Department of Biology, University of Crete, Heraklion, Greece.
IMBB, FORTH, Heraklion, Greece.
Elife. 2023 Dec 6;12:e91627. doi: 10.7554/eLife.91627.
Pyramidal neurons, a mainstay of cortical regions, receive a plethora of inputs from various areas onto their morphologically distinct apical and basal trees. Both trees differentially contribute to the somatic response, defining distinct anatomical and possibly functional sub-units. To elucidate the contribution of each tree to the encoding of visual stimuli at the somatic level, we modeled the response pattern of a mouse L2/3 V1 pyramidal neuron to orientation tuned synaptic input. Towards this goal, we used a morphologically detailed computational model of a single cell that replicates electrophysiological and two-photon imaging data. Our simulations predict a synergistic effect of apical and basal trees on somatic action potential generation: basal tree activity, in the form of either depolarization or dendritic spiking, is necessary for producing somatic activity, despite the fact that most somatic spikes are heavily driven by apical dendritic spikes. This model provides evidence for synergistic computations taking place in the basal and apical trees of the L2/3 V1 neuron along with mechanistic explanations for tree-specific contributions and emphasizes the potential role of predictive and attentional feedback input in these cells.
锥体神经元是皮质区域的主要组成部分，其树突的形态明显不同，接收来自不同区域的大量输入。这两棵树对躯体反应有不同的贡献，定义了不同的解剖学和可能的功能子单元。为了阐明每棵树在躯体水平上对视觉刺激的编码的贡献，我们对一个小鼠 L2/3 V1 锥体神经元对调谐突触输入的反应模式进行了建模。为此，我们使用了一个单细胞的形态详细的计算模型，该模型复制了电生理和双光子成像数据。我们的模拟预测了树突顶和基底树突对躯体动作电位产生的协同效应：尽管大多数躯体峰主要由树突棘峰驱动，但基底树突的活动，无论是去极化还是树突棘发放，对于产生躯体活动都是必要的。该模型为 L2/3 V1 神经元的基底和树突顶树突中发生的协同计算提供了证据，并对树突特异性贡献的机制解释以及预测和注意反馈输入在这些细胞中的潜在作用进行了强调。
