The role of neuromodulators in cortical lasticity. A computational perspective
File(s)
Author(s)
Pedrosa, Victor
Clopath, Claudia
Type
Journal Article
Abstract
Neuromodulators play a ubiquitous role across the brain in regulating plasticity. With recent advances in experimental techniques, it is possible to study the effects of diverse neuromodulatory states in specific brain regions. Neuromodulators are thought to impact plasticity predominantly through two mechanisms: the gating of plasticity and the upregulation of neuronal activity. However, the consequences of these mechanisms are poorly understood and there is a need for both experimental and theoretical exploration. Here we illustrate how neuromodulatory state affects cortical plasticity through these two mechanisms. First, we explore the ability of neuromodulators to gate plasticity by reshaping the learning window for spike-timing-dependent plasticity. Using a simple computational model, we implement four different learning rules and demonstrate their effects on receptive field plasticity. We then compare the neuromodulatory effects of upregulating learning rate versus the effects of upregulating neuronal activity. We find that these seemingly similar mechanisms do not yield the same outcome: upregulating neuronal activity can lead to either a broadening or a sharpening of receptive field tuning, whereas upregulating learning rate only intensifies the sharpening of receptive field tuning. This simple model demonstrates the need for further exploration of the rich landscape of neuromodulator-mediated plasticity. Future experiments, coupled with biologically detailed computational models, will elucidate the diversity of mechanisms by which neuromodulatory state regulates cortical plasticity.
Date Issued
2017-01-10
Date Acceptance
2016-12-12
Citation
Frontiers in Synaptic Neuroscience, 2017, 8
ISSN
1663-3563
Publisher
Frontiers Media
Journal / Book Title
Frontiers in Synaptic Neuroscience
Volume
8
Copyright Statement
© 2017 Pedrosa and Clopath. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
Sponsor
Engineering & Physical Science Research Council (EPSRC)
The Leverhulme Trust
The Royal Society
Wellcome Trust
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/28119596
Grant Number
EP/M019780/1
RPG-2015-171
RG150722
200790/Z/16/Z
Subjects
acetylcholine
computational modeling
dopamine
neuromodulation
noradrenaline
synaptic plasticity
Publication Status
Published
Coverage Spatial
Switzerland
Article Number
ARTN 38