Recovery of learning and memory is associated with chromatin remodelling

Neurodegenerative diseases of the central nervous system are often associated with impaired learning and memory, eventually leading to dementia. An important aspect in pre-clinical research is the exploration of strategies to re-establish learning ability and access to long-term memories. By using a mouse model that allows temporally and spatially restricted induction of neuronal loss, we show here that environmental enrichment reinstated learning behaviour and re-established access to long-term memories after significant brain atrophy and neuronal loss had already occurred. Environmental enrichment correlated with chromatin modifications (increased histone-tail acetylation). Moreover, increased histone acetylation by inhibitors of histone deacetylases induced sprouting of dendrites, an increased number of synapses, and reinstated learning behaviour and access to long-term memories. These data suggest that inhibition of histone deacetylases might be a suitable therapeutic avenue for neurodegenerative diseases associated with learning and memory impairment, and raises the possibility of recovery of long-term memories in patients with dementia.     

突触可塑性与学习记忆

以LTP为例,通过综述前人实验及理论,对突触可塑性的两种表现形式:即结构可塑性和 传递效能可塑性与学习记忆的关系进行了研究.突触可塑性被认为是学习记忆的神经学基础,而其 中最受人们关注、研究最多的是突触传递的长时程增强(LTP).     

试析记忆与教学

由于记忆会对学生学业成绩产生重要影响,所以心理学研究者普遍关注认知学习领域中与记忆相关的内容。本文从教师的实际教学工作出发,通过对记忆相关概念的阐述,明确记忆与学业的关系,分析影响个体记忆能力的因素,使教师在具体教学过程中,针对教学内容及学习者自身的情况,结合影响记忆力的因素,找出最适合的教学方法,最大限度的提高学习者的记忆效率,从而达到提高学习成绩的目的。     

TCP1 complex is a molecular chaperone in tubulin biogenesis.

A role in folding of newly translated proteins in the cytosol of eukaryotes has been proposed for t-complex polypeptide-1 (TCP1), although its molecular targets have not yet been identified. Tubulin is a major cytosolic protein whose assembly into microtubules is critical to many cellular processes. Although numerous studies have focused on the expression of tubulin, little is known about the processes whereby newly translated tubulin subunits acquire conformations that enable them to form alpha-beta-heterodimers. We examined the biogenesis of alpha- and beta-tubulin in rabbit reticulocyte lysate, and report here that newly translated tubulin subunits entered a 900K complex in a protease-sensitive conformation. Addition of Mg-ATP, but not nonhydrolysable analogues, released the tubulin subunits as assembly-competent protein with a conformation that was relatively protease-resistant. The 900K complex purified from reticulocyte lysate contained as its major constituent a 58K protein that cross-reacted with a monoclonal antiserum against mouse TCP1. We conclude that TCP1 functions as a cytosolic chaperone in the biogenesis of tubulin.     

川芎嗪促进大鼠学习记忆作用的研究

采用川芎嗪对东莨菪碱所致大鼠学习记忆障碍的改善作用进行了研究,并进一步探讨其可能的作用机制.实验结果表明:东莨菪碱是中枢性抗胆碱药,能使训练后大鼠的获得性学习记忆成绩下降;毒扁豆碱是胆碱酯酶抑制剂,能促进中枢乙酰胆碱含量,拮抗东莨菪碱所致健忘;川芎嗪高剂量(20mg kg)能提高致健忘大鼠学习记忆成绩的正确率,统计处理结果有显著性意义(P<0 05).川芎嗪改善由东莨菪碱所致大鼠的记忆障碍,其机制可能是激活胆碱能神经系统的活性,提高脑内乙酰胆碱的含量.     

神经化学物质与学习记忆的研究进展

综述了近年来科研领域中学习记忆的进展,着重阐述了与学习记忆有关的几种物质,如神 经肽、激素、NO、神经活性因子等对学习记忆的作用     

核桃油对小鼠学习记忆能力的影响

以不同剂量核桃油给小鼠灌胃,每天1次连续2周,在被动回避装置上测定小鼠的跳台潜伏期(SDL)和逃避潜伏期(EL),在复杂迷宫上测定小鼠的觅食时间.结果显示,核桃油可使SDL延长30.4%~102.5%,使EL缩短35.3%~58.9%,使迷宫觅食时间减少3.3%~37%,并能明显改善NaNO2和乙醇引起的记忆损害;表明核桃油可明显改善小鼠学习记忆能力.     

肝源性磷脂对小鼠学习记忆及海马窖蛋白-1表达的影响

以昆明种小鼠为研究对象,利用跳台实验、旷场实验和免疫印迹杂交等方法研究了肝源性磷脂对于增强小鼠学习记忆和空间探索能力的影响.结果表明:与对照组相比,预先给予高剂量肝磷脂补充可以显著提高小鼠的学习记忆以及空间探索能力;Western Blot结果显示,与正常组相比高剂量肝磷脂补充组小鼠脑内海马区Caveolin-1和PKCα蛋白的表达量明显升高.结果提示,肝源性磷脂可以通过激活Caveolin-1蛋白和PKCα蛋白的表达增强小鼠的学习和记忆能力.     

基于情景记忆和元学习的机器人运动技能获取

针对机器人在少样本学习时利用以往的经验知识来指导新任务学习的问题,采用情景记忆建模机器人的经验,提出一种情景引导下基于元学习的机器人技能学习方法,实现机器人对新任务少样本情况下的高效学习.集成情景记忆对机器人经验建模,在学习过程中通过编码器将元学习器传递过来的任务经验存储为情景记忆,在指导新任务学习过程中通过键值特征向...     

重复性经颅磁刺激对吗啡依赖小鼠学习记忆的影响

研究1 Hz rTMS对吗啡依赖小鼠学习记忆的影响,初步探讨1 Hz rTMS治疗吗啡依赖的机制.40只ICR小鼠随机分为正常对照组、1 Hz对照组、吗啡依赖组和1Hz治疗组.建立吗啡依赖CPP模型后,采用1 Hz rTMS对1Hz治疗组进行治疗.治疗后采用Morris水迷宫实验,检测小鼠学习记忆能力的改变.结果显示,与吗啡依赖组相比,1 Hz治疗组的潜伏期显著增加（P<0.05）;但穿越平台次数、平台所在象限停留时间、平台所在象限游泳距离和平台所在象限游泳距离与总游泳距离比率均无显著改变（P>0.05）     

仁茹的毒性和药效学研究

研究仁茹提取液的急性和长期毒性,并研究了它对小鼠学习记忆的影响.分别采用小鼠经口灌胃和大鼠90 d灌胃给药的方法研究急性和长期毒性,通过跳台法进行药效学研究结果表明小鼠口服的最大耐受量为50g·kg-1;3个剂量组与对照组动物在试验期限活动正常,无死亡;体重增长状况基本一致,血常规、肝、肾功能化验结果未见明显差异;采取多种模型证实其具有改善小鼠记忆的作用仁茹提取液无明显毒性和副作用且能改善学习记忆能力.     

超声清洗空化噪声对大白鼠学习记忆影响的研究

探讨了超声清洗空化噪声对大白鼠学习记忆能力的影响．将20只大白鼠随机分为实验组和对照组，每组10只，实验组置于工作频率为20kHz、功率为600W的超声清洗机辐射出的空化噪声环境中，每天8h，共14d．通过水迷宫实验，观察其学习和记忆指标．结果显示，超声清洗空化噪声可使大白鼠学习记忆能力下降，随作用时间延长，大白鼠疲倦、迟钝等反应加重，体重增长变缓．