① 神经发育同时受内外信号调控,很多外周信号影响精神疾病的发生; ② 在焦虑、抑郁、认知缺陷和自闭症中,肠道与大脑联系密切; ③ 在产前和产后,来源于肠道菌群的分子信号等关键环境因素,影响健康且功能健全的大脑发育; ④ 肠道菌群影响血脑屏障、髓鞘、神经形成,小胶质细胞成熟等基础性神经发育进程,调控动物的多种行为; ⑤ 本文系统讨论神经发育与菌群的生物学交集,探讨肠道细菌如何参与神经系统发育和功能并平衡精神健康与疾病。 参考文献: Title: The Central Nervous System and the Gut Microbiome DOI: 10.1016/j.cell.2016.10.027 Abstract: Neurodevelopment is a complex process governed by both intrinsic and extrinsic signals. While historically studied by researching the brain, inputs from the periphery impact many neurological conditions. Indeed, emerging data suggest communication between the gut and the brain in anxiety, depression, cognition, and autism spectrum disorder (ASD). The development of a healthy, functional brain depends on key pre- and post-natal events that integrate environmental cues, such as molecular signals from the gut. These cues largely originate from the microbiome, the consortium of symbiotic bacteria that reside within all animals. Research over the past few years reveals that the gut microbiome plays a role in basic neurogenerative processes such as the formation of the blood-brain barrier, myelination, neurogenesis, and microglia maturation and also modulates many aspects of animal behavior. Herein, we discuss the biological intersection of neurodevelopment and the microbiome and explore the hypothesis that gut bacteria are integral contributors to development and function of the nervous system and to the balance between mental health and disease. All Authors: Gil Sharon,Timothy R Sampson,Daniel H Geschwind,Sarkis K Mazmanian
近期有关肠道微生物的研究非常多,已经来不及看了。人们意识上认为肠道微生物对人体很重要,而抗生素能够杀死肚子里的微生物,使用抗生素对肠道微生物是不友好的。并且,由于抗生素的滥用,多种耐药性基因开始在全球蔓延。但是,最新的的研究显示: 抗生素是调节肠道微生物的有效方法,通过抗生素调节肠道微生物可能治疗 阿尔茨海默病。 图片来自网络 7月21日,芝加哥大学的研究人员发现用广谱抗生素长期治疗能够使小鼠的淀粉样蛋白斑块减少,同时激活了中枢神经系统的炎症性小胶质细胞。 相关研究结果发表在 Scientific Reports 上。 阿尔茨海默病有两个关键特征:第一,脑内β—淀粉样蛋白斑块的积累;第二,在中枢神经系统负责免疫系统功能的小胶质细胞出现炎症。β—淀粉样蛋白斑块的形成对阿尔茨海默病的发病起主要作用,而有研究认为神经炎症状态会影响阿尔茨海默病导致认知下降的速率。 图片来自网络 在这项研究中,研究人员给转基因的 APPSWE/PS1ΔE9阿尔茨海默病模型小鼠,分别使用了无菌水和包含八种抗生素的高剂量广谱抗生素:庆大霉素(1毫克/毫升),万古霉素(0.5毫克/毫升),甲硝哒唑(2毫克/毫升),新霉素(0.5毫克/毫升),氨苄青霉素(1毫克/毫升),卡那霉素(3毫克/毫升),粘菌素(6000 U /毫升)和头孢哌酮(1毫克/毫升)的混合物,期间采集粪便细菌培养平板来检测肠道微生物的生长情况。经过长达5个月的干预后杀掉雌鼠取样,6个月时再杀掉雄鼠取样(真是“男女有别”啊!)。 抗生素处理后肠道微生物组成发生改变 首先,他们对抗生素处理小鼠的肠道微生物组成进行了分析,结果表明虽然与对照组在肠道细菌的总量上大致相当,但是抗生素处理后肠道菌群的多样性改变明显,抗生素能显著降低肠道微生物多样性(见下图)。 图片引自:Scientific Reports 6,30028 (2016) 抗生素处理后脑部淀粉样蛋白斑块明显减小 抗生素处理小鼠的脑部淀粉样蛋白斑块也出现了超过两倍的下降,而脑内小胶质细胞的炎症状态出现了显著增加。抗生素治疗后的小鼠在血液循环中的重要信号的化学物质水平也升高(见下图)。抗生素治疗后肠道菌群发生了显著变化表明肠道菌群的组成和多样性,可能通过调节免疫系统活性,减少 淀粉样蛋白斑块, 进而影响了阿尔茨海默病进展。 图片引自:Scientific Reports 6,30028 (2016) 此外, 抗生素治疗后,除了淀粉样蛋白斑块变小了,大脑中的神经细胞的树突的长度减小,树突的数量增加,并且树突的节点数目也增加了(见下图)。 图片引自:Scientific Reports 6,30028 (2016) 虽然,导致上述变化的机制仍不清楚,但是该研究为进一步探索肠道菌群如何影响脑部和神经系统提供了线索。不过研究人员也表示该研究仅是理解肠道菌群如何影响阿尔茨海默病的一个开始,还需要更多研究来证明。 基于肠道微生物的健康评估和干预任重而道远 实际上,现在还不能确定是否在人体也会出现类似的结果,将这种方法用于治疗阿尔兹海默症仍需要很长时间。 由于 阿尔兹海默症的发病时缓慢的,从 大脑和中枢神经系统发生变化到临床发病至少需要15到20年的时间。如果在这个过程中我们能够通过检测肠道微生物的组成,提前预知或评估中枢神经系统的健康状况,那就可以在病人还没有出现临床症状时进行提早干预,这或许是未来预防这类神经退行性疾病的有效手段。 在将来,如果我们了解肠道细菌变化如何影响发病或进展,或者知道它们产生的分子与中枢神经系统的相互作用,掌握了肠道微生物与人体健康的规律,我们就可以建立一种新的个性化的精准医学干预方法。 任重而道远,我们一起努力! 原文出处: Myles R. Minter, Can Zhang, Vanessa Leone, Daina L. Ringus, Xiaoqiong Zhang, Paul Oyler-Castrillo, Mark W. Musch, Fan Liao, Joseph F. Ward, David M. Holtzman, Eugene B. Chang, Rudolph E. Tanzi, Sangram S. Sisodia. Antibiotic-induced perturbations in gut microbial diversity influences neuro-inflammation and amyloidosis in a murine model of Alzheimer’s disease. Scientific Reports 6, Article number: 30028 (2016) doi:10.1038/srep30028
编者按 : 肠道菌群与人类的行为、情绪有着奇妙的关联。科学家正在考虑通过改变肠道微生物来直接治疗部分心理疾病。未来人们或许可以通过吃某种益生菌从而来改善情绪,这些听上去是不是都很奇妙?尽管有许多未解之谜仍需解答,但科学家已经在通过肠道菌群调控大脑之路上迈开步伐。 编译 | 华梦艺 责编 | 叶水送 ● ● ● 上世纪70年代美国盛行这句谚语“You are what you eat”(你的身体由你的食物决定),随着近些年来人们对健康生活理念的关注,这句话也越来越多地被重提起。这句话翻译过来,大概就是你的饮食结构决定你的性格。不过,我们今天的主题并不是讨论各个地区的美食与文化,也不是讨论如何健康地吃喝,而是从另一个方面去解读这句话——“You are what kind of bacterial you have“(你体内的细菌决定了你的性格)。 这句话是有出处的,实际上来源于《美国国家科学院院刊》(PNAS)2015年发表的一篇新闻特稿——“细菌影响大脑”(Microbes on the mind),文章的主角就是“肠道内的菌群军团”。 用“军团”这样的词语来定义我们肠道菌群,绝不是危言耸听。定居在肠道中的菌群数量惊人,它们是人体自身细胞总数的10倍多,而这些菌群编码的基因数也远超人体基因总数。这些体积微小的细菌,几乎占据了胃肠道表面粘膜的每一寸“领土”。研究显示,胃以及其内容物中所含有的微生物细胞约为1000个/克,盘区折叠的小肠中的微生物高达每克 10 3 - 10 7 个细胞的水平,而产生和储存粪便的结肠则俨然是这些微生物生活的“乐园”,这里的微生物数量高达 10 12 个/克。难怪有人戏称,我们=10%的人体细胞+90%的细菌,更有人认为,也许这些菌群才是人身体真正的主宰。尽管这些都是玩笑,近期一系列的研究发现:肠道菌群与人类的行为情绪有着奇妙的关联。 曲径通幽——肠道菌群与大脑有着奇妙的关联 2014年,美国神经科学学会围绕“大脑-微生物组关系”主题,召开了一次史无前例的研讨会。美国国立精神卫生研究所(NIHM)拨款100万美元用以资助这一研究项目,而美国海军研究局则计划在2016年9月之前,将此项研究资金增加至330万美元。有了经费的支持,相关研究者们都“鼓足干劲、力争上游”,形式一片大好。不过在大家真正接受“体内微生物影响大脑”这个“前卫”的观点之前,先驱者们的探索之路并没有现在这样顺利。 2013年,加拿大麦克玛斯特大学精神病和运动神经学系简·福斯特(Jane Foster)教授在《Neuroastroenterology and Motility》杂志上发表了一篇肠道微生物相关的文章。关于这篇文章,Foster教授是这样描述的,“迄今为止,这是在我所有发表的文章中,经历最为曲折的一篇。”这篇名为《无菌小鼠表现出焦虑行为的减轻症状与中枢神经中化学物质改变的关系研究》文章,从2011年接收到正式发表,花了整整两年时间,期间也是争议不断,受到很多审稿人的质疑。对大部分中规中矩的神经学以及微生物学研究者来说,肠道微生物直接影响大脑的推断,实在令他们难以接受。 不过,好在科学家们通常都随时准备拥抱惊世骇俗的科学新发现。在这之后,关于“肠内菌群影响大脑”的研究,大部分论文发表都比较顺利。“时代一直在进步,”福斯特教授表示。目前她的大部分文章在经过严格审查后,一般只需4至6个月就能顺利刊发。 越来越多的科学探索者寻找到了“菌群-大脑”关系网络的蛛丝马迹,各种各样的研究结果都暗示着细菌以及它们的附属产物可能对大脑有着不可忽视的影响。“肠道微生物影响我们身体代谢这个观点对于很多人来说,直觉上都是可以接受的。”美国人肠道菌群工程(American Gut Project)的创始人罗伯·奈特(Rob Knight)这样认为。不同于大部分实验抽样调查的原则,该项目接收所有志愿者提供的信息。参与的志愿者需如实填写饮食、健康和抗生素使用情况的调查表,并使用实验室提供的试剂盒挑取口腔、面部以及排泄物中的微生物。当他们将这些邮寄到实验室后,会得到一份关于体内微生物的报告,一个属于他们自己的“二维码”,用来存储和读取自身的微生物信息。 肠道菌群怎样对大脑“发号施令” 大部分对肠道微生物-脑的研究受到2004年日本九州大学Nobuyuki Sudo等人研究的启发。他们发现,在无菌状态下出生以及成长的小鼠面对压力时通常会更敏感。 研究人员将无菌小鼠和正常小鼠暂时性放置于同一个封闭空间中一段时间后,检测两组小鼠血浆中应激激素水平发现,面对暂时的压力,和人类相似,两组小鼠血浆中的应激激素-促肾上腺皮质激素和皮质酮水平都有显著提升。不过相比于正常的小鼠,无菌小鼠体内应激激素水平升高将近两倍。 从出生就一直生活在无菌环境中的小鼠,是研究细菌对大脑影响的理想模型。图片来自Caroline Westwater 这些有趣的实验引起了广泛的关注。一些研究结果表明,无菌小鼠大脑皮质以及海马区的神经生长因子(BDNF)低于正常小鼠的水平,其他相关的神经化学系统在无菌小鼠中似乎也受到一些影响,但这些系统究竟发生了怎样的变化,研究者还不能给出一致的结论。这些零碎却有力的实验结果,已经让大脑与肠道菌群连接的通路依稀可见,然而行为学实验结果却成了这条轮廓初现道路上的新障碍。 尽管在之前的应激实验中,无菌小鼠体内的应激激素水平显著高于正常小鼠,但在行为学实验中,这些小鼠却表现的更加“气定神闲”,它们似乎更喜欢待在暴露的场所。这对天性谨慎胆小的小鼠来说,算是“无菌小鼠不怕虎”。 为了更好地理解肠道菌群这个“庞大的军团”究竟如何给远在“千里之外”的大脑“发号施令”,研究者通过细菌转染实验人为地改变了肠道菌群的组成。在众多的相关实验中,麦克马斯特大学的约翰·克莱恩(John Cryan)研究团队通过给肠道菌群军团 “大换血”,让几只胆小羞怯的小鼠成功转型为骁勇善战的“冒险家”,例如将生性胆大的NIH Swiss型小鼠的肠道细菌移植到天生纠结犹豫的BALB/c型小鼠体内,三个星期后,BALB/c型小鼠摇身一变成了果断骁勇的“骑士”。更有趣的是,当NIH Swiss型小鼠移植了胆小的BALB/c型小鼠细菌后,前者居然花了比平时三倍多的时间才谨慎地从实验台上走下来。 除了将不同菌群转染至小鼠,研究者们还进行了一种更“偷懒”的方法:直接给小鼠喂食不同种类的菌株,这样“简单粗暴”的实验方法很快有了收获:喂食长双歧杆菌以及短双歧杆菌的小鼠面对焦虑时,应激反应强度均会出现不同程度的降低。当然这两种细菌对小鼠性情进行了不同的改造:短双歧杆菌让小鼠变得更加勇敢,而长双歧杆菌则让小鼠在面对压力时,体温不至于变化过快。 为什么科学家们要如此大费周章去解开细菌、行为以及生化过程改变之间的种种谜团? 其中一个重要的动机应该是科学家想通过改变体内微生物从而直接治疗部分心理疾病。当然,相关的体内微生物学研究已经有一些发现:微生物对于和压力与焦虑相关的神经回路的影响可能集中在一些关键的发育阶段。巧合的是,在干预治疗部分心理健康疾病时,也有几个非常关键的时期。例如,自闭症的发生很有可能源于大脑早期发育过程中的一些尚未解决的问题,而精神分裂症的发生(至少一部分)是由青少年以及成年早期脑部成熟过程中的缺陷引起。如果体内微生物确实被证明在大脑发育的敏感阶段扮演了重要的角色,那么微生物未来作为治疗心理健康疾病靶点的可能性也将大大提升。 事实上,已有证据证明细菌可能影响早期脑部回路及功能。研究者们发现,在无菌小鼠中转入相应的肠道细菌可改变一些异常的行为,但这种处理只有在10周龄前才能起作用。Sudo等人的研究发现,无菌小鼠体内过高的应激激素也可以被小鼠6周龄时转入的细菌逆转,但同样的处理,对14周龄的小鼠就已失效了。这些结果在提示我们,体内菌群的存在或缺失对塑造与焦虑压力相关的神经回路起到非常关键的作用。然而,一旦这些回路在无菌小鼠体内以错误的方式建立,即使后期再使用相关细菌进行干预恐怕也是无力回天。 当然,小鼠宝宝和我们人类一样,大部分肠内菌群来自于分娩时母亲阴道中的微生物。因此,我们不难想到,孕期母亲体内的菌群结构会影响到后代脑部发育等过程。宾夕法尼亚大学的神经生物学家特蕾丝·贝尔(Tracy Bale)通过研究发现,当小鼠在怀孕早期承担较大压力时,它们阴道中的乳酸杆菌数量会有所降低,所产下幼鼠的肠道中的菌群也会表现出相同的变化,而这些鼠宝宝的大脑中,一些和神经发育相关的氨基酸也会“减少供应”。 想要好情绪,得先填饱你的胃 除了Bale团队的实验,加州理工学院的Sarkis Mazmanian团队的实验也有不小的收获。他们给一群有类似人类抑郁症症状的小鼠喂食一种人类肠道特殊的菌株:脆弱拟杆菌,饲养一段时间后发现它们肠漏气状况(部分患有自闭症的人也会有此症状)有所好转,同时一些明显的焦虑行为(如不断的重复性行为)也会减轻。不过,加州理工学院的马兹马尼扬(Sarkis Mazmanian)也表示“谁知道这些小鼠是不是真的有自闭症呢,也许我们只是被表面现象欺骗了。” 其实,即使弄清楚小鼠是不是真的有自闭症,我们还需要解决一个更加关键的问题——这些从小鼠实验中得到的数据,要用到人类身上还有千里之遥。不过,科学家们的辛勤工作也获得了一些诱人的成果。在一项实验中,55名志愿者在连续服用瑞士乳杆菌和长双歧杆菌混合的益生菌一个月后,相对于只服用安慰剂的志愿者来说,他们的沮丧、愤怒以及不友好的情绪都有所降低。 看到这样的结果,如笔者这样脾气不够温和的吃货简直坐立不安——也许可以通过吃吃吃来让自己变得温柔些。不过,严谨的科学家立刻告诉你我——先别急着去吃益生菌啦,也许这只是由于益生菌的过渡宣传引起的安慰剂效应。而且他们还告诉我们一个更残忍的现实,目前很难有证据去证明现有的益生菌对身体健康有显而易见的好处。“大部分的细菌实际上对于我们的行为举止都没有积极作用,不过这并不代表它们对我们有害,只是没啥作用罢了。”爱尔兰科克大学的克莱恩教授表示,“想要知道哪些益生菌是如何发挥功效的,我们必须要弄清楚这些细菌会产生什么物质以及它们细胞壁的成分。” 事实上,要想弄明白体内的细菌究竟是如何“遥控”大脑,我们仍需要克服很多困难。不过,这样研究有积跬步至千里之感,仅仅解决这些问题中的一小部分,都足以让我们在“肠-脑”研究之路上迈出一大步。 参考文献: 1.Shen, H. H. (2015). News feature: microbes on the mind.. Proceedings of the National Academy of Sciences of the United States of America, 112(30), 9143-5. 2.Foster, J. A., Neufeld, M. V. (2013). Gut–brain axis: how the microbiome influences anxiety and depression. Trends in Neurosciences, 36(5), 305–312. 3.Felix, S., Fredrik, B. (2013). The gut microbiota--masters of host development and physiology.. Nature Reviews Microbiology, 11(4), 227-238. 您也可以现在测测自己的 肠脑健康状况 哟,提前 了解自己的肠脑健康状况,预防帕金森 的发生吧。点击如下链接,或扫描下方二维码: https://www.wenjuan.com/s/FFFRN3/
【良心剧透】 想靠节食瘦下去?当心饿胖了自己。 (图片来源: 可可亚的图文志 ) “少吃点”大概是有史以来最流行的减肥方案了,应该没有之一。“迈开腿”太累,“管住嘴”貌似简单些,只需要对自己残忍一点。况且这个方案所依据的理论逻辑无死角——只要吸收的热量小于消耗的热量,收入小于支出,减肥就只是个时间问题而已。运动少、消耗少,没关系,吃的更少就可以了。是不是太简单了啊亲?果真如此,满大街划过的早只剩下一道道闪电了,哪里还有胖子?事情的真相才总是冷艳又骨感。想靠节食瘦下去的你,当心饿胖了自己。 节食这件事情,可不是咬紧牙关对自己狠点那么简单。你当然可以对自己各种残忍,但是,控制身体对热量的“收入”和“支出”这件事,不是由你控制的,而是你的大脑。我们还都生活在水里的时候,大脑就开始陪伴我们一起玩耍了。人的精力总是有限的,要吃火锅要唱歌,于是在上亿年共同玩耍的过程当中,我们把越来越多日常琐碎的事情都放心的交给了大脑去打理,比如喘气,比如提醒小主您再不用膳恐怕就不需要再用膳了,再比如,我们的体重。 简单说,经过千百万年的工作积累,我们的体重“该”有多重这件事基本上已经不是我们自己能做主的了。说的再准确一些,我们的体重能有多“轻”这件事,已经不是我们自己能做主的了。大脑自从接手打理体重这份工作之后,就一直遇到一个让他很头疼的问题:饭总不够吃,小主们一不小心就被饿死了。于是在一次次的失败挫折当中大脑不断积累经验,苦心钻研,终于悟出了体重管理工作的指导原则 (1) :维稳压倒一切!不能太瘦,瘦了挨不过饥荒;也不能太胖,胖了怕跑不过狮子。大脑在我们成长的过程中踏实调研,全面总结,结合代代相传的经验,亲自确定这个“不胖不瘦刚刚好”的体重范围,然后启动一整套自主研发的高科技装备 (2) 来维持我们的体重。大脑认定的这个“刚刚好”的范围因人而异,总体来讲,大约就是我们平常体重上下波动几斤的样子,不会超过平常体重的 10% (3) 。也就是说,你可以少吃一点,让体重降那么个把斤的。你也可以一直少吃一点,让体重一直降那么个把斤的。但是,如果你超出了大脑给你划定的范围,哼哼,接招吧。 先感受一下大脑的硬功夫,开源节流。当你把体重饿到逼近大脑允许的下限值时,你的身体就“不需要”再吃原来那么多了。原来得吃两碗饭才能做完的事情现在可能一碗饭就够了 (4) ,同时,原来三顿饭才能吃够一天需要的热量,现在可能两顿饭就够了 (5) 。这件乍一看好像还挺乐观的事情有什么杀伤力呢?你需要比饿瘦的时候对自己更残忍才有可能保持瘦下去(不是变得更瘦,是保持饿瘦的效果)。科学家们通过试验测试了这个招数的杀伤力。他们在试验中残忍的通过饮食控制各种小动物和人类志愿者的体重,先喂肥他们,再饿瘦他们,在这个过程中引诱大脑出手,然后观察中招前后的变化。粗略来说,假设一个平均体重的妹子辛辛苦苦饿瘦自己之后中了这招,想要保持之前饿瘦的战果,她每天都得比饿瘦自己的时候再少吃一袋薯片,或者两三个肯德基辣鸡翅,或者两三瓶啤酒才有可能成功 (6) ,每天,直到放弃。否则?当然是没有少吃的那部分化作肉肉找回家喽。出招的整个过程中,大脑当然不会让你察觉到一丝一毫的变化。更厉害的是,这招是童叟无欺的无差别乱打,不管是是你胖是瘦,男女老幼,只要中招,一个下场。江湖也有传说,打胖子打得更狠一些 。 怎么你说你是个任性的胖子,就是对自己够残忍?幼稚。再感受一下大脑的软刀子,专制任性。请注意,刚才说了半天,不需要吃原来那么多的是你的“身体”,不是你。相反,在大脑强大的“宣传”攻势下,你比原来饿得更快,饿得更猛烈,饿得更凶残了,尤其是饥饿的妹子们 。因为饿,你变得更加焦躁不安,百爪儿挠心,对食物的感知能力比原来更加敏锐了 ;因为饿,舌尖上的记忆一个一个变得更加鲜活起来 ;因为饿,甜滋滋、油腻腻的东西开始让你浮想联翩 ,就连原来不喜欢吃的东西也开始变得可爱了 ;因为饿,你食欲大增,胃口大开,除了诱惑可以拒绝一切。从一元换大杯到自助随便吃,崩塌分分钟开始,你却压根不会意识到任何“危险”的存在 ……这一切,都在大脑默默的掌控之中。 面对这么一位战斗力爆表的对手,你还任性得起来么?无数先烈与大脑长期的斗争经验告诉我们,顽抗到底是没有用的。不管你怎么任性,只需要一年左右的时间,大约 50%饿掉的肉肉就会重新再长回来 ,2-5年之后之前的战果就已经所剩无几了 ,甚至有一半左右的人会比5年前开始减肥的时候更胖 。换句话说,想靠节食减肥的你,很有可能最后饿胖了自己。 大脑这么冷酷无情当然不是因为他不解风情把握不住时尚的潮流,实在是因为我们生活的环境太艰辛了。在几百万的漫长进化过程当中,一次又一次地看着你被活活饿死却无能为力,这让大脑非常的失落与自责,所以才会对饥饿这件事情这么敏感。还不都是为了你好。 看到这儿你可能会问:骗子,你刚才说的是维稳!大脑那么厉害怎么没见我吃多长肉的时候他把我拽回来?嗯……这件事情,其实,怪我们自己。对咱们大多数人来说,彻底的衣食无忧也就是最近一两百年的、甚至几十年的事情。现在我们知道吃不完的东西可以放在冰箱里留着明天再吃,但是在这之前那段相当长的忍饥挨饿的日子里,尽可能吃掉多余的食物把它们变成脂肪贴在身上才是更加保险的粮食安全策略。对人类是这样,对动物也是这样。但是小动物们多件事情需要担心,吃得太胖就很可能就会变成脂肪贴在别人的肚子上了 。咱们人类可就不一样了,枪拳棍棒丈八矛,斧钺勾叉青龙刀,一十八般兵器七十二路绝学,加上烟花爆竹连年兽都不怕,还担心这些小野味儿么?太久没有天敌的幸福生活不但让大脑慢慢生疏了控制我们体重上限的手艺,甚至产生了“你们人类明明是越胖越好嘛”的奇怪想法 (7) 。所以,残酷的现实就是,前面提到的那个“不胖不瘦刚刚好”的范围,是会随着体重的稳定升高而不断升高的——在大脑的高压恐怖下,你很难坚持饿瘦自己,但是可以不断吃胖自己。更残酷的是,我们现在生活的环境,不论是随处有方便吃的餐饮服务,还是白天坐晚上卧的生活习惯,都是分分钟崩坏你节食战果,增加你脂肪储备的幸福天堂 。当然,大脑们是很开心的。再也不用担心你被饿死了。 【注】 1) 大脑时刻监控调节着我们体内的能量平衡( Energy Homeostasis),也就是我们通常想要减肥的时候所说的能量的摄入量与消耗量之间的平衡。但是大脑的目的与我们想减肥的目的相反,是通过对身体各器官的摄入量和消耗量的调节,把体重和体内的脂肪组织维持在一个相对稳定的范围内。这套系统7x24小时的运转着,所以,对我们大多数人来说,体重是相对稳定的。也因为我们的体重莫名的稳定(尤其是减不下去),科学家们才针对体内的能量平衡控制机制做了大量的研究工作 。 2) 下丘脑是大脑用来调节机体能量内稳恒状态的核心器官 。人类的下丘脑大约有杏仁那么大,藏在大脑的下部,脑干上方,个头虽小,却是负责调节我们内脏和内分泌活动的高级神经中枢。上个世纪中叶,科学家们发现下丘脑是从生理上控制食欲、饥饿感以及能量平衡的核心器官 。但是,下丘脑可不是一个人在战斗。很快,科学家们发现大脑不仅仅是靠直接调节能量平衡来阻止节食的,大脑中也不仅仅只有下丘脑这个神经中枢参与了抵抗节食的行动。跟下丘脑并肩作战的还有会影响感官(视觉、嗅觉、味觉),甚至情感(喜欢、渴望、想象力、记忆力)的神经系统 。当我们通过节食减肥,并试图保持战果的时候,大脑中的这些小伙伴们就会使出浑身解数,软硬兼施,破坏我们的减肥成果。 3) 关于这个 “刚刚好”的范围到底是多少,科学家们提出了很多理论想要找到确切的答案,不过到现在也还是个让人头疼的问题。你可能听说过设定点理论(SetPoint)。没错,这是科学家发现人们的体重特别稳定之后提出的第一个理论 。但是很快就遇到问题了。设定点理论可以解释为什么我们瘦不下去,却解释不了我们为什么能一直胖下去。于是之后又有很多新的理论对设定点进行了修正和补充,并且把环境因素与基因的差异也考虑了进来 。但是这些新的理论都是为了找出为什么我们能一直胖下去的原因与应对策略。关于为什么我们饿不瘦自己,科学家们经过无数次的试验早就基本达成共识了。所以,很遗憾,想靠饿减肥,真的很难。 4) 饿瘦的时候,大脑会发出指令提高肌肉的做功效率。效率提高了,维持日常活动消耗的能量就减少了,节省下来的部分就会变成脂肪被储存起来 。 5) 饿瘦的时候,大脑也会发出指令提高身体对热量的吸收效率,同时提高热量到脂肪的转换效率。这样即使我们吃得比原来少了,仍然可能胖的反而比原来更快 。 6) 很多科学家都通过试验测量了大脑对体内能量平衡的调节能力。总体来说,通过节食减肥超过正常体重 10%的人平均每天比正常需要少消耗300-400千卡的热量 。比如哥伦比亚大学的Leibel教授,他在一次研究中残忍地通过饮食控制了一群志愿者的体重(有胖子,也有从没胖过的人),先喂肥他们,再饿瘦他们 。在这个过程中,Leibel教授发现当体重通过节食减轻10%或以上的时候,胖子们的日平均能耗减少了3-13千卡/公斤瘦体重(瘦体重就是除去脂肪组织之后的体重),从没胖过的测试对象的日平均能耗也降低了3-9千卡/公斤瘦体重。这是个什么概念呢?根据咱们2010年的国民体质监测公报,中国成年女性的平均体重是60公斤左右。成年女性的体脂正常体脂含量大约是25%。也就是说,假如一个平均体重的妹子辛辛苦苦把自己饿到了54公斤,大脑会强行让她每天少消耗130-580千卡的热量。把这些热量换算成常见的食品差不多就是文章里那些个例子啦。 7) 在长期的进化过程中,这种人类独有的生存选择压力(长期处于饥荒环境中,但是没有天敌的压力)让我们的身体更倾向于保留利于储存热量的基因,以及利于防止饥饿的调节机制 。比如你可能听说过“瘦素”(Leptin)这个东西,它是大脑专门用来监控体重和脂肪储备的信息素,也是被研究最多的信息素之一 。瘦素本身确实可以抑制食欲、增加能量消耗、抑制脂肪的合成来防止发胖(所以叫瘦素)。但是,在咱们人类身上,瘦素只有在低水平状态的时候才会发挥强大的调节作用,恢复到正常水平之后就没有什么更明显的效果了 。换句话说,经过长期的进化选择,我们的瘦素现在只关心你会不会饿瘦了。至于会不会变成胖子,它不感兴趣。顺便说一下,你知道瘦素是谁发给大脑的信息吗?脂肪!知道了吧,裁判员和运动员是一伙儿的。你还想轻松能赢? 【参考文献】 Speakman, J.R., Levitsky, D. 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Mann, T., Tomiyama, A. J., Westling,E., Lew, A. M., Samuels, B., Chatman, J. Medicare's search for effectiveobesity treatments - Diets are not the answer. Am. Psychol. 2007,62:220-33. Speakman, J. R. Thrifty genes forobesity and the metabolic syndrome--time to call off the search? Diabetes vascular disease research : official journal of the International Society ofDiabetes and Vascular Disease. 2006,3:7-11. Prentice, A. M., Rayco-Solon, P.,Moore, S. E. Insights from the developing world: thrifty genotypes and thriftyphenotypes. Proceedings of the Nutrition Society. 2005,64:153-61. Hofbauer, K. Molecular pathways toobesity. International Journal of Obesity. 2002,26:S18-S27. Shin, A. C., Zheng, H. Y., Berthoud, H. R. An expanded view of energyhomeostasis: Neural integration of metabolic, cognitive, and emotional drivesto eat. Physiology Behavior. 2009,97:572-80.
一项15年的研究表明,冥想可以让大脑的结构和功能发生变化。长期修炼冥想会导致大脑前叶和脑岛体积增大约10%;同时冥想者的注意力更集中,更能够释放压力。严格的科学证据证明,冥想对提高人的生活质量(精神和体质)很有帮助,降低了人体细胞的老化进程,可以延年益寿。 详情请参考 Matthieu Ricard, Antoine Lutz and Richard J. Davidson,Mind of the Meditator,Scientific American, November 2014 Volume 311, Number 5, p38-p45. 科学家正在测试冥想者(上图),冥想者大脑增加区域(下图)。全部图片来自《科学美国人》。
导语: 由于科普弱视相关知识的力度不够,很多家长不仅将弱视和其它眼疾(例如:近视)混为一谈,而且低估了弱视的危害性,给未能及时治疗的弱视儿童造成了严重的生理和心理伤害。 概念: “弱视”主要指一种在没有明显器质性病变情况下,矫正视力达不到和发育期相符视力值的功能性为主导的疾病。 解读: “弱视”中的这个“弱”字,已经很直观地描述了弱视和大脑视觉功能低下存在紧密的联系。这一点不仅体现在其命名上,也体现在弱视的相关临床表现上。 一、视力无法被矫正,例如:弱视患儿即便戴镜子,甚至离被观察物体很近,也无法看清【下图】。为了直观地描述这一点,我们称之为“视网膜模糊化”。 二、存在对比敏感度、位置锐度、立体视觉等损害,使得 弱视患儿在阅读速度、阅读准确性、阅读流利性和正常儿童存在明显的差异,例如:丢行缺字、没有兴趣等异常现象。 可是,由于科普弱视知识的力度不够,缺乏相关知识了解的家长往往将这些异常现象误解为孩子调皮或者没兴趣,并给予斥责。 三、形态和机能之间的关系是弱视研究中不可被忽视的问题。虽然弱视被认为是以功能性为主导的症状,但也往往同时存在器质性病变,例如:屈光系统异常、眼动系统异常等,形成多种不同类型的弱视,例如:屈光不正性弱视、斜视性弱视等等。对此,我们以病理性远视形成为例来说明这一问题, 当新生儿出生后,由于视觉器官尚不成熟,会存在一定的生理性远视度。伴随年龄的增长,视觉器官(主要指屈光系统)会逐步生长,例如:眼轴长度从最初出生的18mm生长到成熟期的24-26mm。在这个眼轴生长的过程中,生理性远视度会逐步下降,并直至消失殆尽,成为正视眼。可以说,从远视眼向正视眼的转变过程是屈光系统生长的一个重要标志。 由于视觉器官生长和视觉功能发育之间存在紧密联系、不可分割的关系,当大脑视觉功能被抑制并形成弱视时,视觉器官形态生长也会被相应地抑制。 例如:眼轴生长速度减慢,生理性远视度的下降速度也相应地减慢,甚至停止,最终转变为病理性远视。 另外,和正常人相比,远视(屈光不正性弱视)患者的眼球偏小,是眼球生长被抑制的直观表现。 总结: 弱视不仅是一种眼病,而是也是一种和大脑视觉神经中枢损伤有关的脑病(Amblyopia is not only the problem with eye, but aloso is the problem with brain, especially for the impairment of primary visual cortex)。无论是弱视的以上临床表现,还是以VEP(Visual evoked potential)等视觉电生理的深入研究,均有力地证实了这一点。由于弱视患者存在视觉功能低下,阅读能力和反应能力差,无法从事绘画、手术、驾驶等对视觉功能有高要求的职业,而且斜视外观上的异常很容易给患者造成自卑的心理伤害。因此,我们希望广大家长一定要给予足够的重视,及时进行弱视的预防和治疗工作,否则就会造成一辈子的遗憾。 其它文章: 中医治疗弱视 中医治疗斜视 中医治疗散光 中医治疗远视 中医治疗近视
我们说一个人说话“掷地有声”不是说他/她的嗓门有多大,而是其表达能够感染他人。对于一个有思想的人,他所说出来的话想必都是经过考虑的,所以才让人感觉分量十足。正所谓,思想就是执行力,近期科学家真的证明了大脑在进行思考时会变重哦! 英国雷丁大学的研究人员 Field 和 Inman 发现相比于静躺着啥也不做的人,听音乐或者不仅听音乐还看视频的人大脑变得更重了。究竟变重多少呢?通过高精度的称量,研究人员发现大脑活跃状态比不活跃状态重了0.005牛顿,相当于一个普通鸡蛋百分之一的重量。他们的研究论文“Weighing brain activity with the balance: a contemporary replication of Angelo Mosso’s historical experiment”已经发表在了国际知名刊物Brain (IF=9.915)上。 关于这个试验,其实早在18世纪末就有一个叫Angelo Mosso (安杰洛莫索)的意大利科学家发现了这个现象,当时安杰洛认为思考数学问题的人的大脑肯定比看新闻的重。时隔百年之后,有人把他的试验整理作为描述性文章同样发表在了Brain。 那么是不是大脑越重的人,思考力越强呢?虽然思考越深入,人的大脑越重,但反过来是不成立的。如,据维基问答网站介绍,男人平均大脑重量是1360g,而女人是1250g,但爱因斯坦,这个世界是最聪明的人之一大脑重量不及女性,仅1230g.
偷了很长一段时间,感觉一个人的大脑如果不经常用多半就生锈了, 可是人天性就喜欢懒散,有时很讨厌使用大脑去想问题,喜欢做一些不需要思考的事情,可是当你享受到简单的轻松时,就越发去避免脑力劳动了,这样恶性循环直接导致大脑的退化, 正如刀不磨会生锈,人不努力会落后 你现在也许不是最优秀的人,但你可以成为最优秀的人,这需要你努力去争取、奋斗 you can do it
喝牛奶可以让人更聪明吗? 诺贝尔奖的颁奖典礼已经落下帷幕,人们对科学地探索却不会停止。最近,一项发表在《实用神经学》(Practical Neurology)上的论文指出,人均牛奶饮用量越多的国家,他们获得诺贝尔奖的数量也更多 。喝牛奶会让人更聪明? 喝牛奶与诺贝尔奖有关联? 前段时间,《新英格兰医学期刊》(New England Journal of Medicine)刊登了一个研究报告指出,一个国家的巧克力消费量和获诺贝尔奖数量有关联,巧克力的人均消费量越多,获得诺贝尔奖的数量也越多,可能是巧克力中的类黄酮(flavonoids)有助脑力健康,让人更加聪明 。 由于巧克力经常和牛奶混合在一起,还有很多“牛奶巧克力”这样的食品,所以,就会让人产生联想:牛奶的饮用量是否与获得诺贝尔奖的数量存在关系呢?英国的研究人员搜集了联合国粮农组织(FAO)2007年数据,他们比较了22个国家的人均牛奶饮用量,加上“巧克力理论”作者提供的信息,进行了数据分析,得出结论认为牛奶和诺贝尔奖数量很大相关性 。 牛奶消费量与获得诺贝尔奖数量的相关性 研究人员还指出,在诺贝尔奖的国家中,平均每千万人获得诺贝尔奖的数量,瑞典最多,瑞典也是人均牛奶饮用量最高的国家,人均一年要喝掉340公斤牛奶;而在统计的另一端,中国大陆最少,同时,中国的人均牛奶饮用量也是最低,一年仅25公斤。从数据分析来看,牛奶引用量的确与获得诺贝尔奖的数量有相关性。但是究竟是什么原因呢?论文作者指出,可能是因为牛奶富含维生素D,而维生素D有利于改善大脑认知力,促进大脑健康。牛奶真的可以让人更聪明吗? 牛奶促进大脑认知?证据不足 近年来,牛奶一直被人们视为健康的食物而受人们追捧。牛奶的营养价值的确很高,牛奶含有丰富的优质蛋白质,它还有高含量的钙,同时含有利于钙吸收的维生素D。那么,喝牛奶究竟是否有利于大脑健康呢? 科学家们也做了一些研究。2010年,一项研究对8个关于牛奶饮用量与大脑认知的研究进行荟萃分析,结果发现,有2个横向研究和一个前瞻性调查的结果显示,乳制品对大脑的认知力有促进作用;但同时也有4个前瞻性调查结果显示牛奶与大脑认知力没有关系,甚至全脂乳制品的消费还可能会导致人年老后认知能力下降,主要是因为饱和脂肪酸对健康的不利影响 。从分析来看,并没有足够的证据可以证明牛奶有促进大脑认知的作用。 2012年,澳大利亚的研究人员在《国际乳品杂志》上发表了论文认为牛奶或者奶制品摄入量较高与大脑认知能力存在正相关性。这个研究对900多名23岁至98岁的成年人进行了8项关于大脑功能的测试,并记录他们的牛奶消费习惯,结果发现,牛奶或奶制品摄入量较高的成年人,在记忆及其他大脑功能测试中得分较高,他们在测试中“不及格”的比例仅为不饮或少饮牛奶者的五分之一;不管在哪个年龄段,每天至少喝一杯牛奶的人在测试中的得分均较高,排除生活方式、饮食习惯等可能影响大脑健康的因素后,多喝牛奶与大脑更健康之间仍存在关联 。 不过,这个研究还是存在很多不足,比如,该研究并没有区分究竟是哪一种乳制品,尤其是没有考虑乳制品的脂肪含量的影响,有些乳制品的饱和脂肪含量很高,比如干酪,大量研究发现,饱和脂肪不利于大脑健康。 另外,还要明确,相关性并不代表因果性。研究人员也发现,那些经常喝牛奶的人,他们其他的生活习惯也更好,平时蔬菜、水果吃的也多,而且吸烟、喝酒等不良的生活习惯也少很多;而那些很少喝牛奶的人,他们其他的生活习惯也更加不健康,他们抽烟、喝酒的次数也更多,可能这些不良生活习惯也有影响。 可见,目前的研究证据并不能证明喝牛奶可以改善大脑认知、让人更聪明。 维生素D 有益大脑?牛奶不是主要途径 喝牛奶与诺贝尔奖获得有相关性的论文推测可能是因为牛奶中富含维生素D,而维生素D是有益于大脑认知健康的。 事实上,目前的研究证据也不足以证明维生素D有改善大脑认知的作用 ,而且牛奶中的维生素D含量并不算高。维生素D是一种脂溶性维生素,它能溶解到脂肪中。食物中维生素D的来源并不丰富,只有鱼肝油、动物内脏、各种富含油脂的鱼类等。牛奶中维生素D的含量一般在5-30个国际单位之间,这个含量并不高 。如果牛奶经过脱脂了,比如脱脂牛奶,它就是几乎不含维生素D的。 另外,维生素D是所有维生素中最独特的一种,它是人体可以自然合成维生素D的,人们在接受阳光照射时皮肤可以自身合成维生素D。研究发现,紫外线照射可以促进皮肤中的7-脱氢胆固醇转换为胆骨化醇,即内源性维生素D3 。实际上,人体内的维生素D只有不到10%来源于食物,大部分都源于阳光照射。这种方法最为安全和方便,而且数量大于食物中的摄取数量。在夏天的晴朗天气下,穿着短袖衣服,每天晒太阳15-20min即可获得满足身体需要的维生素D,通常来说,只要有足够的时间接受阳光照射,人体就不需要从食物中社区维生素D。 在我国,成人维生素D的每日推荐摄入量为5-10微克,相当于200-400国际单位,在保证一定户外活动的条件下并不难达到。所以,要补充维生素D,记得多去室外活动多晒晒太阳。 适量喝牛奶有益健康 牛奶的确是一种健康的食物,但目前的研究证据并不足以证明喝牛奶可以让人更聪明,如果想补充维生素D,喝牛奶也不是最主要的途径。每天喝牛奶也是各国膳食指南提倡的健康习惯,比如,2010版《美国人饮食指南》建议成年人每天饮用3杯低脂或脱脂牛奶;中国居民膳食指南也推荐我们每天要吃300-500克乳制品。我国乳制品消费量普遍比较低,远远没有达到推荐量 。如果按照膳食指南推荐适量吃一些乳制品,对健康是有好处的,至于变聪明,那就不要过于奢望。 参考资料: 食品伙伴网.新研究:诺贝尔奖数量与喝牛奶量正相关. http://www.foodmate.net/news/keji/2013/01/222292.html Messerli F. Chocolate consumption, cognitive function, and Nobel Laureates. N Eng J Med 2012;367:1562–4. Milk, chocolate and Nobel prizes. Pract Neurol 2013;13:63 doi:10.1136/practneurol-2012-000471 Crichton, G. E., Bryan, J., Murphy, K. J., Buckley, J. (2010a). Review of dairy consumption and cognitive performance in adults: findings and methodological issues. Dementia and Geriatric Cognitive Disorders, 30, 352-361. Crichton GE, Elias MF, Dore GA, Robbins MA. Relation between dairy food intake and cognitive function: The Maine-Syracuse Longitudinal Study. International Dairy Journal, 2012, 22:15-23. Annweiler C, Allali G, Allain P, et al. Vitamin D and cognitive performance in adults: a systematic review. Eur J Neurol 2009; 16:1083–9. E Leerbeck, H Søndergaard . The total content of vitamin D in human milk and cow's milk. British Journal of Nutrition, 1980. 范志红.食物营养与配餐. 范荣静,王宝英.中国城市乳制品消费状况:对北京、上海及广州的调查.古今农业 , 2011, (4): 110-116.
2010年2月在世界著名的TED会议上美国一位女神经解剖学家Jill Taylor博士讲自己左脑中风以后,右脑的神奇"开悟"经历。 http://www.ted.com/talks/jill_bolte_taylor_s_powerful_stroke_of_insight.html 令人震惊的20分钟,值得一看! 进化学家问:大脑的左右半球分工是如此的明确,why? 神学家问:神秘体验的大脑基础是什么? 普通人问:为什么濒死体验告诉我们,不能随便移动(濒)死者的身体? 瑜伽师问:你“感受”到的,是“梵”吗? 和尚问:你的“巨大而融合”的觉受,是“无量心”吗? 生理学家问:为什么身体会同时有愉悦的体验,又对外界的刺激感到痛苦? 批评家问:你混淆了物质和精神,扰乱了肉体和灵魂的界限,有何居心? 。。。。。 Open in Google Docs Viewer Open link in new tab Open link in new window Open link in new incognito window Download file Copy link address Edit PDF File on PDFescape.com Open in Google Docs Viewer Open link in new tab Open link in new window Open link in new incognito window Download file Copy link address Edit PDF File on PDFescape.com Open in Google Docs Viewer Open link in new tab Open link in new window Open link in new incognito window Download file Copy link address Edit PDF File on PDFescape.com
2012年9月20日 讯 / 生物谷 BIOON/ --人类大脑可能是宇宙上最为复杂的物体,但是它的生长依赖于一种东西:神经元的形状。 不同类型的神经元在与哪些其他的神经元相连接在一起以及与它们在何处附着是有选择性的。人们认为特异性的信号分子在指导这种过程中发挥着至关重要的作用。 来自瑞士联邦理工学院的Henry Markram和同事们构建了大鼠躯体感觉皮质(somatosensory cortex)的三维计算机模型,并且每个模型含有在大鼠大脑中发现的细胞类型的随机组合,但不含有信号分子。然而,只需允许这些神经元产生它们正确的形状,就可以使得74%的神经元连接最终都在正确的地方形成。 这些研究结果提示着科学家们可能在不需要信号分子的存在下绘制出大脑大部分结构。对于努力绘制大脑中令人眼花缭乱的神经元连接网络的神经科学家们而言,这是一个好消息。Markram说,“它将需要花费数十年的时间来绘制大脑中的每个突触。” 人们通常认为精神分裂症是由于大脑连接存在的缺陷而导致的。这项研究可能也有助于揭示诸如精神分裂症之类疾病的病因。如果Markram的这项研究证明是对的,那么不能正确形成连接的有缺陷的神经元可能是这类疾病的一个影响因素。(生物谷Bioon.com) doi: 10.1073/pnas.1202128109 PMC: PMID: Statistical connectivity provides a sufficient foundation for specific functional connectivity in neocortical neural microcircuits Sean L. Hilla,1,2, Yun Wangb,c,1, Imad Riachia,1, Felix Schürmanna, and Henry Markram It is well-established that synapse formation involves highly selective chemospecific mechanisms, but how neuron arbors are positioned before synapse formation remains unclear. Using 3D reconstructions of 298 neocortical cells of different types (including nest basket, small basket, large basket, bitufted, pyramidal, and Martinotti cells), we constructed a structural model of a cortical microcircuit, in which cells of different types were independently and randomly placed. We compared the positions of physical appositions resulting from the incidental overlap of axonal and dendritic arbors in the model (statistical structural connectivity) with the positions of putative functional synapses (functional synaptic connectivity) in 90 synaptic connections reconstructed from cortical slice preparations. Overall, we found that statistical connectivity predicted an average of 74 ± 2.7% (mean ± SEM) synapse location distributions for nine types of cortical connections. This finding suggests that chemospecific attractive and repulsive mechanisms generally do not result in pairwise-specific connectivity. In some cases, however, the predicted distributions do not match precisely, indicating that chemospecific steering and aligning of the arbors may occur for some types of connections. This finding suggests that random alignment of axonal and dendritic arbors provides a sufficient foundation for specific functional connectivity to emerge in local neural microcircuits
寻正 我经常看美国喜剧《乔治*罗泊斯》(George Lopez),该剧最显著的特点就是乔治的大脑袋,真的不小,据说他量过他的脑袋,周长有63公分(25英寸),比常人多出约18%,假设他的脑袋跟其他人一样长,那么他的脑容量比常人就大上38%。 脑袋大是人类的特点,当胎儿在子宫中发育时,大多数的营养就给大脑袋吸收去了,生产的时候,人类就倍感艰难,产妇要历经数小时才把大脑袋分娩出来,脑袋出来了,就意味着痛苦结束,没出来,就威胁大人胎儿生命。大脑袋是人类的标志。 如果你学画画,在学习人物素描时,脑袋就成了通常计量标准,这源于达芬奇,他把解剖学的计量研究带入了艺术世界。在其经典的素描指南中,人的理想身体比例是8个头长,当然,那是成年人。人出生后在1岁时头长大约15公分,身高约4个头长;到5岁时,头长增长为18公分,身高约6个头长;到16岁时,画家就估计人头长23公分,身高7.5个头长。 分不清楚现实与虚拟的作者会告诉你人达不到理想头长,一般就只有16岁时的比例,而英雄人物才能达到9个头长 1 。那是一知半解的结果,因为视角的缘故,画家增大了头在素描中的比例,这取决于简单的光学原理,头是人物活动的聚焦点,因此,头总会被显得比实际要大。在16岁时,意大利人中男性头长约19公分,女性18公分,男性有9个头长,女性有8.7个头长 2 。在20岁时,印度古吉那特邦人男性头长18公分,女性17公分,而身高分别有9.5及9.1个头长 3 。在近100多年前,学者就测到俄罗斯人、吉尔吉斯人、乌兹别克人、及亚美尼亚人身高为大约9个头长。身高并不跟头长成正比,俄罗斯人最高,但较矮的亚美尼亚人比他们多出几乎半个头长 4 。 图一、聚焦头部产生的假相 对于科学而言,我们可以凭借指纹、牙齿、乃至于微量的细胞成份来判断一个人的身份。但自有史以来,我们就是头,当你拿出身份证、护照、或者驾照等身份证明文件来,看到的只有头,其它身体部件不见踪影,也没有关系。人的头在成年时期仍然继续生长,当然,变化并不太大,往往是成年人在几十年后发现自己的帽子变小了 5 ,不过,由于老年后身高会下降,头的重要性还会继续增加。 为什么头那么重要呢?因为它是人类智慧的物质基础。大脑袋就等于高智慧生物。一个自然而然的问题就是乔治*罗泊斯的大脑袋是否跟智商有关系。一问这个问题,我们就踏入了科学的禁区,一个让人敏感的话题,那就是脑容量的种族差异以及它跟智商的关系。科学家会因为研究这个问题而被贴上种族主义的标签,研究成果也会因为这一标签而被压制批评。 一般而言,身高黑种人比白人要高,而白人比东方亚洲人要高,但从脑容量上说,则相反,黑种人最低,白种人比黑种人要多不少,而亚洲人更高。这样的研究的确给种族主义提供了素材,但是,欧洲人在100多年前同样地瞧不起亚洲人,并不妨碍他们报道亚洲人有比他们更高的脑容量。 通过近一个世纪的研究,大量的学术报告证实了人种之间的脑容量的差别。通过尸体解剖,科学家发现白种人大脑比黑人的重约100克,而亚洲人更重。在1984年,科学家报导测量多达两万个颅骨,亚洲人比白种多了近50毫升的脑容量,而白种人比黑种人又多了超过80毫升的脑容量。在1990年代,通过对数万成人或者小孩的脑测量,也相继证实上述区别在活人就存在,并且黑人个子比白人高,其脑容量仍然低于白人,亚洲人个子矮,但脑容量仍然高于白人。在1994年,有报道用现代工具核磁共振(MRI)直接测量脑容量,证实黑人比白人更低。 图二、三人种脑容量比较(来源:鲁希顿《人种、进化、与行为》 6 ) 在出生后,人类的大脑增长远超过其它有脑动物,出生时我们的脑容量只有成年时的30%,大猩猩是60%,猴子是100%。这是为什么人类发育时间相对较长,而儿童时期营养与环境又是那么重要。脑容量跟人类智商有直接的关系,智商跟MRI测量的脑容量的相关系数是0.44,跟脑周长的相关系数是0.20,而用其它方式测得的脑容量,则变化于0.24-0.41,也就是说,现有的研究表明大脑袋更聪明。 大脑袋的遗传率超过80%,估计一半会传递给智商,使智力的遗传效率达到50%。因此,智商也有种族差异。黑种人的智商平均为85,白人为100,而亚洲人为106,与脑容量的区别大致相当。证明大脑袋的优势的最好研究是收养小孩的智商研究,因为收养家庭就让小孩的生长环境得到了最好的控制。在白人收养的小孩中,智商以亚洲人最高,白人次之,黑白混血儿再次,黑人最低。美国中产阶级白人收养黑人小孩成长后智商高于非收养黑人,以及美国黑人显著高于非洲黑人,表明后天环境的重要性。 图三、人种之间的智商差异(源:鲁希顿《人种、进化、与行为》 6 ) 伦敦大学双博士鲁希顿(P. Rushton)在其《人种、进化、与行为》一书中解释人种脑袋大小智商高低的进化意义 6 。当我们的祖先走出非洲时,他们移居到四季分明的温带或者环境艰苦的亚寒带地区,我们的身体更适于在炎热的非洲生活,食物一年四季都不缺乏,走出非洲的人需要更多的创造性与智力来解决环境的挑战,比如如何为缺乏食物的季节规划、制造更多的工具、衣物、住处、以及使用火就使得我们的大脑更为发达,或者说存在一个系统的针对大脑袋高智商的筛选过程。 当画家作画的时候,或者是人类在观察其他人的时候,我们潜意识里的大脑袋选择本能就发挥了作用,我们只登记观察对象的脑袋,就象照相时聚焦始终会选择脑袋一样,尽管身体其它部位的特征具有同样的鉴别性,我们也会忽略之。那么,是不是脑袋越大的人越受欢迎呢?小孩脑袋相对较大,那是一种特殊的喜爱,我们是否在成年人中也喜爱大脑袋呢? 在2008年,来自英国的学者赖尼等人针对这个问题进行了研究 7 。他们制造了10幅标准人体图片,从6头身到10头身,看观察者更喜欢哪种体型。其中最受欢迎的是7.5头身,8头身次之。如果用超过10%的喜爱程度的图取均值,则为7.8头身。也就是说,艺术家们采用的一般8头身标准低估了人们对大脑袋的喜爱程度。 图四、赖尼等人使用的6头、7.5头、及10头身影像(源:赖尼等2008 7 ) 为什么人们不喜欢更大的脑袋呢?比如6头身。乔治*罗泊斯的确有一个漂亮的太太,但该剧中他总是扮演一个失意大头的形象。在人的发育中,大脑是属于优先供应的器官,不过,它的大小相对衡定,头长又比头宽头高更衡定,头长相对于身高的比例往往更多地取决于身高,而身高又取决于营养与健康状态,营养不良的身高发育受限,如果个儿长得太高,又可能是肢端肥大症,因此,我们潜意识里更喜欢相对适中却又显得大一些的脑袋。 美的基础是健康,大的脑袋装智慧。 注: 1 见方舟子《人们为什么爱美腿》: “达•芬奇画过一幅著名的人体比例图,代表着西方传统美术对标准人体的看法,作为人体绘画、雕塑的参考。比如,一个人的身高等于8个头长。这只是“凡人”的标准。在西方传统美术中,如果画到神或英雄人物,身高往往就画成了8.5个头长,以显得威武、高贵。多出来的身体高度,相当一部分来自把腿拉长。而在美国漫画中,英雄人物的身高更为夸张,能达到9个头、15个头甚至20个头那么高。” “即使是8头身也只是理想化的人体,在实际上很少有人能达到这个标准。一般人的身高通常只等于7.5个头长。影响身高的主要是腿长。换句话说,一般人的腿长都没有达到“标准”,至少是西方传统美学的标准。” 2 根据两份意大利人体测量调查推算。身高见Aldegheri, R. and Agostini, S., A Chart of Anthropometric Values J Bone Joint Surg 1993; 75-B: 86-88; 头长见Sanna, E. et al. Growth charts of head length and breadth for regional areas? A study in Sardinia (Italy). HOMO - Journal of Comparative Human Biology 2012; 63: 67– 75 3 Jadav, H.R. and Shah, G.V. Determination of personal height from the length of head in Gujarat Region. J.Anat.Soc.India 2004; 53(1): 20-21 4 Hrdlicka, A. Growth during Adult Life. Proceedings of the American Philosophical Society, 1936; 76(6): 847-897 5 Krdlicka A. Growth of the Head during Adult Life: Further Evidence. Amer J of Physical Anthropology 1938; 24(2): 127-159 6 Rashton, J.P. Race, Evolution, and Behavior: A Life History Perspective. 2nd Special Abridged Edition. 2000; The Charles Darwin Research Institute, Port Huron, MI 7 Naini, F.B. et al. The influence of craniofacial to standing height proportion on perceived attractiveness. Int. J. Oral Maxillofac. Surg. 2008; 37: 877–885
F ree will and the brain 自由意志与大脑 Self interest 自我意识与自我利益 Where there’s a will there’s a way 有志者事竟成 Dec 17th 2011 | from the print edition ONE paradox has come under scrutiny since medical imaging of the brain became common in the 1980s. This is the apparent clash between the mechanical nature of the mind and the impression that people can will their own thoughts and actions. Michael Gazzaniga, a neuroscientist at the University of California, Santa Barbara, believes that “we are personally responsible agents and are to be held accountable for our actions, even though we live in a determined universe.” 自从脑部医学成像技术在上个世纪八十年代普及开来之后,人们也开始对一个矛盾现象进行深入推敲。显然,这里说的是人脑的机械本质与人可以随意控制自己的想法和行为这种自身感觉之间的矛盾。圣巴巴拉市加利福尼亚大学的神经科学家迈克尔·葛詹尼加认为“尽管我们生活在一个已经设定好规则的世界当中,但是我们每个人都是自己的责任代理人并且应该对自己的一切行为负责。” The idea that the mind exists separately from the body has a long history; Descartes invoked it during the 17th century. But in recent years opinion has shifted somewhat behind the notion that people are constrained by their physical embodiment. Individuals are suspected of being predisposed to eat compulsively or drink excessively, and various other characteristics are thought to have a genetic basis. Mr Gazzaniga reckons that, while such studies are useful, they give an incomplete picture of the true nature of humanity. 人的思维与身体是各自独立的存在这一理论具有相当悠久的历史,它由笛卡尔在17世纪提出。近些年人们对这一观点发生了的看法发生了转变,开始认同人们的思维是被束缚在了肉身中这一观念。许多学者怀疑人类个体倾向于强迫性地进食或过度饮水,并指出人类其他的多种多样的个性特征则是基于遗传基础。葛詹尼加则认为,这些研究固然有用,但并没有揭开人类真实本质的全貌。 In his new book Mr Gazzaniga uses animal studies to argue that the brain is shaped by the tasks before it, pointing out that the brains of New World carnivorous bats are more similar to those of Old World carnivorous bats than they are to New World fruit bats, despite these being their closer cousins. But his logic is shaky. He also cautions against applying information gleaned from studying the structure and function of chimpanzee brains to the human realm. Mr Gazzaniga appeals, not wholly convincingly, to quantum mechanics and complexity to provide escape routes from the conclusion that, because the body is a biochemical system, what happens in the mind is physically determined. 葛詹尼加在新书中运用动物实验来论证大脑(的进化发展)是由它面对的任务决定的。他举出的例子是,美洲新大陆食肉蝙蝠与欧洲食肉蝙蝠之间的相似程度超过了它们与近亲美洲新大陆果蝠的相似程度。但他这个逻辑显然不太站得住脚。(因为)他还反对将研究黑猩猩的大脑结构和功能收集到的理论在人体上对号入座。 虽然影响力有限, 但葛詹尼加先生仍呼吁量子力学和复杂性科学能够提供依据, 将研究者们从这样的囹圄中解救出来,那就是 :人体是一个生物化学系统,人的所有思维活动都是由身体决定的。 He is on stronger ground with his claim that people can be utterly unaware of what is happening inside their heads, outlining how his patients provide post-hoc “explanations” for their actions. He describes a patient whose moral reasoning has been disrupted by surgery to separate the hemispheres, who then judges that it is acceptable for a waitress to serve sesame seeds to someone she thinks is allergic to them, but who is not. As soon as the side of his brain that did not make the judgment hears what he has just said, the patient tries to offer an explanation: he blurts out that sesame seeds are tiny and cannot hurt anyone. 通过介绍和说明他的病人人是如何为自己的行为给出因果"解释"的,葛詹尼加提出,人们对自己的脑子所经历的改变根本浑然不觉,他的这一理论得到了颇为广泛的认同。他描述了这样一个病人,其道德推理系统已经在医生对其进行分开两个大脑半球的手术时破坏,此后,这个病人认为一个服务员把芝麻送给那些对芝麻不过敏但是服务员认为他们会对芝麻过敏的人这种做法是可以接受的。 就在他的判断力所在的脑半球并不能接收到他刚刚所说的讯息的同时, 他努力对自己刚刚的反应提供一个解释:他不假思索的说道,芝麻太小了,所以根本不能伤害到任何人。 In an attempt to resolve the paradox, Mr Gazzaniga locates the origin of personal responsibility outside the brain, as a consequence of a social contract between two or more individuals. In so doing, he neatly but unconvincingly removes the physical basis for good or bad behaviour. “Who’s in Charge?” is a wide-ranging and enjoyable exploration of how science interrogates the mind. Luckily for readers who enjoy grappling with issues such as the origin of thought, and whether people are free to will what they want, it leaves plenty more to be written on the subject. 为了解开文章开头提到的矛盾,葛詹尼加将个体的责任感独立于大脑之外,作为人类社会中两个甚至更多个体之间的存在社会契约的结果。这么做的话,葛詹尼加就巧妙地将人类好坏行为的生理基础去掉了,但说服力还是不够。”谁做主?“——这是人们在探究科学如何盘问人心的过程中广泛运用且乐在其中的一个命题。喜欢探寻诸如思维的来源的读者们是幸运的,人类是否应该予取予求这样的论题确实为科学家们提供了巨大的发挥空间。 from the print edition | United States 译者:郑恒 原文出自《经济学人》杂志 译者注: 迈克尔·葛詹尼加(Michael Gazzaniga)是全球著名的脑科学家之一,被誉为“认知神经科学之父”,早年本科毕业于达特茅斯学院,其后进入加利福尼亚理工学院,师从因对人类“裂脑”现象的研究而获诺贝尔奖的Roger Sperry,获生物心理学博士学位。 通过对裂脑人所进行的大量研究,Michael Gazzaniga大大促进了我们对人类大脑功能偏侧性以及大脑两半球之间关系的认识。他不仅在临床以及基础科学研究的圈子内闻名遐尔,而且对外行的社会公众来说也是声名远扬。1985年,他出版了《社会性大脑:发现心智的网络》(The Social Brain: Discovering the Networks of the Mind)一书,对大脑功能偏侧性的特征以及大脑两半球之间的关系进行了研究,成果丰硕;1988年,他出版了《心智问题》(Mind Matters)一书,成为心智紊乱问题研究的入门作品;1992年,他出版了《自然界的心智:思维、情绪、性别、语言以及智能的生物学根源》(Nature’s Mind: The Biological Roots of Thinking, Emotions, Sexuality, Language, and Intelligence),纽约时报评价说:“对脑科学研究来说,此书所做的研究堪比斯蒂芬·霍金的研究之于宇宙论”;1995年,Michael Gazzaniga通过麻省理工学院出版社出版了里程碑式的着作《认知神经科学》(The Cognitive Neurosciences),对九十多位科学家的工作进行了系统总结,被誉为认知神经科学领域的资料库,目前已经出至第三版;2005年,他又出版了《伦理性的大脑》(The Ethical Brain)一书,对大脑发展与人类伦理形成的关系进行了开创性的探索。 Who's in Charge? : Free Will and the Science of the Brain Michael S. Gazzaniga 34 篇评论 http://books.google.com.hk/books/about/Who_s_in_Charge.html?hl=zh-CNid=1YmsRMe2pZwC HarperCollins , 2011-11-15 - 272 页 pThe father of cognitive neuroscience and author of "Human" offers a provocative argument against the common belief that our lives are wholly determined by physical processes and we are therefore not responsible for our actions pA powerful orthodoxy in the study of the brain has taken hold in recent years: Since physical laws govern the physical world and our own brains are part of that world, physical laws therefore govern our behavior and even our conscious selves. Free will is meaningless, goes the mantra; we live in a "determined" world. pNot so, argues the renowned neuroscientist Michael S. Gazzaniga in this thoughtful, provocative book based on his Gifford Lectures----one of the foremost lecture series in the world dealing with religion, science, and philosophy. "Who's in Charge?" proposes that the mind, which is somehow generated by the physical processes of the brain, "constrains" the brain just as cars are constrained by the traffic they create. Writing with what Steven Pinker has called "his trademark wit and lack of pretension," Gazzaniga shows how determinism immeasurably weakens our views of human responsibility; it allows a murderer to argue, in effect, "It wasn't me who did it----it was my brain." Gazzaniga convincingly argues that even given the latest insights into the physical mechanisms of the mind, there is an undeniable human reality: "We are responsible agents who should be held accountable for our actions, because responsibility is found in how people interact, not in brains." p An extraordinary book that ranges across neuroscience, psychology, ethics, and the law with a light touch but profound implications, "Who's in Charge?" is a lasting contribution from one of the leading thinkers of our time.
长期以来,体温和庞大的脑组织作为哺乳动物、鸟类等高等动物的独特特征,其相互之间的关系一直不是很清楚。 我们最近的实验和理论研究表明,体温的出现,使得脑皮层神经元在动作电位的能量消耗效率方面有数倍的提高。 这意味着,产生一个动作电位,在体温37度状态,要比在室温(16-18摄氏度)情况,节省至少3-4倍的能量。 这从一个侧面说明,体温是优化大脑脑电信号能量效率的一个非常有效的机制。 详细请见: http://www.ploscompbiol.org/article/info%3Adoi%2F10.1371%2Fjournal.pcbi.1002456 Warm Body Temperature Facilitates Energy Efficient Cortical Action Potentials The energy efficiency of neural signal transmission is important not only as a limiting factor in brain architecture, but it also influences the interpretation of functional brain imaging signals. Action potential generation in mammalian, versus invertebrate, axons is remarkably energy efficient. Here we demonstrate that this increase in energy efficiency is due largely to a warmer body temperature. Increases in temperature result in an exponential increase in energy efficiency for single action potentials by increasing the rate of Na + channel inactivation, resulting in a marked reduction in overlap of the inward Na + , and outward K + , currents and a shortening of action potential duration. This increase in single spike efficiency is, however, counterbalanced by a temperature-dependent decrease in the amplitude and duration of the spike afterhyperpolarization, resulting in a nonlinear increase in the spike firing rate, particularly at temperatures above approximately 35°C. Interestingly, the total energy cost, as measured by the multiplication of total Na + entry per spike and average firing rate in response to a constant input, reaches a global minimum between 37–42°C. Our results indicate that increases in temperature result in an unexpected increase in energy efficiency, especially near normal body temperature, thus allowing the brain to utilize an energy efficient neural code. Yuguo Yu 1 , 2 , Adam P. Hill 1 , David A. McCormick 1 * 1 Department of Neurobiology and Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, Connecticut, United States of America, 2 Center for Computational Systems Biology, Fudan University, Shanghai, People's Republic of China Author Summary Conserving energy is essential to life. The brain, while only 2% of the body mass, uses an astounding 20% of its energy. It has long been assumed that this large energy consumption was due to the need to generate the electrical signals through which brain cells communicate: the action potentials. However, recent results reveal that the wires of the mammalian brain – the axons – are remarkably energy efficient. How is this energy efficiency obtained? Here we addressed this question by performing recordings and computational models of mammalian brain cells. We found that the increase in body temperature associated with the evolution of warm-blooded animals had an energetic benefit. The action potentials of warm-blooded animals became remarkably energy efficient, owing simply to the increase in body temperature. These results indicate that mammalian brains, although requiring a great deal of energy to operate, are actually more efficient than expected.
刚看到这样一张图片,如果你只盯着这些随时间变化,颜色发生变化的淡紫色原点,你就会发现只有一种颜色--淡紫色。 如果,你盯着位于中心的"+"看,你就看到原来淡紫色的点会有一些变成绿色。 如果,你长时间的盯着中心的"+"看,你就会发现,淡紫色的原点都消失了,就剩下一个绿色的点在旋转。 视觉和人的大脑真是相当的玄幻,难道这就是Penny所说的“It is not what it looks like”么?
研究绘制人一生大脑基因表达谱 http://www.nature.com/nature/journal/v478/n7370/abs/nature10524.html 来自NIH认知与精神病研究组,Illuminato生物技术公司等处的研究人员发表了题为“Temporal dynamics and genetic control of transcription in the human prefrontal cortex”的文章,发现在人的整个一生当中,大脑的工作和功能虽然几乎不变,但是其基因表达却发生了变化,这将有助于深入分析大脑失序疾病,比如精神分裂症和自闭症等。这一研究成果公布在《自然》( Nature )杂志上。 早在19世纪,科学家就意识到大脑是一个精细的结构,如果能了解了整个大脑的基因活性,科学家就有可能更精确地将大脑解剖学、遗传学和相关疾病联系起来研究,意义十分重大。2003年,有科学家寻求利用微阵列技术测定小鼠大脑基因活性,但至今对于人整个一生当中,大脑基因表达的情况,科学家们还并不清楚。 在这篇文章中,研究人员利用一些基因组分析技术,完成了来自大脑前额叶皮层的全基因组范围遗传学(DNA),和基因表达(RNA)分析,这269份样品涉及了人类整个生命周期中的不同阶段。 研究人员发现在不同的生命时期,基因行为有很大变化,而且其中有个特殊时期:胎儿期的大脑在基因活动上发生了巨大的变化,许多之前表达大量mRNA的基因,在出生后就突然的下降了,这在胎儿期变化比其它任何时间都要快。 在Nature的另外一篇文章中,耶鲁大学的研究人员分析了57个大脑不同基因的mRNA水平,这两份研究结果都表明许多在出生后表达下降的基因,到老年期又活动激增,其中最大的变化发生在胎儿期,然后下降直到中年期,在50-70岁时表达从新变得相当高。 这些研究都有助于解析大脑是如何成长和衰老的,也有助于深入分析大脑失序疾病,比如精神分裂症和自闭症等。(来源:生物通 万纹) Temporal dynamics and genetic control of transcription in the human prefrontal cortex renchunxiao 添加于 2011-11-4 15:23:07 97次阅读 | 0次推荐 | 0个评论 Previous investigations have combined transcriptional and genetic analyses in human cell lines1, 2, 3, but few have applied these techniques to human neural tissue4, 5, 6, 7, 8. To gain a global molecular perspective on the role of the human genome in cortical development, function and ageing, we explore the temporal dynamics and genetic control of transcription in human prefrontal cortex in an extensive series of post-mortem brains from fetal development through ageing. We discover a wave of gene expression changes occurring during fetal development which are reversed in early postnatal life. One half-century later in life, this pattern of reversals is mirrored in ageing and in neurodegeneration. Although we identify thousands of robust associations of individual genetic polymorphisms with gene expression, we also demonstrate that there is no association between the total extent of genetic differences between subjects and the global similarity of their transcriptional profiles. Hence, the human genome produces a consistent molecular architecture in the prefrontal cortex, despite millions of genetic differences across individuals and races. To enable further discovery, this entire data set is freely available (from Gene Expression Omnibus: accession GSE30272; and dbGaP: accession phs000417.v1.p1) and can also be interrogated via a biologist-friendly stand-alone application (http://www.libd.org/braincloud). 作 者: Carlo Colantuoni; Barbara K. Lipska; Tianzhang Ye; Thomas M. Hyde; Ran Tao; Jeffrey T. Leek; Elizabeth A. Colantuoni; Abdel G. Elkahloun; Mary M. Herman; Daniel R. Weinberger; Joel E. Kleinman 期刊名称: Nature 期卷页: 2011-10-26 第478卷 第7370期 519~523页 学科领域: 生命科学 遗传学与生物信息学 人类遗传学 添加人是否为作者: 否 原文链接: http://www.nature.com/nature/journal/v478/n7370/abs/nature10524.html DOI: doi:10.1038/nature10524 ISBN: 0028-0836 关键词: Genetics and genomics, Neuroscience, Developmental biology, Genetics and genomics
《自然神经科学》:大脑杏仁体大小可反映人的社交情况 http://news.sciencenet.cn/htmlnews/2010/12/242015.shtm How a Facebook feature in the brain rules your social network http://www.dailymail.co.uk/news/article-1341689/Size-does-matter-Party-animals-great-social-lives-lots-friends-bigger-Facebook-feature-brain.html http://arrowsmith.psych.uic.edu/cgi-bin/arrowsmith_uic/edit_b.cgi Start A-Literature C-Literature B-list Filter Literature A-query: social network C-query: temporal lobe and brain The B-list contains title words and phrases (terms) that appeared in both the A and the C literature. 536 articles appeared in both literatures and were not included in the process of computing the B-list but can be viewed here . The results of this search are saved under id # 26164 and can be accessed from the start page after you leave this session. There are 1012 terms on the current B-list ( 284 are predicted to be relevant), which is shown ranked according to predicted relevance. The list can be further trimmed down using the filters listed in the left margin. To assess whether there appears to be a biologically significant relationship between the AB and BC literatures for specific B-terms, please select one or more B-terms and then click the button to view the corresponding AB and BC literatures. Use Ctrl to select multiple B-terms. job id # 26164 started Mon Dec 27 03:08:52 2010 Max_citations: 50000 Stoplist: /var/www/html/arrowsmith_uic/data/stopwords_pubmed Ngram_max: 3 26164 Search ARROWSMITH A A_query_raw: social networkMon Dec 27 03:53:41 2010 A query = social network started Mon Dec 27 03:53:41 2010 A query resulted in 50000 titles 26164 Search ARROWSMITH C C_query_raw: temporal lobe and brain Mon Dec 27 03:53:59 2010 C: temporal lobe and brain 35838 A: pubmed_query_A 180694 AC: ( social network ) AND ( temporal lobe and brain ) 536 C query = temporal lobe and brain started Mon Dec 27 03:54:01 2010 C query resulted in 35838 titles A AND C query resulted in 536 titles 23165 B-terms ready on Mon Dec 27 04:00:11 2010 Sem_filter: Genes Molecular Sequences, and Gene Protein Names 1012 B-terms left after filter executed Mon Dec 27 04:24:19 2010 B-list on Mon Dec 27 04:26:15 2010 1 serotonin transporter gene 2 reelin 3 transporter gene 4 5-ht1a 5 erp 6 cannabinoid receptor 7 bdnf 8 promoter polymorphism 9 ptsd 10 p300 11 dopamine transporter gene 12 meg 13 apoe 14 epsilon4 allele 15 cb1 16 immediate early gene 17 velocardiofacial syndrome 18 parvalbumin 19 dsm 20 body mass index 21 neurotrophin 22 ca1 23 neuregulin 24 seizure severity 25 apolipoprotein e 26 5-ht2a 27 single nucleotide polymorphism 28 doublecortin 29 c jun n 30 dat1 31 fmr1 32 comt 33 cox-2 34 abeta 35 mthfr 36 drd4 37 spatial learning 38 gabaa 39 mecp2 40 epileptiform 41 ftd 42 contextual fear conditioning 43 adhd 44 presenilin 45 dopamine d2 receptor 46 genome wide 47 nr2b 48 estrogen receptor alpha 49 glutamate receptor 50 apoe epsilon4 allele 51 g72 52 gaba a receptor 53 drd2 54 bdnf gene 55 quantitative trait locus 56 scn1a 57 vntr 58 5ht1a 59 calbindin 60 spike wave 61 disc1 62 akt 63 leptin 64 statin 65 dysbindin 66 trkb 67 creb 68 clock gene 69 synapsin 70 erk1 71 gdnf 72 body mass 73 gad65 74 candidate gene 75 c jun 76 vasopressin gene 77 apolipoprotein e allele 78 caspase-3 79 masking 80 zenk 81 gaba a 82 laterality 83 prion protein 84 c fos 85 estrogen receptor beta 86 pup 87 matrix metalloproteinase 88 5-ht2a receptor gene 89 stathmin 90 promoter methylation 91 opioid receptor 92 brain volume 93 leptin receptor 94 fosb 95 aromatase 96 ubiquitin 97 mtor 98 olfactory pathway 99 motor neuron disease 100 ect 101 mri 102 reeler 103 mglur5 104 glur1 105 cit 106 5ht2a 107 e selectin 108 gene family 109 pet 110 cd14 111 mmpi 112 hiv 113 tsc1 114 tms 115 twin 116 pten 117 epilepsy 118 er beta 119 p38 120 dopamine receptor 121 neuropeptide y 122 strs 123 aquaporin 124 ampa 125 ssri 126 fgf 127 mrs 128 abcb1 129 theta 130 cdna 131 glioma 132 schizophrenia risk gene 133 urocortin 134 gene variant 135 early growth response 136 signal regulated kinase 137 psa 138 transgene 139 kdr 140 egr3 141 mst 142 transporter 143 il-6 144 differentially expressed gene 145 cleft lip 146 y2 147 spinocerebellar ataxia 148 gaba 149 tactile 150 race 151 maze 152 ghrelin 153 huntington disease 154 promoter region 155 corticotropin releasing hormone 156 tachykinin 157 tau 158 gfap 159 pcna 160 genomic imprinting 161 sry 162 gene promoter 163 war 164 startle response 165 gene brain 166 nr1 167 triplet repeat 168 cue 169 wnt7a 170 ethanol consumption 171 comt gene 172 emotionality 173 5-ht 174 p3 175 fgf17 176 olfactory 177 calmodulin 178 activin 179 diabetes 180 gnrh 181 alzheimer disease 182 igf i 183 anxiety 184 rgs4 185 rey 186 nmdar 187 glast 188 cpap 189 microrna 190 glucocorticoid receptor 191 amyotrophic lateral sclerosis 192 gonadotropin releasing hormone 193 5-ht6 194 gd 195 nr3a 196 catechol o-methyltransferase 197 fos 198 snap-25 199 g30 gene 200 tic 201 crf 202 igf 203 fgf receptor 204 pick 205 exon 206 erbb4 207 mao 208 cytokine gene 209 snca 210 bat 211 vitamin d receptor 212 eat 213 dcm 214 dna pkcs 215 spike 216 obesity 217 lobe 218 smile 219 rem 220 sib 221 oxytocin 222 lip 223 gene encoding 224 short form 225 cadherin 226 pomc 227 estrogen receptor 228 progesterone receptor 229 ngf 230 cell adhesion molecule 231 nf kappab 232 trait 233 connexin 234 neuropeptide 235 fibroblast growth factor 236 bee 237 rearing 238 essential tremor 239 hypercholesterolemia 240 parkinson disease 241 aura 242 seizure susceptibility 243 prostate cancer 244 huntington 245 hydrocephalus 246 mela 247 npy 248 spastic paraplegia 249 caveolin-1 250 il-1beta 251 tnf alpha 252 celiac disease 253 rank 254 ego 255 d3 receptor 256 angiotensin receptor 257 oscillator 258 meta 259 dna binding 260 dopamine receptor gene 261 grin2a 262 cjd 263 map 264 anorexia 265 fear 266 p53 267 trail 268 il-1 269 tia 270 raby 271 analysis gene 272 androgen receptor 273 aminotransferase 274 fm 275 grasp 276 mrl 277 clock 278 par-4 279 ip3r 280 hyperparathyroidism 281 neurotensin 282 receptor gene 283 mglur2 284 polycystic ovary syndrome http://arrowsmith.psych.uic.edu/cgi-bin/arrowsmith_uic/show_sentences.cgi Start A-Literature C-Literature B-list Filter Literature AB literature B-term BC literature social network erp temporal lobe and brain 1: A truth that's told with bad intent: an ERP study of deception.2010 Add to clipboard 2: Impaired top-down processes in schizophrenia: A DCM study of ERPs.2010 Add to clipboard 3: Response to familiar faces, newly familiar faces, and novel faces as assessed by ERPs is intact in adults with autism spectrum disorders.2010 Add to clipboard 4: The influence of the diffusion of responsibility effect on outcome evaluations: Electrophysiological evidence from an ERP study.2010 Add to clipboard 5: Effects of role typicality on processing person information in German: Evidence from an ERP study.2010 Add to clipboard 6: ERPs on a Continuous Performance Task and Self-Reported Psychopathic Traits: P3 and CNV Augmentation are Associated with Fearless Dominance.2010 Add to clipboard 7: Evidence for modulation of facial emotional processing bias during emotional expression decoding by serotonergic and noradrenergic antidepressants: an event-related potential (ERP) study.2009 Add to clipboard 8: Knowing when to trust others: an ERP study of decision making after receiving information from unknown people.2009 Add to clipboard 9: ERP correlates of effortful control in children with varying levels of ADHD symptoms.2009 Add to clipboard 10: ERP time course and brain areas of spontaneous and intentional goal inferences.2009 Add to clipboard 11: Trait inferences in goal-directed behavior: ERP timing and localization under spontaneous and intentional processing.2009 Add to clipboard 12: RP and N400 ERP components reflect semantic violations in visual processing of human actions.2009 Add to clipboard 13: Phased processing of facial emotion: an ERP study.2009 Add to clipboard 14: Effects of quetiapine on cognitive functions in schizophrenic patients: a preliminary single-trial ERP analysis.2009 Add to clipboard 15: Emotional MMN: Anxiety and heart rate correlate with the ERP signature for auditory change detection.2009 Add to clipboard 16: Sentence integration processes: An ERP study of Chinese sentence comprehension with relative clauses.2009 Add to clipboard 17: When people matter more than money: an ERPs study Comparison and competition in the brain.2009 Add to clipboard 18: False belief reasoning in the brain: an ERP study.2008 Add to clipboard 19: Fast responders have blinders on: ERP correlates of response inhibition in competition.2008 Add to clipboard 20: Atypical processing of fearful face-voice pairs in Pervasive Developmental Disorder: an ERP study.2008 Add to clipboard 21: The age of the beholder: ERP evidence of an own-age bias in face memory.2008 Add to clipboard 22: Augmenting serotonin neurotransmission with citalopram modulates emotional expression decoding but not structural encoding of moderate intensity sad facial emotional stimuli: an event-related potential (ERP) investigation.2008 Add to clipboard 23: Links between rapid ERP responses to fearful faces and conscious awareness.2008 Add to clipboard 24: When eye creates the contact! ERP evidence for early dissociation between direct and averted gaze motion processing.2007 Add to clipboard 25: Electrophysiological correlates of word repetition spacing: ERP and induced band power old/new effects with massed and spaced repetitions.2007 Add to clipboard 26: Heterogeneity in the patterns of neural abnormality in autistic spectrum disorders: evidence from ERP and MRI.2007 Add to clipboard 27: The effects of eye and face inversion on the early stages of gaze direction perception--an ERP study.2007 Add to clipboard 28: Rapid detection of fear in body expressions, an ERP study.2007 Add to clipboard 1: Spectra-temporal patterns underlying mental addition: an ERP and ERD/ERS study.2010 Add to clipboard 2: Event-related potential and functional MRI measures of face-selectivity are highly correlated: A simultaneous ERP- fMRI investigation.2010 Add to clipboard 3: Line by line: the ERP correlates of stroke order priming in letters.2010 Add to clipboard 4: Temporal precedence of emotion over attention modulations in the lateral amygdala: Intracranial ERP evidence from a patient with temporal lobe epilepsy.2010 Add to clipboard 5: Maturation of auditory temporal integration and inhibition assessed with event-related potentials (ERPs).2010 Add to clipboard 6: Why is the N170 enhanced for inverted faces? An ERP competition experiment.2010 Add to clipboard 7: .2010 Add to clipboard 8: ERP measures of partial semantic knowledge: left temporal indices of skill differences and lexical quality.2009 Add to clipboard 9: Foreword to the special issue. Before the N400: Early Latency Language ERPs.2009 Add to clipboard 10: Early adaptation to repeated unfamiliar faces across viewpoint changes in the right hemisphere: evidence from the N170 ERP component.2009 Add to clipboard 11: Tuning of the visual word processing system: distinct developmental ERP and fMRI effects.2009 Add to clipboard 12: Neural correlates of affective picture processing--a depth ERP study.2009 Add to clipboard 13: Cortical auditory processing in preterm newborns: an ERP study.2009 Add to clipboard 14: High-resolution ERP mapping of cortical activation related to implicit object-location memory.2009 Add to clipboard 15: The time course of temporal discrimination: An ERP study.2009 Add to clipboard 16: Hemispatial PCA dissociates temporal from parietal ERP generator patterns: CSD components in healthy adults and depressed patients during a dichotic oddball task.2008 Add to clipboard 17: Feedback-based error monitoring processes during musical performance: an ERP study.2008 Add to clipboard 18: Combining ERP and structural MRI information in first episode schizophrenia and bipolar disorder.2008 Add to clipboard 19: Gender-specific development of auditory information processing in children: an ERP study.2008 Add to clipboard 20: FMRI /ERP of musical syntax: comparison of melodies and unstructured note sequences.2008 Add to clipboard 21: Spatiotemporal dynamics of single-letter reading: a combined ERP- FMRI study.2008 Add to clipboard 22: Evidence for automatic sentence priming in the fusiform semantic area: convergent ERP and fMRI findings.2008 Add to clipboard 23: The time-frequency representation of the ERPs of face processing.2008 Add to clipboard 24: From amnesia to dementia: ERP studies of memory and language.2007 Add to clipboard 25: The associative processes involved in faces-proper names versus animals-common names binding: a comparative ERP study.2007 Add to clipboard 26: ERP assessment of functional status in the temporal lobe: examining spatiotemporal correlates of object recognition.2007 Add to clipboard 27: ERP effects of meaningful and non-meaningful sound processing in anterior temporal patients.2007 Add to clipboard 28: Frontal and posterior ERPs related to line bisection.2007 Add to clipboard 29: Category specificity in the processing of color-related and form-related words: an ERP study.2006 Add to clipboard 30: Hemodynamic and electrophysiological relationship involved in human face processing: evidence from a combined fMRI -ERP study.2006 Add to clipboard 31: An ERP study of temporal discrimination in rats.2006 Add to clipboard 32: The time course of visual word recognition as revealed by linear regression analysis of ERP data.2006 Add to clipboard 33: Hippocampus proper distinguishes between identified and unidentified real-life visual objects: an intracranial ERP study.2006 Add to clipboard 34: Absent event-related potential (ERP) word repetition effects in mild Alzheimer's disease.2006 Add to clipboard 35: The categorization of natural scenes: brain attention networks revealed by dense sensor ERPs.2006 Add to clipboard 36: Frontoparietal network involved in successful retrieval from episodic memory. Spatial and temporal analyses using fMRI and ERP. 2006 Add to clipboard 37: The effects of attentional load on auditory ERPs recorded from human cortex.2006 Add to clipboard 38: An ERP investigation of emotional processing in European and Japanese individuals.2006 Add to clipboard 39: Scalp topography and intracerebral sources for ERPs recorded during auditory target detection.2006 Add to clipboard 40: Early stages (P100) of face perception in humans as measured with event-related potentials (ERPs).2005 Add to clipboard 41: ERPs correlates of EEG relative beta training in ADHD children.2005 Add to clipboard 42: Combined event-related fMRI and intracerebral ERP study of an auditory oddball task.2005 Add to clipboard 43: Control mechanisms mediating shifts of attention in auditory and visual space: a spatio-temporal ERP analysis.2005 Add to clipboard 44: 2004 Add to clipboard 45: Superior temporal gyrus and P300 in schizophrenia: a combined ERP/ structural magnetic resonance imaging investigation.2004 Add to clipboard 46: 2004 Add to clipboard 47: From orthography to phonetics: ERP measures of grapheme-to-phoneme conversion mechanisms in reading.2004 Add to clipboard 48: Sensory ERPs predict differences in working memory span and fluid intelligence.2004 Add to clipboard 49: Early amygdala reaction to fear spreading in occipital, temporal, and frontal cortex: a depth electrode ERP study in human.2004 Add to clipboard 50: ERP study of pre-attentive auditory processing in treatment-refractory schizophrenia.2004 Add to clipboard 51: Cortical lateralization during verb generation: a combined ERP and fMRI study.2004 Add to clipboard 52: The facilitated processing of threatening faces: an ERP analysis.2004 Add to clipboard 53: An ERP index of task relevance evaluation of visual stimuli.2004 Add to clipboard 54: Recognition of famous faces in the medial temporal lobe: an invasive ERP study.2004 Add to clipboard 55: Immature cortical responses to auditory stimuli in specific language impairment: evidence from ERPs to rapid tone sequences.2004 Add to clipboard 56: Neural bases of cognitive ERPs: more than phase reset.2004 Add to clipboard 57: A high density ERP comparison of mental rotation and mental size transformation.2003 Add to clipboard 58: The human temporal lobe integrates facial form and motion: evidence from fMRI and ERP studies.2003 Add to clipboard 59: Simultaneous ERP and fMRI of the auditory cortex in a passive oddball paradigm.2003 Add to clipboard 60: An ERP study of the global precedence effect: the role of spatial frequency.2003 Add to clipboard 61: The impact of motor activity on intracerebral ERPs: P3 latency variability in modified auditory odd-ball paradigms involving a motor task.2003 Add to clipboard 62: ERP abnormalities of illusory contour perception in Williams syndrome.2003 Add to clipboard 63: Differentiating amodal familiarity from modality-specific memory processes: an ERP study.2003 Add to clipboard 64: Differential contribution of frontal and temporal cortices to auditory change detection: fMRI and ERP results.2002 Add to clipboard 65: Early involvement of the temporal area in attentional selection of grating orientation: an ERP study.2002 Add to clipboard 66: Error processing--evidence from intracerebral ERP recordings.2002 Add to clipboard 67: Attentional selection in the processing of hierarchical patterns: an ERP study.2001 Add to clipboard 68: Event-related brain potentials (ERPs) in schizophrenia for tonal and phonetic oddball tasks.2001 Add to clipboard 69: Differentiating ERAN and MMN: an ERP study.2001 Add to clipboard 70: Dissociating the neural correlates of item and context memory: an ERP study of face recognition.2001 Add to clipboard 71: Hemispheric asymmetries of visual ERPs in left-handed bilinguals.2001 Add to clipboard 72: A transient dominance of theta ERP component characterizes passive auditory processing: evidence from a developmental study.2001 Add to clipboard 73: An ERP investigation of binding and coreference.2000 Add to clipboard 74: Disturbance of semantic processing in temporal lobe epilepsy demonstrated with scalp ERPs.2000 Add to clipboard 75: Searching for face-specific long latency ERPs: a topographic study of effects associated with mismatching features.1999 Add to clipboard 76: Intracranial ERPs in humans during a lateralized visual oddball task: II. Temporal, parietal, and frontal recordings.1999 Add to clipboard 77: The role of frontal and temporal lobes in visual discrimination task--depth ERP studies.1999 Add to clipboard 78: Brain event-related potentials (ERPs) in schizophrenia during a word recognition memory task.1999 Add to clipboard 79: Effects of prefrontal lesions on lexical processing and repetition priming: an ERP study.1998 Add to clipboard 80: Limbic ERPs predict verbal memory after left-sided hippocampectomy.1998 Add to clipboard 81: Face and shape repetition effects in humans: a spatio-temporal ERP study.1997 Add to clipboard 82: A topographical ERP study of healthy premature 5-year-old children in the auditory and visual modalities.1997 Add to clipboard 83: Is working memory intact in alcoholics? An ERP study.1997 Add to clipboard 84: Differential involvement of the human temporal lobe structures in short- and long-term memory processes assessed by intracranial ERPs.1996 Add to clipboard 85: Selected quantitative EEG (QEEG) and event-related potential (ERP) variables as discriminators for positive and negative schizophrenia.1995 Add to clipboard 86: Effects of temporal versus temporal plus extra-temporal lobe epilepsies on hippocampal ERPs: physiopathological implications for recognition memory studies in humans.1995 Add to clipboard 87: The topography of 4 subtraction ERP- waveforms derived from a 3-tone auditory oddball task in healthy young adults.1995 Add to clipboard 88: ERP amplitude and scalp distribution to target and novel events: effects of temporal order in young, middle-aged and older adults.1994 Add to clipboard 89: Focal abnormalities of P3 ERPs unveiled in patients with cortical lesions and primary progressive aphasia by average reference recordings.1994 Add to clipboard 90: Electrical source analysis of auditory ERPs in medial temporal lobe amnestic syndrome.1993 Add to clipboard 91: The auditory N2 component in schizophrenia: relationship to MRI temporal lobe gray matter and to other ERP abnormalities.1993 Add to clipboard 92: EEG, quantitative EEG, BAEP and ERP in centenarians.1993 Add to clipboard 93: Cortical differences in tonal versus vowel processing as revealed by an ERP component called mismatch negativity (MMN).1993 Add to clipboard 94: Comparison of event related potentials (ERPs) distributions obtained with three reference systems: linked binaural, mean reference, extracephalic.1993 Add to clipboard 95: Grade-related changes in event-related potentials (ERPs) in primary school children: differences between two reading tasks.1992 Add to clipboard 96: Scalp topographies dissociate attentional ERP components during auditory information processing.1991 Add to clipboard 97: ERPs and brain structure: relationships across the adult age span in alcoholics and in a patient with herpes simplex encephalitis.1991 Add to clipboard 98: Applications of bit-mappedcognitivepotentials (ERPs) in clinical neurophysiology--CNV complex in patients with destruction of the dorso-anteromedial bidirectional thalamo-prefrontal pathways.1990 Add to clipboard 99: Developmental changes in ERPs to visual language stimuli.1988 Add to clipboard 100: The development of lateral event-related potentials (ERPs) related to word naming: a four year longitudinal study.1988 Add to clipboard 101: Hemispheric distribution of ERP components and word naming in preschool children.1986 Add to clipboard 102: Pathway and hemispheric differences in the event-related potential (ERP) to monaural stimulation: a comparison of schizophrenic patients with normal controls.1985 Add to clipboard 103: The effects of temporal and event uncertainty in determining the waveforms of the auditory event related potential (ERP) .1976 Add to clipboard
据英国《星期日泰晤士报》报道说,科学家们通过扫描女性性高潮时的脑部变化照片发现,女性性高潮过程涉及逾30个不同脑区,而且在达到高潮的每一阶段,脑部活动都会不同程度增加,不但影响脑内的回馈线路,负责理性思维的脑区也会受影响。女性的性高潮要比男性更加持久更加深入,这给神经系统带来了巨大的负荷,这种过度负荷同样也会使女性的痛楚感觉暂时纾减。 美国新泽西州罗格斯大学脑神经科的Barry Komisaruk教授及其研究小组利用计算机扫描,首次拍摄到女性在进入和达到性高潮时的脑部活动情况。研究中,8名女性躺进功能核磁共振成像扫描仪(fMRI)内,盖上毛毯自慰,仪器每隔两秒就拍下一张脑扫描照。大部分人能在5分钟内达到高潮,一些人则需时20分钟。 参加者以举手示意达到高潮,结果发现,部分女性在一个时间段内多次举手,而且仅相隔数秒,反映女性性高潮时间较长,而且会连续经历多次。女性性高潮大多维持10至15秒,而男性性高潮大概只能持续6秒钟左右。 研究人员下一步计划对男性进行同类的脑部扫描,以研究女性性高潮是否比男性更持久和更深入。 女性受试者躺进功能核磁共振成像扫描仪(fMRI)内,以手示意达到性高潮 Barry Komisaruk教授在仪器前记录脑部扫描影像 性兴奋开始至高潮过程中脑部功能活性变化 ( 来源: 环球网 ) 【博主评论】 众所周知,人类的性功能几乎都或多或少与大脑的神经系统有关,男人在情绪低落的时候,性欲也低下,勃起、射精功能也下降;反之,女性亦然。 美国神经科专家丹尼尔阿门曾经说过:性和爱都源于大脑。在他看来,大脑就是性爱的总司令:我们感受到性爱激情,是因为大脑中特定的神经化学体系,让我们产生了这些情感。大脑中的爱情和性念头是如何产生的?又如何在我们脑中徘徊的呢? 近几年,有关性功能在大脑中的功能定位研究方兴未艾,很多学者开始密切关注这一神秘的研究领域。但由于缺乏有效直观的研究手段,进展尤为缓慢。随着功能核磁共振成像技术(fMRI)的出现,为这一领域的研究打开了方便之门,通过该项技术,我们可以实时观察人类性活动中大脑功能区域的活动变化,从而了解性反应在大脑中的准确定位,换句话说,就是让我们能够分辨出大脑中哪些区域控制高潮,哪些区域控制勃起,哪些区域控制射精。。。 研究这些东西意义何在呢?意义在于,只要我们了解了性功能在大脑中的准确定位,我们就可以对这些功能区域进行细致的研究,寻找大脑控制性活动的内在机理,然后选择合适的调节手段,来调节大脑对性功能的控制,并最终用于性功能障碍的治疗。 男性大脑的大体功能定位 女性大脑的大体功能定位 【参考文献】 Secrets of the Female Orgasm Rutgers lab studies female orgasm through brain imaging Female orgasm 'overwhelms' Revealed: What goes on in a woman's brain when she has an orgasm 【原文】 What women think during an orgasm Sneak-a-peek inside a woman's brain while she is having orgasm would now be possible, thanks to a scan developed by American scientists. Rutgers University researchers have discovered that sexual arousal numbs the female nervous system to such an extent that she doesn't feel as much pain-only pleasure. Orgasm affects up to 30 different parts of the brain including those responsible for emotion, touch, joy, satisfaction and memory, found researchers. The researchers asked eight women to stimulate themselves while lying under a blanket inside a Magnetic Resonance Imaging (MRI) scanner, a tunnel-like machine often used to detect brain tumours. Most women took less than five minutes to reach an orgasm although some took as long as 20. During that time, the MRI scanner took images of their brain every two seconds to show which parts became active during the orgasm. The scientists found that two minutes before the orgasm, the brain's reward centres become active, the areas usually activated when eating food and drink. Immediately before they reached the peak, other areas of the brain became affected such as the sensory cortex, which receives ''touch'' messages from parts of the body and the thalamus, which relays signals to other parts of the body. Once the orgasm has started other parts of the brain are activated such as those responsible for emotion. The final part of the brain to be activated is the hypothalamus, the ''control'' part of the brain, which regulates temperature, hunger, thirst and tiredness. At the same time another area responsible for pleasure is activated - the nucleus accumbens - as well as the caudate nucleus, which is responsible for memory. In women, orgasm produces a very extensive response across the brain and body, the Daily Mail quoted Barry Komisaruk of Rutgers University as saying. Some women raised their hands several times each session, often just a few seconds apart. So the evidence is that women tend to have longer orgasms and can experience several in rapid succession, said Komisaruk. A woman's orgasm last an average of 10-15 seconds, whilst a man's is thought to last for just six seconds.