Stochastic and deterministic dynamics of intrinsically irregular firing in cortical inhibitory interneurons

Date

Aug 30, 2016

Time

2:00 PM - 3:00 PM

Speaker

Hugh Robinson (Cambridge University

Affiliation

UK)

Language

en

Main Topic

Physik

Other Topics

Physik

Host

Advanced Study Group

Description

Most cortical neurons fire regularly when excited by a constant stimulus. In contrast, irregular-spiking (IS) interneurons are remarkable for the intrinsic variability of their spike timing, which can synchronize amongst IS cells via specific gap junctions. We have studied the biophysical mechanisms of this irregular spiking, and how IS cells fire in the context of synchronous network oscillations. Using patch-clamp recordings, artificial dynamic conductance injection, pharmacological analysis and computational modelling, we show that spike time irregularity is generated by a nonlinear dynamical interaction of voltage-dependent sodium and fast-inactivating potassium channels just below spike threshold, amplifying channel noise. This active irregularity may help IS cells synchronize with each other at gamma range frequencies, while resisting synchronization to lower input frequencies.

Last modified: Aug 30, 2016, 9:36:36 AM