刺激的反应能力与神经元自发放电频率、反应时的超极化幅度等都有一定的相关关系  相似文献   

10.
研究证明了缰核(Hb)是刺激岛叶(INS)所引起的升压效应下行通路的主要中继站之一。电刺激INS引起升压反应,在刺激电极的同侧Hb内微量注射盐酸利多卡因,电刺激INS所引起的升压反应降低了36.9%。双侧Hb内微量注射盐酸利多卡因,电刺激INS所引起的升压反应降低了41.7%。单侧或双侧Hb内微量注射生理盐水或人工脑脊液均不能降低电刺激INS所引起的升压反应。在刺激INS前后用微电极记录Hb内心血管调节相关神经元放电活动的变化。电刺激INS后,Hb内心血管调节相关神经元的放电频率明显增加者占58%(21/36),频率明显减少者占14%(5/36),频率无明显变化者占28%(10/36)。结论表明:缰核是参与电刺激岛叶引起升压效应的主要下行通路之一。  相似文献   

11.
The lateral hypothalamic area (LHA) is one of the most important central areas in the regulation of feeding behavior[1]. The glycemia-sensitive neurons within the LHA sense the blood glucose level and subsequently trig-ger various visceral and somatic responses for maintaining the homeostasis of blood glucose concentration. Some electrophysiological studies have demonstrated that the gastric vagal afferent inputs could reach the LHA in the cat[2,3], but the studies did not reveal whether th…  相似文献   

12.
The glycemia-sensitive neuron in lateral hypothalamic area (LHA) is one of the important central neural events involved in the feeding control.Electrophysio-logical studies have demonstrated that gastrointestinal vagal afferent inputs could convey the meal-related infomation of gastrointestinal tract to the hypothalamus,In this study ,we examined whether the gastric vagal afferent inputs could reach the glycemia-sensitive neurons of the LHA by using in vivo extracelluar recording technique in the rat.The results showed that stimulation of gastric vagal nerves elictied two types of the LHA neurons responses:the phasic response (93/116,80.2%),and the change in cell‘s firing pattern (23/116,19.3%) ,Within the 93 cells that responded to the gastric vagal stimulation with a phasic response ,67(72.0%) showed an inhibition in the cell‘s firing rate 26(27.4%) were excited,Of the 23 cells that showed a change in the firing pattern 13 responded to the gastric vagal stimulation with a long-lasting increase or decrease in firing rate,the remaining 10 cells turned thier discrete spiking to the bust discharging .In addition ,of 101 LHA neurons including the ypes of responsive neurons,73(72.3%)were identified to be glycemia-sensitive neurons,These results demonstrated that the gastric vagal afferent inputs could reach the LHA and predominaltly reach those glycemia-seach neurons in the LHA ,Presumably,the modulation of glycemia-sensitive neurons of LHA by the gastric vagal afferent inputs may play an important role in the short-term regulation of feeding behavior.  相似文献   

13.
The basolateral amygdala (BLA) has a crucial role in emotional learning irrespective of valence. The BLA projection to the nucleus accumbens (NAc) is thought to modulate cue-triggered motivated behaviours, but our understanding of the interaction between these two brain regions has been limited by the inability to manipulate neural-circuit elements of this pathway selectively during behaviour. To circumvent this limitation, we used in vivo optogenetic stimulation or inhibition of glutamatergic fibres from the BLA to the NAc, coupled with intracranial pharmacology and ex vivo electrophysiology. Here we show that optical stimulation of the pathway from the BLA to the NAc in mice reinforces behavioural responding to earn additional optical stimulation of these synaptic inputs. Optical stimulation of these glutamatergic fibres required intra-NAc dopamine D1-type receptor signalling, but not D2-type receptor signalling. Brief optical inhibition of fibres from the BLA to the NAc reduced cue-evoked intake of sucrose, demonstrating an important role of this specific pathway in controlling naturally occurring reward-related behaviour. Moreover, although optical stimulation of glutamatergic fibres from the medial prefrontal cortex to the NAc also elicited reliable excitatory synaptic responses, optical self-stimulation behaviour was not observed by activation of this pathway. These data indicate that whereas the BLA is important for processing both positive and negative affect, the glutamatergic pathway from the BLA to the NAc, in conjunction with dopamine signalling in the NAc, promotes motivated behavioural responding. Thus, optogenetic manipulation of anatomically distinct synaptic inputs to the NAc reveals functionally distinct properties of these inputs in controlling reward-seeking behaviours.  相似文献   

14.
41只家兔在麻醉状态下胆流速度均匀,平均3.4毫升/公斤/时。对其中35只兔的膈下迷走神经施以电刺激,7只无反应,28只胆流有不同程度抑制。在这28只中,当膈下腹、背两侧迷走神经分别受到刺激时,都出现反应的有9只(32%);仅对刺激腹侧神经有反应的15只(53.6%);仅对刺激背侧神经有反应的4只(14.3%)。本工作揭示:支配家兔胆管活动的迷走神经并非仅仅是膈下腹侧支,而背侧支也有相当重要的作用。关于家兔胆汁分泌的研究曾有一些报道~[1.2.3];梅懋华等~[1]将家兔膈下双侧迷走神置于一个电极下,使两者同时受到刺激,绝大多数动物的胆汁流出速度发生变化.并证明这一效应的作用环节在于神经的兴奋引起胆管发生不同程度的收缩,阻碍了胆汁流出,而不是改变肝的分泌或胆囊活动.根据现有知识,家兔膈下腹侧迷走神经形成胃前神经丛,后者再发出纤维分布到肝~[4];至于膈下背侧迷走神经是否有纤维分布到肝和胆管,以及对胆汁流出是否产生影响,均未见报道,我们在实验中,注意到,若单独对家兔膈下腹侧或前侧迷走神经分别施以电刺激,各侧神经对胆汁排出能否产生影响,这在不同个体并不一致.于是导出了这样的问题;家兔膈下背侧迷走神经,是否也能借缩胆管机制影响胆汁的排出速度?如果能够,那么这两侧神经表现此种作用的场合各占多大比  相似文献   

15.
低频低强度电刺激家兔腓浅神经(SPN)能明显抑制电刺激主动脉神经(AN)诱发的心动过缓,对诱发的降压反应也表现轻度的抑制作用。静脉注射阿托品和两侧颈迷走神经切断后,可基本消除电刺激AN诱发的心率减慢,静脉注射心得安几乎不影响这种诱发的心率减慢,提示电刺激SPN对电刺激AN诱发的心率减慢的抑制作用与对心迷走神经系统的抑制有关。  相似文献   

16.
M B Calford  R Tweedale 《Nature》1988,332(6163):446-448
The somatosensory cortex of adult mammals has been shown to have a capacity to reorganize when inputs are removed by cutting afferent nerves or amputating a part of the body. The area of cortex that would normally respond to stimulation of the missing input can become responsive to inputs from other parts of the body surface. Although a few animals have been studied with repeat recording, no attempt has been made to follow the time-course of changes at cortical loci and the immediate effects of a small amputation have not been reported. We have followed the changes in response in the primary somatosensory cortex in the flying-fox following amputation of the single exposed digit on the forelimb. Immediately after amputation, neurons in the area of cortex receiving inputs from the missing digit were not silent but responded to stimulation of adjoining regions of the digit, hand, arm and wing. In the week following amputation, the enlarged receptive fields shrank until they covered only the skin around the amputation wound. The immediate response is interpreted as a removal of inhibition and the subsequent shrinking of the field may be due to re-establishment of the inhibitory balance in the affected cortex and its inputs.  相似文献   

17.
观察在Wistar大鼠给予利美尼定对基础和反射激活肾交感神经活动(renal sympathetic nerveactivity,RSNA)的影响.记录并分析对照组及实验组大鼠在基础状态以及在动物前肢神经给予0.8Hz和1.6Hz(15V,0.2ms)的电刺激时血压(blood pressure,BP)、心率(heart rate,HR)和肾神经活动的变化.结果表明实验组大鼠给利美尼定后可见不仅存在着与剂量相关的血压、心率和肾神经活动幅值的下降(P<0.05),而且功率谱分析结果显示电刺激同样改变了实验组大鼠肾神经活动能量的分布.肾神经活动的功率谱特征的改变虽然提示了利美尼定对肾交感神经活动可能具有某种程度的影响,但是它不通过体感系统影响肾交感神经活动的反射活性.  相似文献   

18.
桡神经前臂段浅层肌支的定位观察   总被引:3,自引:0,他引:3  
目的:为给前臂部创伤修复及肌瓣移植提供形态学依据。方法:采用解剖剥离测量方法,对25具(共50例)成人上肢标本的桡神经浅层肌支进行自身比例定位研究。结果:①桡神经发出的各肌支主要以2支型出现率最多;②桡神经发出的各肌支主要集中于上肢的Ⅵ段;③桡神经发出的各肌支进入各肌门的区位,均有倾向于以神经干为轴心近距离分布的规律。结论:确定了桡神经肌支的危险区段和危险区位,有利于开展带神经血管蒂肌瓣移植的肌支类型。  相似文献   

19.
Optimization of Multi-Criteria Experiments with Fuzzy Results   总被引:1,自引:0,他引:1  
杨帆  吴甦  Tilo  Pfeifer  Klaus  Hense 《清华大学学报》2006,11(6):686-692
Introduction To reach a best quality product, experiments and an op- timized design of experiments are required in an inte- grated quality management system. The best quality level of a manufacturing process or product is defined not only by one, but by m…  相似文献   

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