Bird Alex D, Cuntz Hermann
Warwick Systems Biology Centre, University of Warwick, Coventry, United Kingdom.
Warwick Systems Biology Doctoral Training Centre, University of Warwick, Coventry, United Kingdom.
PLoS Comput Biol. 2016 May 4;12(5):e1004897. doi: 10.1371/journal.pcbi.1004897. eCollection 2016 May.
Integration of synaptic currents across an extensive dendritic tree is a prerequisite for computation in the brain. Dendritic tapering away from the soma has been suggested to both equalise contributions from synapses at different locations and maximise the current transfer to the soma. To find out how this is achieved precisely, an analytical solution for the current transfer in dendrites with arbitrary taper is required. We derive here an asymptotic approximation that accurately matches results from numerical simulations. From this we then determine the diameter profile that maximises the current transfer to the soma. We find a simple quadratic form that matches diameters obtained experimentally, indicating a fundamental architectural principle of the brain that links dendritic diameters to signal transmission.
跨越广泛的树突状树突整合突触电流是大脑进行计算的前提条件。有人提出，远离胞体的树突逐渐变细既能平衡不同位置突触的贡献，又能使向胞体的电流传递最大化。为了确切了解这是如何实现的，需要一个关于具有任意锥度的树突中电流传递的解析解。我们在此推导了一个渐近近似，它与数值模拟结果精确匹配。据此，我们随后确定了使向胞体的电流传递最大化的直径分布。我们发现了一种简单的二次形式，它与实验获得的直径相匹配，这表明大脑存在一种将树突直径与信号传输联系起来的基本结构原理。
