• Top page
  • Timetable
  • Per session
  • Per presentation
  • How to
  • Meeting Planner



Cutting edge approaches to the architectures of cortical circuits

開催日 2014/9/12
時間 15:00 - 17:00
会場 Room B(501)
Chairperson(s) 大木 研一 / Kenichi Ohki (九州大学大学院医学研究院 / Department of Molecular Physiology, Graduate School of Medical Sciences, Kyushu University, Japan)
細谷 俊彦 / Toshihiko Hosoya (理化学研究所 脳科学総合研究センター / RIKEN Brain Science Institute, Japan)

Functional organization of synaptic strength in mouse visual cortex

  • S2-B-2-2
  • Thomas Mrsic-Flogel:1 Lee Cossell:1,2 Maria F Iacaruso:1,2 Dylan R Muir:1 Sonja Hofer:1,2 
  • 1:University of Basel, Switzerland 2:University College London, UK 

The strength of synaptic connections is a fundamental determinant of how neurons influence each other's firing. In the neocortex, excitatory connection amplitudes vary over two orders of magnitude, and there are only very few strong connections among many weaker ones. How connections of widely different strengths relate to neuronal response properties and how they contribute to information processing in local microcircuits remains unknown. Here we show that the connectivity between layer 2/3 pyramidal cells in mouse primary visual cortex (V1) is closely related to the similarity of their receptive field (RF) properties, by performing two-photon calcium imaging in vivo and then targeting the same neurons for multiple whole-cell recordings in vitro. Neurons with similar, feature-matched RFs connected frequently with strong and often reciprocal connections. In contrast, neurons with dissimilar RFs connected infrequently with weaker and unidirectional connections. Even though weak connections far outnumbered strong connections, most excitation in the local network arose from a small number of strong inputs from neurons with similar RFs, which disproportionately contribute to the feature selectivity of neural responses. Thus, the apparently complex organisation of excitatory connection strength in cortical microcircuits reflects how similarly neurons respond to stimulus features in the sensory environment.

Copyright © Neuroscience2014. All Right Reserved.