The response of a neuron in the visual cortex to stimuli of different
contrast placed in its receptive field is commonly characterized
using the contrast response curve. When attention is directed into
the receptive field of a V4 neuron, its contrast response curve is
shifted to lower contrast values (Reynolds et al., 2000). The neuron
will thus be able to respond to weaker stimuli than it responded
to without attention. Attention also increases the coherence between
neurons responding to the same stimulus (Fries et al., 2001). We
studied how the firing rate and synchrony of a densely interconnected
cortical network varied with contrast and how they were modulated
by attention. The changes in contrast and attention were modeled
as changes in driving current to the network neurons. We found that
an increased driving current to the excitatory neurons increased
the overall firing rate of the network, whereas variation of the
driving current to inhibitory neurons modulated the synchrony of
the network. We explain the synchrony modulation in terms of a locking
phenomenon during which the ratio of excitatory to inhibitory firing
rates is approximately constant for a range of driving current values.
We explored the hypothesis that contrast is represented primarily
as a drive to the excitatory neurons, whereas attention corresponds
to a reduction in driving current to the inhibitory neurons. Using
this hypothesis, the model reproduces the following experimental
observations: (1) the firing rate of the excitatory neurons increases
with contrast; (2) for high contrast stimuli, the firing rate saturates
and the network synchronizes; (3) attention shifts the contrast response
curve to lower contrast values; (4) attention leads to stronger synchronization
that starts at a lower value of the contrast compared with the attend-away
condition. In addition, it predicts that attention increases the
delay between the inhibitory and excitatory synchronous volleys produced
by the network, allowing the stimulus to recruit more downstream
neurons.
2006\Attentional modulation of firing rate and synchrony in a model cortical network.pdf
file
Attentional modulation of firing rate and synchrony in a model cortical network.pdf:2006\\Attentional modulation of firing rate and synchrony in a model cortical network.pdf:PDF
%0 Journal Article
%1 C2006
%A C, Buia
%A P., Tiesinga
%D 2006
%J J Comput Neurosci
%K , Attention Delay Synchronization Synchrony modulation
%P 247-264
%T Attentional modulation of firing rate and synchrony in a model cortical
network
%V 20
%X The response of a neuron in the visual cortex to stimuli of different
contrast placed in its receptive field is commonly characterized
using the contrast response curve. When attention is directed into
the receptive field of a V4 neuron, its contrast response curve is
shifted to lower contrast values (Reynolds et al., 2000). The neuron
will thus be able to respond to weaker stimuli than it responded
to without attention. Attention also increases the coherence between
neurons responding to the same stimulus (Fries et al., 2001). We
studied how the firing rate and synchrony of a densely interconnected
cortical network varied with contrast and how they were modulated
by attention. The changes in contrast and attention were modeled
as changes in driving current to the network neurons. We found that
an increased driving current to the excitatory neurons increased
the overall firing rate of the network, whereas variation of the
driving current to inhibitory neurons modulated the synchrony of
the network. We explain the synchrony modulation in terms of a locking
phenomenon during which the ratio of excitatory to inhibitory firing
rates is approximately constant for a range of driving current values.
We explored the hypothesis that contrast is represented primarily
as a drive to the excitatory neurons, whereas attention corresponds
to a reduction in driving current to the inhibitory neurons. Using
this hypothesis, the model reproduces the following experimental
observations: (1) the firing rate of the excitatory neurons increases
with contrast; (2) for high contrast stimuli, the firing rate saturates
and the network synchronizes; (3) attention shifts the contrast response
curve to lower contrast values; (4) attention leads to stronger synchronization
that starts at a lower value of the contrast compared with the attend-away
condition. In addition, it predicts that attention increases the
delay between the inhibitory and excitatory synchronous volleys produced
by the network, allowing the stimulus to recruit more downstream
neurons.
@article{C2006,
abstract = {The response of a neuron in the visual cortex to stimuli of different
contrast placed in its receptive field is commonly characterized
using the contrast response curve. When attention is directed into
the receptive field of a V4 neuron, its contrast response curve is
shifted to lower contrast values (Reynolds et al., 2000). The neuron
will thus be able to respond to weaker stimuli than it responded
to without attention. Attention also increases the coherence between
neurons responding to the same stimulus (Fries et al., 2001). We
studied how the firing rate and synchrony of a densely interconnected
cortical network varied with contrast and how they were modulated
by attention. The changes in contrast and attention were modeled
as changes in driving current to the network neurons. We found that
an increased driving current to the excitatory neurons increased
the overall firing rate of the network, whereas variation of the
driving current to inhibitory neurons modulated the synchrony of
the network. We explain the synchrony modulation in terms of a locking
phenomenon during which the ratio of excitatory to inhibitory firing
rates is approximately constant for a range of driving current values.
We explored the hypothesis that contrast is represented primarily
as a drive to the excitatory neurons, whereas attention corresponds
to a reduction in driving current to the inhibitory neurons. Using
this hypothesis, the model reproduces the following experimental
observations: (1) the firing rate of the excitatory neurons increases
with contrast; (2) for high contrast stimuli, the firing rate saturates
and the network synchronizes; (3) attention shifts the contrast response
curve to lower contrast values; (4) attention leads to stronger synchronization
that starts at a lower value of the contrast compared with the attend-away
condition. In addition, it predicts that attention increases the
delay between the inhibitory and excitatory synchronous volleys produced
by the network, allowing the stimulus to recruit more downstream
neurons.},
added-at = {2012-01-27T14:10:42.000+0100},
author = {C, Buia and P., Tiesinga},
biburl = {https://www.bibsonomy.org/bibtex/2a63a3a422b2929d01c8031c654a15b37/muhe},
file = {Attentional modulation of firing rate and synchrony in a model cortical network.pdf:2006\\Attentional modulation of firing rate and synchrony in a model cortical network.pdf:PDF},
interhash = {eb4ee35ab75729986df31b238969dd0b},
intrahash = {a63a3a422b2929d01c8031c654a15b37},
journal = {J Comput Neurosci},
keywords = {, Attention Delay Synchronization Synchrony modulation},
owner = {Mu},
pages = {247-264},
pdf = {2006\Attentional modulation of firing rate and synchrony in a model cortical network.pdf},
timestamp = {2012-01-27T14:10:47.000+0100},
title = {Attentional modulation of firing rate and synchrony in a model cortical
network},
volume = 20,
year = 2006
}