感官刺激的树突编码由深层皮层内部神经元控制
Masanori Murayama1, Enrique Pérez-Garci, Thomas Nevian
1Physiologisches Institut, Universität Bern, Bühlplatz 5, CH-3012 Bern, Switzerland.
Nature
|January 20, 2009
概括
在第5层 (L5) 金字塔神经元中的活性树突导电量增强了计算能力. 抑制控制L5金字塔树突的感觉编码,使线性动态范围适应.
科学领域:
- 神经科学是一个神经科学.
- 计算神经科学是一种神经科学.
- 细胞神经科学 细胞神经科学
背景情况:
- 活跃的树突导电量显著增强神经元的计算能力和峰值活动.
- 第5层 (L5) 的金字塔神经元利用顶端树突性通道进行平原潜力,影响输入/输出增益和突发发射.
研究的目的:
- 为了研究各种输入如何影响活体树突性质 in vivo.
- 探索L5金字塔树突中感官刺激强度的编码.
- 阐明抑制神经元在调节树突活动中的作用.
主要方法:
- 利用一种新的光纤方法记录L5金字塔树突中的树突变化.
- 在清醒和麻醉的老鼠中记录了L5金字塔树突群中的活动.
- 在单一的顶端状树上进行了体外记录.
主要成果:
- 感官刺激的强度是由L5金字塔细胞的群体树突反应以分级的方式编码的.
- 一个特定的抑制神经元子集,由L5突触输入激活,控制刺激-反应函数的斜率.
- 通过内部神经元的局部抑制阻断了邻近L5金字塔神经元中的树突峰启动.
结论:
- 在清醒的动物中,皮质微电路依赖于活性L5金字塔状树的特性和对抑制的敏感性.
- 这种微电路使得角树突的本地种群能够在它们的动态范围中线性编码感官刺激.
- 抑制性控制对于皮质电路中的自适应性感官编码至关重要.
相关概念视频
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The receptor level:
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