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应用微电极技术测定了45只大鼠325根单一听神经纤维的特征频率及其阈值和调谐曲线。测得特征频率的最低值为0.58kHz,最高值为62.6kHz。敏感度最高的频带在20~50kHz,敏感度最高的阈值为6dB(SPL),其相应的频率为27.49kHz。由最低阈值连线延续到边侧的调谐曲线,便形成了大鼠整个的听反应阈曲线。该听反应阈曲线与行为测听所观察到的听力曲线近似。  相似文献   

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Fernando  Nottebohm 《Ibis》1968,110(4):549-568
The present paper describes the results of experiments designed to evaluate the importance of auditory-motor experience in the development of song in the Chaffinch. For this purpose a number of Chaffinches collected as nestlings or adults were deafened by extirpating the cochlea at different ages. Recordings of their song made subsequently provide the material on which the paper is based. Since the results of the experiments can only be interpreted in the light of knowledge of normal song development, the latter is described from the observation of previous workers and from some new material. Of the 20 males deafened, only three came into full song of their own accord; song was induced in the rest by the administration of testosterone phenylacetate or testosterone propionate. Songs of abnormal length were common among first-year males though males deafened when two or more years old produced song of the normal length. The song of male Chaffinches deafened as adults, that is after they had produced full song for one or more breeding seasons, was infistinguishable from that produced by intact adult males. They even went through a “plastic” song stage in which some “intermediate” themes occurred. A first-year male deafened when it had almost stabilized its song produced song that gradually deviated more and more from normal song. This indicates that the bird had not yet laid down a long-term memory of its song independent of auditory feedback. First-year male Chaffinches deafened during early spring, mid-winter and late sumer, respectively, show that the more they were deprived of the normal period of auditory-motor experience, the simpler was the song they produced in their first spring. Thus, at the time of deafening they had acquired a particular auditory-motor experience, and it is the type of element established up to that time that is incorporated into full song. Male chaffinches brought into the laboratory as nestlings and deafened when three months old produced a virtually sfyctureless song, in which the only recognizable element was a sound reminiscent of the juvenile “chirrup”. The subsong and other calls of these birds were also highly abnormal. Song development in the Chaffinch clearly starts before song as such has made its appearance. The available evidence suggests that the kind of song a male Chaffinch produces depends directly on its auditory-motor experience before deafening. There is no indication that deafening achieves its effects on the resultant song by interfering with the hormonal substrate. Relatively stable song end patterns develop in the absence of auditory feedback, so their occurrence does not necessitate the postulation of templates or preconceived patterns. Song development differs markedly from species to species.  相似文献   

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Thyroxin injection with associated increases in metabolic rate does not significantly affect simple reaction time to an electric shock. Hypophysectomy and thyroidectomy with associated decreases in metabolic rate produce a slight decline in reaction speed. Reaction time is long in young animals, probably due to incomplete development of certain integrative and conductive systems; it remains virtually constant between puberty and relatively advanced age when it increases rapidly, probably due to physicochemical changes in the composition of the conducting nervous system.  相似文献   

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Dynamic sweetness perception of commercial food grade trehalose, sucrose solutions and their mixtures were studied for a wide range of concentrations. For gustatory reaction time (GRT), concentrations ranged from 2.3 to 13.8% for sucrose and up to 23.0% for trehalose. For time intensity (T-I) sucrose or trehalose solutions (concentration range 2.3–36.8%) and their combinations (23.0 and 36.8% total solids) were analyzed. Trehalose had bigger GRT along the studied range. Both sugars presented similar values for persistence and times of plateau and to maximum intensity, while a significant difference was observed in intensity and GRT at equal concentrations. Trehalose had longer persistence than sucrose in equi -sweet solutions. Overall sweetness profile of some sucrose solutions (i.e., 29.9% sucrose solution and 0.6 sucrose/trehalose ratio mixture at 36.8% total solids) were perceived as similar to mixtures of sucrose/trehalose or single trehalose solutions, which suggests the possibility of sugar replacement without completely modifying sweetness perception.

PRACTICAL APPLICATIONS


It has been suggested that trehalose may be a potential substitute for sucrose and other sugars used in food formulation because, although its chemical structure is very similar to that of sucrose, it is more stable at low pH and high temperatures. It is not involved in caramelization and does not participate in Maillard reaction with amino acids/proteins. In order to fully establish the potential of trehalose as a functional replacement of sucrose we have determined the sweetness dynamic profile (gustatory reaction time and time-intensity curves) of trehalose solutions and sucrose/trehalose solutions; this aspect is needed for adequately replacing (partially or totally) sucrose in food systems.  相似文献   

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建立了蛙下丘听觉神经元对双耳刺激强度差检测功能的一个数学模型。按此模型所作的计算机仿真和相应实验结果比较的一致性支持了下列假设 :下丘中的EO神经元对同侧刺激不产生反应可能是由于接受了来自同侧的强烈抑制性输入 ,从而掩盖了它同时接受到的来自同侧耳的兴奋性输入。而来自同侧的抑制性输入 ,与来自对侧的兴奋性输入可能通过突触前抑制的相互作用 ,则导致了EE神经元的双耳抑制现象。  相似文献   

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黑长臂猿(Hylobates concolor)鸣叫行为研究   总被引:7,自引:0,他引:7  
本文基于对云南黑长臂猿多年的野外研究,报道其鸣叫行为的一些特性。黑长臂猿通常在上午鸣叫,且大多数发生在930分以前,鸣叫的起始时间具季节性变化,有两个较为集中的时间,一个在730分左右,另一个在830分左右,然而起始时间并不与日出时间一致。黑长臂猿平均每两天鸣叫一次,日鸣叫发生频次在50%左右,鸣叫的发生也随着季节而变化。鸣叫的持续时间无群体的差异,一次鸣叫的平均时间在12分钟左右(除了GG群),但群体在不同季节鸣叫时间长短不一。本文的研究结果同时还表明一个群体的鸣叫并未引起邻近其它群体的鸣叫。  相似文献   

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"Black—short ears—kinky tail—rodless" mice, controlled by "pink eyed—dilute—brown" mice, were tested on an inclined plane in order to determine if they are photically sensitive, and, if so, to get a quantitative expression for their visual receptivity. Rodless and control animals were tested in the dark to obtain an expression for normal geotropic orientation. Light was then introduced to modify these reactions if possible. Under light, the controls failed to orient, whereas the rodless gave reactions almost identical with those in the dark. This test has failed in this experiment to suggest sight in the rodless mouse.  相似文献   

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兔杏仁体向皮层听区的直接投射及其比较生理学意义   总被引:2,自引:2,他引:2  
刺激杏仁外侧核或基底核,可在兔听区皮层观察到诱发电位,诱发电位分布在WoolseyAI、AⅡ区及溴鼻沟后缘听区皮层(ACBRS区),以ACBRS区反应为最大。诱发反应的潜伏期最短为2毫秒,表明杏仁向听皮层的投射可能是单突触的。形态学工作揭示,兔主要听区ACBRS区电泳辣根过氧化物酶(HRP),杏仁外侧核及基底核都观察到逆行标记细胞,标记细胞数量以杏仁外侧核为多;WoolseyAⅠ、AⅡ区电泳HRP  相似文献   

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We investigated whether the perception of the crispness and staleness of potato chips can be affected by modifying the sounds produced during the biting action. Participants in our study bit into potato chips with their front teeth while rating either their crispness or freshness using a computer‐based visual analog scale. The results demonstrate that the perception of both the crispness and staleness was systematically altered by varying the loudness and/or frequency composition of the auditory feedback elicited during the biting action. The potato chips were perceived as being both crisper and fresher when either the overall sound level was increased, or when just the high frequency sounds (in the range of 2 kHz?20 kHz) were selectively amplified. These results highlight the significant role that auditory cues can play in modulating the perception and evaluation of foodstuffs (despite the fact that consumers are often unaware of the influence of such auditory cues). The paradigm reported here also provides a novel empiric methodology for assessing such multisensory contributions to food perception.  相似文献   

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用免疫组织化学方法研究P物质在雌雄黄雀发声控制核团和听觉中枢内的分布,结合计算机图像分析仪检测SP免疫阳性细胞和末梢的灰度值,并作雌雄比较。结果如下:1.在发声学习中枢嗅叶X区有大量的SP阳性神经末梢和一些神经细胞。2.在发声控制核团前脑高级发声中枢(HVc)、古纹状体栎核、发声学习中枢新纹状体巨细胞核和丘脑背内侧核外侧部内有许多的SP免疫阳性细胞。3.在发声控制中枢中脑背内侧核和延髓舌下神经核气管呜管部、听觉中枢丘脑卵圆核的壳区、中脑背外侧核壳区及中脑丘间核等有密集的SP免疫阳性神经末梢和纤维分布;雄性发声中枢内SP的分布比雌性丰富,两者有显著的差异。结果表明:SP的分布在雌雄发声中枢之间存在显著的性双态;SP广泛分布于黄雀发声控制核团和部分听觉中枢内,提示SP可能在发声控制及听觉中枢内具有重要的生理功能。  相似文献   

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Three-week-old male rats of the Wistar strain were given tritiated thymidine, 1 µc/gm body weight, intraperitoneally and were killed at intervals from 0.25 to 72 hours later. Autoradiographs were made from 5 µ sections, stained by the Feulgen method. The replication time and its component intervals were determined from the scoring of the labeling of interphase nuclei as well as of prophase, metaphase, anaphase, and telophase nuclei. Absorption of the intraperitoneally injected label is rapid and is attended by "flash" labeling during interphase. The results show that at any one time about 4 per cent of the liver cells are synthesizing DNA preliminary to cell division. These cells alternate with waves of other cells and it is estimated that about 10 per cent of the liver cell population is engaged in cell duplication. The replication time is about 21.5 hours, and its component intervals occupy the following times: DNA synthesis, 9 hours; post-DNA synthesis gap, 0.50 hour; prophase, 1.3 hours; metaphase, 1.0 hour; anaphase, 0.4 hour; telophase, 0.3 hour; postmitosis gap, 9.0 hours. A group of liver cells has been recorded in at least 3 successive replication cycles.  相似文献   

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