Format

Send to

Choose Destination
PLoS One. 2008;3(12):e3947. doi: 10.1371/journal.pone.0003947. Epub 2008 Dec 16.

Cholinergic neuromodulation changes phase response curve shape and type in cortical pyramidal neurons.

Author information

1
Howard Hughes Medical Institute, The Salk Institute for Biological Studies, La Jolla, California, United States of America.

Abstract

Spike generation in cortical neurons depends on the interplay between diverse intrinsic conductances. The phase response curve (PRC) is a measure of the spike time shift caused by perturbations of the membrane potential as a function of the phase of the spike cycle of a neuron. Near the rheobase, purely positive (type I) phase-response curves are associated with an onset of repetitive firing through a saddle-node bifurcation, whereas biphasic (type II) phase-response curves point towards a transition based on a Hopf-Andronov bifurcation. In recordings from layer 2/3 pyramidal neurons in cortical slices, cholinergic action, consistent with down-regulation of slow voltage-dependent potassium currents such as the M-current, switched the PRC from type II to type I. This is the first report showing that cholinergic neuromodulation may cause a qualitative switch in the PRCs type implying a change in the fundamental dynamical mechanism of spike generation.

PMID:
19079601
PMCID:
PMC2596483
DOI:
10.1371/journal.pone.0003947
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Public Library of Science Icon for PubMed Central
Loading ...
Support Center