ePoster

Network integration of neurons with different (somatic vs. dendritic) axon origin: A computational modelling approach

Livia Klostermann, Andreas Draguhn, Martin Both
FENS Forum 2024(2024)
Messe Wien Exhibition & Congress Center, Vienna, Austria

Conference

FENS Forum 2024

Messe Wien Exhibition & Congress Center, Vienna, Austria

Resources

Authors & Affiliations

Livia Klostermann, Andreas Draguhn, Martin Both

Abstract

Cortical principal neurons receive multiple synaptic inputs via their dendrites, integrate them in their soma and once a threshold is reached, generate action potentials. Dendritic branches express multiple mechanisms for modulation and integration of signals, depending on the spatiotemporal pattern of arriving inputs. Recently, we have reported a new structural feature of pyramidal neurons affecting neuronal signal processing: axon localization. In about 50% of CA1 hippocampal pyramidal cells, the axon emerges from a basal dendrite instead of the soma. Input to the axon-carrying dendrite (AcD) is privileged to trigger action potentials, especially during strong perisomatic inhibition particularly pronounced during network oscillations. Therefore, we hypothesized that ‘AcD cells’ play a specific role in network oscillations and their synchronization. To analyze this, we implemented a multi-compartment model of pyramidal cells using the NEURON simulation environment in Python. We then constructed networks of either AcD or non-AcD cells and added inhibitory cells to simulate perisomatic inhibition. In particular, the network contained excitatory (E) and inhibitory (I) neurons in a 10:1 ratio with 50% I->E, 25% E->I, and 3% E->E connectivity. We simulated two different scenarios: 1) One network constructed as described above, 2) two independently initialized networks sparsely connected to each other via pyramidal cells. The individual networks expressed stable gamma-oscillations (~40 Hz) upon constant random noise input in all cases. In scenario 2), neuronal activity was synchronized between connected networks after an asynchronous activation onset. Preliminary results suggest that AcD cells foster stronger synchronization within and between two connected, remotely localized networks.

Unique ID: fens-24/network-integration-neurons-with-different-bb9227aa