TY - JOUR TI - Apical length governs computational diversity of layer 5 pyramidal neurons AU - Galloni, Alessandro R AU - Laffere, Aeron AU - Rancz, Ede A2 - Bathellier, Brice A2 - Huguenard, John A2 - Bathellier, Brice VL - 9 PY - 2020 DA - 2020/05/28 SP - e55761 C1 - eLife 2020;9:e55761 DO - 10.7554/eLife.55761 UR - https://doi.org/10.7554/eLife.55761 AB - Anatomical similarity across the neocortex has led to the common assumption that the circuitry is modular and performs stereotyped computations. Layer 5 pyramidal neurons (L5PNs) in particular are thought to be central to cortical computation because of their extensive arborisation and nonlinear dendritic operations. Here, we demonstrate that computations associated with dendritic Ca2+ plateaus in mouse L5PNs vary substantially between the primary and secondary visual cortices. L5PNs in the secondary visual cortex show reduced dendritic excitability and smaller propensity for burst firing. This reduced excitability is correlated with shorter apical dendrites. Using numerical modelling, we uncover a universal principle underlying the influence of apical length on dendritic backpropagation and excitability, based on a Na+ channel-dependent broadening of backpropagating action potentials. In summary, we provide new insights into the modulation of dendritic excitability by apical dendrite length and show that the operational repertoire of L5PNs is not universal throughout the brain. KW - dendrites KW - pyramidal neuron KW - cortex KW - compartmental model KW - neuronal computation KW - visual cortex JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -