Modeling apical and basal tree contribution to orientation selectivity in a mouse primary visual cortex layer 2/3 pyramidal cell
Abstract
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.
Data availability
The code and all data used/generated in the manuscript will be publicly available in a GitHub repository https://github.com/kepetousakis/petousakis_etal_2023.
Article and author information
Author details
Funding
ERC Starting Grant dEMORY (GA 311435)
- Panayiota Poirazi
H2020-MSCA ITN 2019, SmartNets (GA 860949)
- Panayiota Poirazi
Fondation Santé a FORTH-Synergy Grant (EVO-NMDA)
- Panayiota Poirazi
H2020-FETOPEN-2018-2019-2020-01NEUREKA (GA 863245)
- Panayiota Poirazi
NIH NEI (R01 grant EY-024019)
- Stelios Smirnakis
NINDS (R21 grant NS088457)
- Stelios Smirnakis
Hellenic Foundation for Research and Innovation (PhD Scholarship (no. 6731))
- Konstantinos-Evangelos Petousakis
FORTH-Synergy Grant (FlexBe)
- Athanasia Papoutsi
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Petousakis et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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