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1.
本研究结果表明,驴下橄榄复合体由主核、两个副核和三个细胞柱组成,平均长度14.4mm。主核呈囊状,囊壁皱襞少而小,囊底不弯曲;内侧副核有6个多变的组成部,以“八”字形B核为特殊;背侧副核结构松散;三个细胞柱未见报道,暂名:下橄榄背板背侧细胞柱、下橄榄腹内侧细胞柱和下橄榄底细胞柱。主核和两个副核主要成自中等卵圆形细胞,它们占细胞总数的89.8%,其余为小细胞。三个特殊细胞柱除含中、小细胞外,还有13.1~58.5%的大细胞。  相似文献   

2.
Experimentally induced visual projections into auditory thalamus and cortex   总被引:13,自引:0,他引:13  
Retinal cells have been induced to project into the medial geniculate nucleus, the principal auditory thalamic nucleus, in newborn ferrets by reduction of targets of retinal axons in one hemisphere and creation of alternative terminal space for these fibers in the auditory thalamus. Many cells in the medial geniculate nucleus are then visually driven, have large receptive fields, and receive input from retinal ganglion cells with small somata and slow conduction velocities. Visual cells with long conduction latencies and large contralateral receptive fields can also be recorded in primary auditory cortex. Some visual cells in auditory cortex are direction selective or have oriented receptive fields that resemble those of complex cells in primary visual cortex. Thus, functional visual projections can be routed into nonvisual structures in higher mammals, suggesting that the modality of a sensory thalamic nucleus or cortical area may be specified by its inputs during development.  相似文献   

3.
A neural map of auditory space in the owl   总被引:11,自引:0,他引:11  
Auditory units that responded to sound only when it originated from a limited area of space were found in the lateral and anterior portions of the midbrain auditory nucleus of the owl (Tyto alba). The areas of space to which these units responded (their receptive fields) were largely independent of the nature and intensity of the sound stimulus. The units were arranged systematically within the midbrain auditory nucleus according to the relative locations of their receptive fields, thus creating a physiological map of auditory space.  相似文献   

4.
A map of visual space induced in primary auditory cortex   总被引:7,自引:0,他引:7  
Maps of sensory surfaces are a fundamental feature of sensory cortical areas of the brain. The relative roles of afferents and targets in forming neocortical maps in higher mammals can be examined in ferrets in which retinal inputs are directed into the auditory pathway. In these animals, the primary auditory cortex contains a systematic representation of the retina (and of visual space) rather than a representation of the cochlea (and of sound frequency). A representation of a two-dimensional sensory epithelium, the retina, in cortex that normally represents a one-dimensional epithelium, the cochlea, suggests that the same cortical area can support different types of maps. Topography in the visual map arises both from thalamocortical projections that are characteristic of the auditory pathway and from patterns of retinal activity that provide the input to the map.  相似文献   

5.
Neurons in the lateral belt areas of rhesus monkey auditory cortex prefer complex sounds to pure tones, but functional specializations of these multiple maps in the superior temporal region have not been determined. We tested the specificity of neurons in the lateral belt with species-specific communication calls presented at different azimuth positions. We found that neurons in the anterior belt are more selective for the type of call, whereas neurons in the caudal belt consistently show the greatest spatial selectivity. These results suggest that cortical processing of auditory spatial and pattern information is performed in specialized streams rather than one homogeneously distributed system.  相似文献   

6.
猪下丘脑开胃素 A的分布定位   总被引:7,自引:2,他引:5  
用免疫组织化学方法研究了5头苏钟猪下丘脑内开胃素(orexin)A的分布。结果表明,在猪下丘脑内,开胃素A免疫阳性神经元分布于下丘脑的视前内侧区、室周核、室旁核、视上核、背内侧核、穹隆周核、乳头体核、前区、外侧区和后区等部位,以下丘脑外侧区、乳头体核和视上核出现的免疫阳性神经元最多,以室周核的最少。这一结果与在其他动物上获得的基本相似。  相似文献   

7.
用辣根过氧化物酶法研究了4只仔猪大脑皮质十字前回和后回传入神经的来源,将HRP注入十字前回,在蓝斑,中缝背核,中脑中央灰质,丘脑背内侧核,腹前核,腹外侧核和板内核,十字前回和薛氏回等诸多结构内出现标记细胞。将HRP注入十字后回,在蓝斑,中脑中央灰质,中缝背核,丘脑外侧核群,背内侧核,板内核,十字前回和后回,冠状回和扣带回等处出现标记细胞,结果表明,此二回均接受广泛的传入纤维,在丘脑皮质联系中,十字  相似文献   

8.
猪的下橄榄核簇由内侧副核、背侧副核和主核组成。内侧副核分为腹侧部、背侧部、Kooy氏背帽、Koo氏腹外侧突、B核和背内侧细胞柱;背侧副核分为主部和后脚;主核分为背板和腹板。在内侧副核腹侧部的腹侧,锥体的背侧,有一从未被报道过的特殊核团,暂命名为底核。  相似文献   

9.
采用免疫组织化学法研究了10只青紫蓝兔脑内开胃素(Orexin) A免疫阳性神经元和神经纤维的分布。结果显示,Orexin A免疫阳性神经元分布于下丘脑的视上核、室旁核、背内侧核、穹隆周核、外侧区、前区和后区以及底丘脑的未定带。Orexin A免疫阳性神经纤维广泛分布于中枢神经系统内,在端脑分布于大脑皮质、尾状核、隔核和杏仁核;在间脑分布于丘脑、下丘脑、上丘脑和垂体;在中脑分布于中央灰质、前丘、后丘、黑质、网状结构和中缝核;在脑桥分布于蓝斑、网状结构和中缝核;在延髓分布于极后区、孤束核和迷走神经背侧运动核;在小脑和脊髓也有分布。  相似文献   

10.
利用10只北京鸭脑制成连续切片,经Nissl法染色,光镜观察分布于中脑内D-K核、Cajal氏中介核、脚间核、三叉神经中脑核、环核及中继核群的形态及细胞构筑。结果表明:1,环核位圩内侧纵束的内侧;2、结合臂交叉核位于中央上核的前方;3.中脑线形核与尾侧线形核相连;4.D-K核、Cajal氏中介核、脚间核、三叉神经中脑核与其它禽类的同名结构相近似。  相似文献   

11.
The central auditory system translates sound localization cues into a map of space guided, in part, by visual experience. In barn owls, this process takes place in the external nucleus of the inferior colliculus (ICX). However, to date, no trace of visual activity has been observed in this auditory nucleus. Here we show that strong visual responses, which are appropriate to guide auditory plasticity, appear in the ICX when inhibition is blocked in the optic tectum. Thus, visual spatial information is gated into the auditory system by an inhibitory mechanism that operates at a higher level in the brain.  相似文献   

12.
Monkeys that were trained to perform auditory and visual short-term memory tasks (delayed matching-to-sample) received lesions of the auditory association cortex in the superior temporal gyrus. Although visual memory was completely unaffected by the lesions, auditory memory was severely impaired. Despite this impairment, all monkeys could discriminate sounds closer in frequency than those used in the auditory memory task. This result suggests that the superior temporal cortex plays a role in auditory processing and retention similar to the role the inferior temporal cortex plays in visual processing and retention.  相似文献   

13.
Temporal selectivity in the central auditory system of the leopard frog   总被引:3,自引:0,他引:3  
Amplitude modulation is a predominant temporal feature in many vocal signals. The leopard frog, Rana pipiens, has a class of neurons in the central auditory system that respond selectively to particular rates of amplitude modulation; these neurons can be characterized by a temporal tuning curve. Such selectivity is absent in the peripheral auditory system. This type of transformation may be fundamental in processing temporal information in the vertebrate sensory nervous system.  相似文献   

14.
Sound clicks or light flashes modify somatic sensory activity in the cuneate nucleus of the cat. The techniques of gross potential recording in the cuneate nucleus or medial lemniscal tract, of single unit recording in the cuneate nucleus, and of excitability testing of cuneate terminals demonstrate this heterosensory interactionsensory interaction.  相似文献   

15.
Vision guides the adjustment of auditory localization in young barn owls   总被引:4,自引:0,他引:4  
Barn owls raised with one ear plugged make systematic errors in auditory localization when the earplug is removed. Young owls correct their localization errors within a few weeks. However, such animals did not correct their auditory localization errors when deprived of vision. Moreover, when prisms were mounted in front of their eyes, they adjusted their auditory localization to match the visual error induced by the prisms, as long as the visual and auditory errors were within the same quadrant of directions. The results demonstrate that, during development, the visual system provides the spatial reference for fine-tuning auditory localization.  相似文献   

16.
Sulitable electrical stimulaltion of the region of the decussation of the olivocochlear bundles, which supply efferent innervation to the organ of Corti, was found to abolish the response of the auditory cortex to a click, without changing the responses (N(1) and N(2)) of the eighth nerve in cats. At higher stimulation values the eighth nerve responses also were abolished, and at intermediate stimulus values responses at the medial geniculate and inferior colliculus were suppressed.  相似文献   

17.
Cerebral auditory areas were delineated in the awake, passively listening, rhesus monkey by comparing the rates of glucose utilization in an intact hemisphere and in an acoustically isolated contralateral hemisphere of the same animal. The auditory system defined in this way occupied large portions of cerebral tissue, an extent probably second only to that of the visual system. Cortically, the activated areas included the entire superior temporal gyrus and large portions of the parietal, prefrontal, and limbic lobes. Several auditory areas overlapped with previously identified visual areas, suggesting that the auditory system, like the visual system, contains separate pathways for processing stimulus quality, location, and motion.  相似文献   

18.
Injection of norepinephrine in the lateral ventricles of rats recovering from lateral hypothalamic anorexia caused immediate feeding and, frequently, overeating. Intraventricular administration of the alpha-noradrenergic blocker, phentolamine, suppressed feeding in both normal rats and rats that had recovered from lateral hypothalamic lesions. Feeding is reinforced by ascending medial forebrain bundle fibers that form alpha-noradrenergic synapses in the hypothalamus and forebrain. Damage to these fibers suppresses feeding by reducing noradrenergic transmission and, hence, the rewarding value of food. Recovery of feeding after hypothalamic lesions coincides with the recovery of noradrenergic reward function.  相似文献   

19.
齐口裂腹鱼端脑形态和组织学研究   总被引:3,自引:0,他引:3  
采用苏木精 -伊红、美兰染色技术对 5尾齐口裂腹鱼端脑的外部形态和组织结构进行了研究。观察发现 ,齐口裂腹鱼的端脑发达 ,由嗅球、嗅茎和左右端脑半球构成。嗅球位于嗅窝内 ,嗅囊的后方 ,以嗅茎与后面的左右端脑半球联系。嗅球的组织结构成层状结构 ,从外向内依次为上皮、神经纤维层和小细胞层。端脑半球外部被有原脑皮 ,两者之间的腔隙为脑室 ,其内的纹状体被横行和纵行的沟分成若干小叶。神经核分布于纹状体的周缘 ,主要有连前核、背嗅核、侧嗅核、视前核、梨状核、侧连核和脚内核等。本文对纹状体内各核的特征进行观察和描述。  相似文献   

20.
用Nissl氏法、Weil氏法和Golgi—Cox氏法染色的猪脑干额状面,矢状面和水平面连续切片研究了猪中脑中央灰质(CG)的形态和构筑。猪CG根据细胞的形态、大小、密度及神经纤维的走向可分为四部和一个核:①内侧部,包围中脑水管,②背侧部,位于内侧部的背侧;③腹侧部,位于内侧部的腹侧;④外侧部,在背侧部和腹侧部之间,位于内侧部的外侧;⑤背外侧缘核,呈楔形嵌于外侧部的背外侧缘。  相似文献   

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