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1.
胚胎期光照和皮质酮处理对日龄小鸡记忆的作用   总被引:1,自引:0,他引:1  
该实验对胚胎发育后期的鸡胚进行光孵化,暗孵化以及药物注射处理后,采用一次性味觉被动回避行为模式观察它们对出生后小鸡记忆保持的影响并对其作用机制进行了初步探讨,结果表明胚胎期光照可增强小鸡记忆的保持,使用糖皮质激素受体拮抗剂可阻断光照对小鸡记忆的增强作用,对暗孵化鸡胚注射皮质酮可以促进出生后小鸡记忆的保持,因此皮质酮可能能与光照对小鸡记忆的增强过程,蛋白合成抑制剂在一定程度上阻断皮质醇对小鸡记忆的增  相似文献   

2.
迷走神经刺激对记忆的影响   总被引:1,自引:0,他引:1  
迷走神经刺激(vagus nerve stimulation, VNS)用于终止癫痫发作已经有二十年的历史.期间VNS也用于难治性抑郁的治疗.在治疗过程中研究者发现VNS 对癫痫、抑郁患者的学习和记忆能力有改善作用,这种改善作用在一些动物和人体实验中也得到证实.但VNS在记忆形成的哪个阶段起作用以及如何起作用的具体机制尚不十分清楚.因此,进一步了解VNS对记忆的影响及作用机制有利于探讨记忆形成的生理机制,也为临床治疗特异性记忆障碍和相关神经精神疾病提供新的思路和有益补充.本文综述了近十几年来VNS对记忆的影响及相关机制.  相似文献   

3.
应用双向凝胶电泳结合质谱鉴定和数据库检索,分析比较C57BL/6J小鼠在多T迷宫(MTM)训练和记忆测试组与未训练组海马蛋白表达的差异,探讨与MTM空间记忆相关的蛋白质.C57BL/6J小鼠经MTM训练后,可对相应的空间线索保持记忆能力,其海马蛋白质表达存在明显差异,14个蛋白质与MTM空间记忆形成显著相关.其中,6个蛋白点表达显著上调,8个蛋白点表达水平显著降低.这些蛋白按功能可分为6类: 细胞骨架相关蛋白,物质运输相关蛋白,蛋白合成相关蛋白,能量和物质代谢相关蛋白,信号转导相关蛋白,通道蛋白. 这些空间记忆形成相关蛋白的研究深化了对空间记忆机制的认识,为研究和治疗认知相关疾病提供了新靶标.  相似文献   

4.
学习记忆的形成依赖于转录机制.近年研究发现,染色质修饰在基因表达调节中起重要作用.组蛋白乙酰化和去乙酰化是染色质修饰中最为常见调节方式,参与基因的转录调控.乙酰化可以激活转录,促进记忆的形成.组蛋白去乙酰化酶抑制剂可以增强突触可塑性,改善记忆损伤.因此,对于染色质修饰的深入研究,不仅有助于阐明记忆形成的分子机制,而且对记忆相关疾病的治疗以及新药物研发也具有重要指导意义.本文主要就组蛋白乙酰转移酶调节基因转录以及组蛋白去乙酰化酶抑制剂促进记忆形成的作用机理进行综述.  相似文献   

5.
日龄雏鸡的一次性被动回避学习任务模型被广泛应用于记忆机制研究, 具
有多方面的优势和便利性. apamin 是SK 通道(钙离子激活的小电导钾离子通道)的一
种选择性阻断剂, 以往研究显示其可能增进记忆. 但人们对其作用机制的了解不是很
充分. 使用颅内微量注射方法, 在雏鸡中枢记忆相关核团IMM 施加apamin, 研究其
对记忆形成和保持的影响. 实验结果显示, 雏鸡在弱刺激条件下的被动回避任务中本
不能形成稳定的长时记忆, 但在训练前短时间内或训练后立即注射适量apamin, 可
以易化长时记忆的形成. 然而, apamin 对记忆随时间衰退的过程几乎没有影响, 即对
记忆保持没有增进作用. 此外, 在左、右脑IMM 单侧注射apamin 都可促进记忆形成,
但所需剂量高于双侧注射时, 且在左侧产生效应的时间早于右侧, 这体现了两侧
IMM 在记忆加工中作用的不对称性. 这些结果提示, apamin 可能通过阻断中枢记忆
相关核团内的SK 通道, 影响由训练诱发的、与记忆形成有关的某些分子或细胞事件,
在一定程度上起到改善记忆的作用.  相似文献   

6.
恐惧位于记忆和情感的交汇处,既是触发防御机制以适应危险的一种情绪反应,又是研究记忆的模型。恐惧调节障碍时常会导致焦虑。该文综述了条件恐惧记忆形成及维持的主要机制,总结了在恐惧记忆产生后,神经元响应钙离子内流时相关的分子生物学变化,如CaMKs、PKA、PKM-ζ、Rho GTPases等激酶的激活,以及下游MAPK信号的转导、转录因子的调控、相关基因的表达等方面的现有研究结果,试图理清恐惧记忆相关分子机制。鉴于恐惧调节与诸如创伤后应激障碍(PTSD)之类的某些情绪障碍有密切关系,条件恐惧记忆形成的分子机制研究可能为精神障碍药物的开发提供潜在的靶标。  相似文献   

7.
胃泌素释放肽(gastrin-releasing peptide,GRP)是蛙皮素(bombesin,BB/BN)在哺乳动物中的同系物,在中枢神经系统中广泛分布,是一种重要的脑内神经调质,参与动物的多种生理功能和本能行为,在大脑的高级功能方面也发挥一定的作用.在神经系统中,随着GRP水平的改变,动物的记忆特别是与恐惧、焦虑相关记忆的形成、巩固和消退以及突触可塑性均发生不同程度的变化.GRP及其受体还被认为与神经系统性疾病有关,是潜在的神经系统性疾病的治疗靶点,但其相关的机制尚未明确.很多研究者基于不同实验方法提出了相关假设.本文从传统药理学、遗传学和电生理学方面对GRP系统在厌恶性情绪驱动的记忆、突触可塑性变化以及在中枢神经系统中的作用机制进行综述,希望为进一步明确GRP系统在中枢神经系统中的作用研究提供新的思路.  相似文献   

8.
恐惧消散被认为是一种通过形成新的抑制性学习来拮抗最初的恐惧记忆的复杂过程。目前,通过旨在促进恐惧消散的疗法治疗诸如焦虑症等神经精神疾病已在临床上取得了较好的疗效,因此,如何更有效持久地维持恐惧消散记忆具有重要的意义。围绕与恐惧记忆消散相关的脑区及恐惧记忆消散的分子机制进行阐述,有助于更深入地理解恐惧记忆消散相关的神经生物学机制,为后续研究提供新的方向。  相似文献   

9.
恐惧作为个体应对内外界危险因素形成的自我保护机制的一部分,在生物体的生存中发挥着重要作用.但过度的恐惧不仅对个体生存无益,反而易引发创伤后应激障碍、焦虑等精神疾病,严重影响个体生活质量.临床上通常采用基于行为学研究结果的暴露疗法对恐惧相关疾病进行治疗,然而在患者处于治疗环境之外的时候,上述症状经常会复发.因此,解析恐惧记忆相关神经环路内信息处理的神经机制,对于理解这些疾病的发生发展,寻求切实有效的治疗方案至关重要.大量研究表明与恐惧记忆消退相关的脑区主要涉及杏仁核、内侧前额叶和海马.在恐惧消退的过程中,这3个脑区表现出特定的神经振荡模式,而且这些活动也具有同步性,构成了恐惧记忆成功消退的神经基础.未来可利用基于神经神经振荡的无创性脑刺激手段干预恐惧记忆消退的神经环路,以促进恐惧记忆的消退并避免复发,为恐惧相关障碍的临床治疗提供重要的科学依据.  相似文献   

10.
β淀粉样蛋白(Aβ)沉积形成斑块是阿尔茨海默病(AD)的病理标志之一. 以β淀粉样前体蛋白(AβPP)为基础的转基因小鼠模型表现出斑块形成加速和记忆损伤. 然而,在一些模型中,记忆丧失与斑块形成的相关性较差. 我们实验室最近报道了AD患者和动物模型的认知障碍与其体内甲醛水平有很强的相关性. 本研究发现,AβPPLon/Swe转基因小鼠3月龄时表现出记忆缺陷,而在6月龄时记忆正常,其工作记忆与甲醛水平变化相反. 与对照组相比,3月龄小鼠记忆受损伴随着甲醛水平的增高和过度磷酸化tau的增加. 腹腔注射甲醛清除剂白藜芦醇可通过降低甲醛水平和tau蛋白的过度磷酸化,挽回小鼠的记忆损伤. 6月龄AβPPLon/Swe小鼠甲醛水平和工作记忆与对照组相似,伴随甲醛降解酶ALDH2和ADH3表达增加. 结果显示,在AβPPLon/Swe转基因小鼠中,大脑甲醛水平与记忆变化进程显著相关,且记忆的恢复与甲醛水平下降相关. 该研究为揭示阿尔茨海默病机制研究提供了新视角.  相似文献   

11.
记忆T细胞平行分化模型的理论研究   总被引:4,自引:0,他引:4  
为了从理论上讨论T细胞记忆维持机制的问题,基于T细胞的平行分化假说建立了非线性理论模型,利用此模型,在不同的抗原初值下得到了三种不同类型的应答。用优化剂量的抗原免疫生物体并且抗原存在时记忆能持续很长的时间,而失去抗原的同时将失去记忆,得出记忆T细胞平行分化模型确有记忆机制;并发现记忆强度与剩余抗原量有直接的关系,还进一步讨论了记忆细胞寿命的问题,并对体外情况作了预言。  相似文献   

12.
Data available in literature on immunomorphological aspects of the immunological memory formation are summarized. Features of B memory cells and mechanisms of their activation are analyzed. Relations between antigen localization in the lymphoid follicles, the formation of virgin centres there and induction of B memory cells and organs of the immune system in the immunological memory are discussed.  相似文献   

13.
Autobiographical memory refers to events and information about personal life and the self. Within autobiographical memory, many authors make a difference between episodic and semantic components. Study of retrograde amnesia gives information about memory consolidation. According to the "standard model" of consolidation, the medial temporal lobe plays a time-limited role in retrieval memory. Functional neuroanatomy studies of autobiographical memory are very few and many are recent. These studies concern which brain regions are involved in the autobiographical retrieval, episodic or semantic autobiographical memory and consolidation process. Results show that autobiographical retrieval depends on specific brain regions like frontal cortex. Concerning memory consolidation, findings are most consistent with the idea that hippocampal complex is involved in both recent and remote memories.  相似文献   

14.
Cognitive neuroscience approaches to memory attempt to elucidate the brain processes and systems that are involved in different forms of memory and learning. This paper examines recent research from brain-damaged patients and neuroimaging studies that bears on the distinction between explicit and implicit forms of memory. Explicit memory refers to conscious recollection of previous experiences, whereas implicit memory refers to the non-conscious effects of past experiences on subsequent performance and behaviour. Converging evidence suggests that an implicit form of memory known as priming is associated with changes in posterior cortical regions that are involved in perceptual processing; some of the same regions may contribute to explicit memory. The hippocampal formation and prefrontal cortex also play important roles in explicit memory. Evidence is presented from recent PET scanning studies that suggests that frontal regions are associated with intentional strategic efforts to retrieve recent experiences, whereas the hippocampal formation is associated with some aspect of the actual recollection of an event.  相似文献   

15.
Larsson  Maria 《Chemical senses》1997,22(6):623-633
Information on long-term memory for common odors is discussed.Olfactory parameters (i. e. familiarity, recognition, identification)and their relationship to current memory theory are highlighted.Emphasis is focused on the impact of semantic memory on episodicodor recognition. In contrast to previous research suggestingthat verbal/semantic factors play a negligible role in olfactorymemory, the present review indicates that episodic odor informationis mediated by factors that can be subsumed under the rubricof semantic memory. Specific odor knowledge, such as perceivedfamiliarity and identifiability, is strongly and positivelyrelated to episodic odor memory performance. Age-related impairmentsin various olfactory and cognitive parameters and the potentialdetrimental effects in episodic odor memory are discussed. Finally,the issue of whether olfactory memory should be conceptualizedas an independent process, or whether it shares characteristicswith memory for verbal and visual information, is addressed.Chem. Senses 22: 623–633, 1997.  相似文献   

16.
Phenomenologically inspired by dolphins’ unihemispheric sleep, we introduce a minimal model for random walks with physiological memory. The physiological memory consists of long-term memory which includes unconscious implicit memory and conscious explicit memory, and working memory which serves as a multi-component system for integrating, manipulating and managing short-term storage. The model assumes that the sleeping state allows retrievals of episodic objects merely from the episodic buffer where these memory objects are invoked corresponding to the ambient objects and are thus object-oriented, together with intermittent but increasing use of implicit memory in which decisions are unconsciously picked up from historical time series. The process of memory decay and forgetting is constructed in the episodic buffer. The walker’s risk attitude, as a product of physiological heuristics according to the performance of objected-oriented decisions, is imposed on implicit memory. The analytical results of unihemispheric random walks with the mixture of object-oriented and time-oriented memory, as well as the long-time behavior which tends to the use of implicit memory, are provided, indicating the common sense that a conservative risk attitude is inclinable to slow movement.  相似文献   

17.
昆虫记忆的形成机制及生态适应性   总被引:1,自引:0,他引:1  
介绍近十几年来利用蜜蜂Apis mellifera L.、果蝇Drosophila melanogaster Meigen和寄生蜂等昆虫对学习和记忆行为研究的成果。这些研究表明昆虫的记忆形成是多阶段的。从短时记忆向长时记忆的形成过程中,cAMP反应元件结合蛋白(cAMP response element-bindingprotein,CREB)起重要的作用;而蘑菇体是学习、记忆形成的主要位点。已有的研究还表明昆虫记忆的动态是适应于不同物种的生态学需要。这些研究为探索昆虫和其它动物记忆的形成和生态适应性提供了理论基础。  相似文献   

18.
Introspectively we experience a phenomenally rich world. In stark contrast, many studies show that we can only report on the few items that we happen to attend to. So what happens to the unattended objects? Are these consciously processed as our first person perspective would have us believe, or are they – in fact – entirely unconscious? Here, we attempt to resolve this question by investigating the perceptual characteristics of visual sensory memory. Sensory memory is a fleeting, high-capacity form of memory that precedes attentional selection and working memory. We found that memory capacity benefits from figural information induced by the Kanizsa illusion. Importantly, this benefit was larger for sensory memory than for working memory and depended critically on the illusion, not on the stimulus configuration. This shows that pre-attentive sensory memory contains representations that have a genuinely perceptual nature, suggesting that non-attended representations are phenomenally experienced rather than unconscious.  相似文献   

19.
An approach to episodic associative memory is presented, which has several desirable properties as a human memory model. The design is based on topological feature map representation of data. An ordinary feature map is a classifier, mapping an input vector onto a topologically meaningful location on the map. A trace feature map, in addition, creates a memory trace on that location. The traces can be stored episodically in a single presentation, and retrieved with a partial cue. Nearby traces overlap, which results in plausible memory interference behavior. Performance degrades gracefully as the memory is overloaded. More recent traces are easier to recall as are traces that are unique in the memory.This research was supported in part by an ITA Foundation grant and by fellowships from the Academy of Finland, the Emil Aaltonen Foundation and the Foundation for the Advancement of Technology (Finland) when the author was at UCLA  相似文献   

20.
Psychophysical and neurophysiological studies have suggested that memory is not simply a carbon copy of our experience: Memories are modified or new memories are formed depending on the dynamic structure of our experience, and specifically, on how gradually or abruptly the world changes. We present a statistical theory of memory formation in a dynamic environment, based on a nonparametric generalization of the switching Kalman filter. We show that this theory can qualitatively account for several psychophysical and neural phenomena, and present results of a new visual memory experiment aimed at testing the theory directly. Our experimental findings suggest that humans can use temporal discontinuities in the structure of the environment to determine when to form new memory traces. The statistical perspective we offer provides a coherent account of the conditions under which new experience is integrated into an old memory versus forming a new memory, and shows that memory formation depends on inferences about the underlying structure of our experience.  相似文献   

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