Neuron:华人学者新发现:为啥有些声音让人害怕?

2017-06-27 佚名 学术经纬

很多人在听到警报声,或者恐怖电影中的音乐时会自动产生害怕或恐惧的感觉,那么你有没有想过这种联系是怎么建立起来的呢?这其实是神经科学家们一直以来在探索的一个问题。直到最近,一项来自美国埃默里大学(Emory University)的研究开始揭开了这个问题的答案。科学家们发现,位于神经细胞外的一种称之为“神经周围网格(Perineuronal Net)”的结构中的变化,对于建立声音和恐惧感之间的联系,

很多人在听到警报声,或者恐怖电影中的音乐时会自动产生害怕或恐惧的感觉,那么你有没有想过这种联系是怎么建立起来的呢?这其实是神经科学家们一直以来在探索的一个问题。直到最近,一项来自美国埃默里大学(Emory University)的研究开始揭开了这个问题的答案。科学家们发现,位于神经细胞外的一种称之为“神经周围网格(Perineuronal Net)”的结构中的变化,对于建立声音和恐惧感之间的联系,以及将其储存在记忆中,发挥着至关重要的作用。这项研究发表了在最近的神经科学权威学术期刊《Neuron》杂志上。


▲Rober Liu教授是本项研究的主要负责人之一(图片来源:埃默里大学)

声音条件恐惧反射是条件反射的一种,当听到某种特定的声音时便会产生恐惧感,对于许多人来说这都是正常的生理现象。而这种反射的失调也会导致精神疾病,最典型的例子是创伤后应激综合征(PTSD),该病患者对于特定的声音刺激会产生过度的反应,并出现回避、暴力、思维混乱等症状。因此,找到声音条件恐惧反射产生的机制,就有可能会这些患者带来新的治疗方法。

经典的神经生物学研究认为,大脑中的杏仁核是产生恐惧的主要部位。不过,最近越来越多的研究发现,声音条件恐惧反射的产生以及相应记忆的形成,与听觉皮层有密不可分的关系。听觉皮层被发现能够长期储存引起恐惧反应的声音信号,在重新受到该声音刺激时,便向杏仁核发出信号,产生恐惧感。但是,大脑皮层如何储存这些相关的声音信号记忆并不为人所知。


▲我们知道杏核仁能产生恐惧感,但听觉皮层如何储存“恐惧声音”的记忆,依然不为人知(图片来源:Huffington Post)

为了研究声音条件恐惧反射产生的机制,来自埃默里大学的科研人员使用了一种小鼠的恐惧反射模型。为了在小鼠中建立这种反射,他们先给小鼠听一个特定的声音,随后对小鼠进行电击以产生痛感。如此反复10次以后,小鼠就能建立起该声音和电击之间的联系,并形成记忆。当再次给小鼠播放该声音时,小鼠因为害怕遭到电击而一动不动,进入冻结的状态,不管它是否会真的遭到电击。而这种记忆能够在小鼠内存在数天之久。


▲参加该实验的小鼠,心情大概是崩溃的……(图片来源:ExpertBeacon)

科研人员首先检测了小鼠听觉皮层内在初次建立恐惧反射后4个小时之内的基因表达变化状况,这4个小时是声音条件恐惧反射记忆形成最关键的时期。出乎意料的是,他们发现表达量变化最大的基因中包括了蛋白聚糖家族的多个基因,在这段时间中,蛋白聚糖的表达量明显上升。蛋白聚糖是细胞外基质的主要的组成部分,它们能够形成类似于软骨一样的称之为神经周边网格的网格状结构。通常神经周边网格被认为对神经系统的发育和神经突触的形成及成熟起结构上的支持作用,在成年动物中它们的结构较为稳定,并不发生很大的变化。而在这项研究中,小鼠听觉皮层的神经周边网格在恐惧反射的形成中相当活跃,其组成部分蛋白聚糖的表达量在反射建立后的4个小时达到最大,并在24小时后恢复到原水平。

▲小鼠神经周边网格在恐惧反射建立的4个小时后,表现得非常活跃(图片来源:《细胞》)

然后,科研人员使用了软骨素酶破坏了神经周边网格的结构,来研究它对于声音条件恐惧反射形成的作用。他们发现,没有了神经周边网格的小鼠,在恐惧反射形成后30分钟再听到声音刺激时,表现出了与预期一致的冻结行为。但是,当24小时之后再进行同样的测试时,这种冻结行为消失了。也就是说,这些小鼠能够形成正常的声音条件恐惧反射,但是,它们不能形成对于这种反射的记忆。

科研人员就此得出的结论是,听觉皮层的神经周边网格对于恐惧反射的形成没有作用,但是对于将该反射进行记忆储存有不可或缺的作用。这一结果再次出乎了科学家们的预料,因为传统观点认为,失去了神经周边网格之后,神经细胞变得更为自由,因此更易于形成新的突触,从而增强记忆形成。这项研究的结果显示,神经周边网格与突触之间的联系并没有那么简单。神经周边网格至少对于恐惧反射的记忆形成起着关键的作用。


▲这项研究有望改变PTSD的治疗(图片来源:YouthVoices.net)

这项研究结果增加了我们对于大脑记忆形成过程的认识,发现了在收集新信息和转化为记忆的过程中的关键时间段的机制。此外,这项研究对于治疗像创伤后应激综合征这样的疾病也有重要的意义。研究的共同通讯作者之一、埃默里大学生物系副教授Robert  Liu博士表示:“这意味着在人经历创伤后可能会有一个时间窗口,在这段时间内你可以给他们一种药物,减少大脑特定区域的活动,这有可能阻止特定创伤记忆的形成。”

原始出处:
Sunayana B. Banerjee, Vanessa A. Gutzeit et al.Perineuronal Nets in the Adult Sensory Cortex Are Necessary for Fear Learning.Neuron

版权声明:
本网站所有内容来源注明为“梅斯医学”或“MedSci原创”的文字、图片和音视频资料,版权均属于梅斯医学所有。非经授权,任何媒体、网站或个人不得转载,授权转载时须注明来源为“梅斯医学”。其它来源的文章系转载文章,或“梅斯号”自媒体发布的文章,仅系出于传递更多信息之目的,本站仅负责审核内容合规,其内容不代表本站立场,本站不负责内容的准确性和版权。如果存在侵权、或不希望被转载的媒体或个人可与我们联系,我们将立即进行删除处理。
在此留言
评论区 (5)
#插入话题
  1. [GetPortalCommentsPageByObjectIdResponse(id=1921179, encodeId=59a619211e9d1, content=<a href='/topic/show?id=6bfa58133ef' target=_blank style='color:#2F92EE;'>#新发现#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=25, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=58133, encryptionId=6bfa58133ef, topicName=新发现)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=644e456, createdName=vera_1203, createdTime=Sat Apr 14 20:01:00 CST 2018, time=2018-04-14, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1751839, encodeId=dace1e5183902, content=<a href='/topic/show?id=9b6a12e0155' target=_blank style='color:#2F92EE;'>#Neuron#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=31, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=12701, encryptionId=9b6a12e0155, topicName=Neuron)], attachment=null, authenticateStatus=null, createdAvatar=null, createdBy=c9c736410065, createdName=by2021, createdTime=Thu Oct 26 19:01:00 CST 2017, time=2017-10-26, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1581958, encodeId=78221581958fa, content=<a href='/topic/show?id=830c35868ec' target=_blank style='color:#2F92EE;'>#华人#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=29, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=35868, encryptionId=830c35868ec, topicName=华人)], attachment=null, authenticateStatus=null, createdAvatar=null, createdBy=3f7716881423, createdName=ms4468361851264128, createdTime=Thu Jun 29 05:01:00 CST 2017, time=2017-06-29, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1622996, encodeId=536f1622996c1, content=<a href='/topic/show?id=54a7358e4cb' target=_blank style='color:#2F92EE;'>#华人学者#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=38, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=35874, encryptionId=54a7358e4cb, topicName=华人学者)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=395f25, createdName=爆笑小医, createdTime=Thu Jun 29 05:01:00 CST 2017, time=2017-06-29, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=216008, encodeId=79ac21600839, content=看看了解一下了, beContent=null, objectType=article, channel=null, level=null, likeNumber=59, replyNumber=0, topicName=null, topicId=null, topicList=[], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=90f31612316, createdName=xiaotaiyang1, createdTime=Tue Jun 27 14:55:20 CST 2017, time=2017-06-27, status=1, ipAttribution=)]
  2. [GetPortalCommentsPageByObjectIdResponse(id=1921179, encodeId=59a619211e9d1, content=<a href='/topic/show?id=6bfa58133ef' target=_blank style='color:#2F92EE;'>#新发现#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=25, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=58133, encryptionId=6bfa58133ef, topicName=新发现)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=644e456, createdName=vera_1203, createdTime=Sat Apr 14 20:01:00 CST 2018, time=2018-04-14, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1751839, encodeId=dace1e5183902, content=<a href='/topic/show?id=9b6a12e0155' target=_blank style='color:#2F92EE;'>#Neuron#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=31, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=12701, encryptionId=9b6a12e0155, topicName=Neuron)], attachment=null, authenticateStatus=null, createdAvatar=null, createdBy=c9c736410065, createdName=by2021, createdTime=Thu Oct 26 19:01:00 CST 2017, time=2017-10-26, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1581958, encodeId=78221581958fa, content=<a href='/topic/show?id=830c35868ec' target=_blank style='color:#2F92EE;'>#华人#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=29, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=35868, encryptionId=830c35868ec, topicName=华人)], attachment=null, authenticateStatus=null, createdAvatar=null, createdBy=3f7716881423, createdName=ms4468361851264128, createdTime=Thu Jun 29 05:01:00 CST 2017, time=2017-06-29, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1622996, encodeId=536f1622996c1, content=<a href='/topic/show?id=54a7358e4cb' target=_blank style='color:#2F92EE;'>#华人学者#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=38, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=35874, encryptionId=54a7358e4cb, topicName=华人学者)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=395f25, createdName=爆笑小医, createdTime=Thu Jun 29 05:01:00 CST 2017, time=2017-06-29, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=216008, encodeId=79ac21600839, content=看看了解一下了, beContent=null, objectType=article, channel=null, level=null, likeNumber=59, replyNumber=0, topicName=null, topicId=null, topicList=[], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=90f31612316, createdName=xiaotaiyang1, createdTime=Tue Jun 27 14:55:20 CST 2017, time=2017-06-27, status=1, ipAttribution=)]
    2017-10-26 by2021
  3. [GetPortalCommentsPageByObjectIdResponse(id=1921179, encodeId=59a619211e9d1, content=<a href='/topic/show?id=6bfa58133ef' target=_blank style='color:#2F92EE;'>#新发现#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=25, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=58133, encryptionId=6bfa58133ef, topicName=新发现)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=644e456, createdName=vera_1203, createdTime=Sat Apr 14 20:01:00 CST 2018, time=2018-04-14, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1751839, encodeId=dace1e5183902, content=<a href='/topic/show?id=9b6a12e0155' target=_blank style='color:#2F92EE;'>#Neuron#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=31, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=12701, encryptionId=9b6a12e0155, topicName=Neuron)], attachment=null, authenticateStatus=null, createdAvatar=null, createdBy=c9c736410065, createdName=by2021, createdTime=Thu Oct 26 19:01:00 CST 2017, time=2017-10-26, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1581958, encodeId=78221581958fa, content=<a href='/topic/show?id=830c35868ec' target=_blank style='color:#2F92EE;'>#华人#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=29, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=35868, encryptionId=830c35868ec, topicName=华人)], attachment=null, authenticateStatus=null, createdAvatar=null, createdBy=3f7716881423, createdName=ms4468361851264128, createdTime=Thu Jun 29 05:01:00 CST 2017, time=2017-06-29, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1622996, encodeId=536f1622996c1, content=<a href='/topic/show?id=54a7358e4cb' target=_blank style='color:#2F92EE;'>#华人学者#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=38, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=35874, encryptionId=54a7358e4cb, topicName=华人学者)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=395f25, createdName=爆笑小医, createdTime=Thu Jun 29 05:01:00 CST 2017, time=2017-06-29, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=216008, encodeId=79ac21600839, content=看看了解一下了, beContent=null, objectType=article, channel=null, level=null, likeNumber=59, replyNumber=0, topicName=null, topicId=null, topicList=[], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=90f31612316, createdName=xiaotaiyang1, createdTime=Tue Jun 27 14:55:20 CST 2017, time=2017-06-27, status=1, ipAttribution=)]
  4. [GetPortalCommentsPageByObjectIdResponse(id=1921179, encodeId=59a619211e9d1, content=<a href='/topic/show?id=6bfa58133ef' target=_blank style='color:#2F92EE;'>#新发现#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=25, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=58133, encryptionId=6bfa58133ef, topicName=新发现)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=644e456, createdName=vera_1203, createdTime=Sat Apr 14 20:01:00 CST 2018, time=2018-04-14, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1751839, encodeId=dace1e5183902, content=<a href='/topic/show?id=9b6a12e0155' target=_blank style='color:#2F92EE;'>#Neuron#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=31, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=12701, encryptionId=9b6a12e0155, topicName=Neuron)], attachment=null, authenticateStatus=null, createdAvatar=null, createdBy=c9c736410065, createdName=by2021, createdTime=Thu Oct 26 19:01:00 CST 2017, time=2017-10-26, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1581958, encodeId=78221581958fa, content=<a href='/topic/show?id=830c35868ec' target=_blank style='color:#2F92EE;'>#华人#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=29, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=35868, encryptionId=830c35868ec, topicName=华人)], attachment=null, authenticateStatus=null, createdAvatar=null, createdBy=3f7716881423, createdName=ms4468361851264128, createdTime=Thu Jun 29 05:01:00 CST 2017, time=2017-06-29, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1622996, encodeId=536f1622996c1, content=<a href='/topic/show?id=54a7358e4cb' target=_blank style='color:#2F92EE;'>#华人学者#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=38, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=35874, encryptionId=54a7358e4cb, topicName=华人学者)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=395f25, createdName=爆笑小医, createdTime=Thu Jun 29 05:01:00 CST 2017, time=2017-06-29, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=216008, encodeId=79ac21600839, content=看看了解一下了, beContent=null, objectType=article, channel=null, level=null, likeNumber=59, replyNumber=0, topicName=null, topicId=null, topicList=[], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=90f31612316, createdName=xiaotaiyang1, createdTime=Tue Jun 27 14:55:20 CST 2017, time=2017-06-27, status=1, ipAttribution=)]
  5. [GetPortalCommentsPageByObjectIdResponse(id=1921179, encodeId=59a619211e9d1, content=<a href='/topic/show?id=6bfa58133ef' target=_blank style='color:#2F92EE;'>#新发现#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=25, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=58133, encryptionId=6bfa58133ef, topicName=新发现)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=644e456, createdName=vera_1203, createdTime=Sat Apr 14 20:01:00 CST 2018, time=2018-04-14, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1751839, encodeId=dace1e5183902, content=<a href='/topic/show?id=9b6a12e0155' target=_blank style='color:#2F92EE;'>#Neuron#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=31, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=12701, encryptionId=9b6a12e0155, topicName=Neuron)], attachment=null, authenticateStatus=null, createdAvatar=null, createdBy=c9c736410065, createdName=by2021, createdTime=Thu Oct 26 19:01:00 CST 2017, time=2017-10-26, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1581958, encodeId=78221581958fa, content=<a href='/topic/show?id=830c35868ec' target=_blank style='color:#2F92EE;'>#华人#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=29, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=35868, encryptionId=830c35868ec, topicName=华人)], attachment=null, authenticateStatus=null, createdAvatar=null, createdBy=3f7716881423, createdName=ms4468361851264128, createdTime=Thu Jun 29 05:01:00 CST 2017, time=2017-06-29, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1622996, encodeId=536f1622996c1, content=<a href='/topic/show?id=54a7358e4cb' target=_blank style='color:#2F92EE;'>#华人学者#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=38, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=35874, encryptionId=54a7358e4cb, topicName=华人学者)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=395f25, createdName=爆笑小医, createdTime=Thu Jun 29 05:01:00 CST 2017, time=2017-06-29, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=216008, encodeId=79ac21600839, content=看看了解一下了, beContent=null, objectType=article, channel=null, level=null, likeNumber=59, replyNumber=0, topicName=null, topicId=null, topicList=[], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=90f31612316, createdName=xiaotaiyang1, createdTime=Tue Jun 27 14:55:20 CST 2017, time=2017-06-27, status=1, ipAttribution=)]
    2017-06-27 xiaotaiyang1

    看看了解一下了

    0

相关资讯

Nature:“麻麻素”让妈妈更称职

像许多新生的哺乳动物一样,老鼠宝宝的哭声也会引起妈妈的注意。不过妈妈们并不本能地认识到这些哭声的需求;她必须学习幼崽的哭声,就跟人一样。最近,纽约大学医学院的一个研究小组发现一种“妈妈素”能帮助妈妈们学习的一个关键存在。这个“妈妈素”其实就是催产素(oxytocin)。大脑对催产素产生反应后,雌性小鼠才会对哭泣的幼崽表现出母亲的关心和注意力。这篇研究在线发表在最新的Nature。纽约大学医学院的研

PLoS Comput Biol:听觉皮层神经也能辨别时间?

没有声音,我们的听觉系统是如何辨别时间的呢?最近,一项发表在plos computational biology的文章对大脑中感知声音的主要枢纽--听觉皮层的神经活动如何辨别时间的声学模式进行了相关研究。 来自伦敦大学的研究人员描述了一种新的模式,他们认为听觉皮层的神经元能够将兴奋性输入信号和抑制性输入信号进行混合,对时间信息进行编码。 研究人员打了一个比方,当你踩下油门,你的