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Self-Organized Near-Zero-Lag Synchronization Induced by Spike-Timing Dependent Plasticity in Cortical Populations.

Matias FS, Carelli PV, Mirasso CR, Copelli M - PLoS ONE (2015)

Bottom Line: We show that STDP can promote auto-organized zero-lag synchronization in unidirectionally coupled neuronal populations.We also find synchronization regimes with negative phase difference (AS) that are stable against plasticity.Finally, we show that the interplay between negative phase difference and STDP provides limited synaptic weight distribution without the need of imposing artificial boundaries.

View Article: PubMed Central - PubMed

Affiliation: Instituto de Física, Universidade Federal de Alagoas, Maceió AL 57072-970, Brazil.

ABSTRACT
Several cognitive tasks related to learning and memory exhibit synchronization of macroscopic cortical areas together with synaptic plasticity at neuronal level. Therefore, there is a growing effort among computational neuroscientists to understand the underlying mechanisms relating synchrony and plasticity in the brain. Here we numerically study the interplay between spike-timing dependent plasticity (STDP) and anticipated synchronization (AS). AS emerges when a dominant flux of information from one area to another is accompanied by a negative time lag (or phase). This means that the receiver region pulses before the sender does. In this paper we study the interplay between different synchronization regimes and STDP at the level of three-neuron microcircuits as well as cortical populations. We show that STDP can promote auto-organized zero-lag synchronization in unidirectionally coupled neuronal populations. We also find synchronization regimes with negative phase difference (AS) that are stable against plasticity. Finally, we show that the interplay between negative phase difference and STDP provides limited synaptic weight distribution without the need of imposing artificial boundaries.

No MeSH data available.


The interplay between phase difference and STDP in neuronal populations.(a) Master and Slave-Interneuron cortical-like populations. Each synaptic weight gMS (from Master to the Slave) is subject to STDP rules. (b)-(c) Membrane potentials of M (black) and S (red) populations in the AS regime (b) and in the DS regime (c) in the presence of plasticity. (d)-(e) The time delay in each cycle τi. The mean time delay τ (flat line) is negative in the AS regime (d) and positive in the DS regime (e). The AS and DS regimes are obtained modifying only one parameter in the model. The inhibitory conductances in the Slave-Interneuron population is set to gIS = 4 nS in the AS regime (b) and (d), whereas gIS = 16 nS in the DS regime (c) and (e).
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pone.0140504.g002: The interplay between phase difference and STDP in neuronal populations.(a) Master and Slave-Interneuron cortical-like populations. Each synaptic weight gMS (from Master to the Slave) is subject to STDP rules. (b)-(c) Membrane potentials of M (black) and S (red) populations in the AS regime (b) and in the DS regime (c) in the presence of plasticity. (d)-(e) The time delay in each cycle τi. The mean time delay τ (flat line) is negative in the AS regime (d) and positive in the DS regime (e). The AS and DS regimes are obtained modifying only one parameter in the model. The inhibitory conductances in the Slave-Interneuron population is set to gIS = 4 nS in the AS regime (b) and (d), whereas gIS = 16 nS in the DS regime (c) and (e).

Mentions: In order to extend our results to a cortical-like region, we investigate the effects of STDP in a population model which can exhibit AS [8]. We numerically studied the synchronization properties of two populations composed of hundred of neurons, described by the Izhikevich model, unidirectionally coupled in a master-slave configuration (see Fig 2(a) and Methods for more details). Neurons from the Master (M) population project excitatory synapses (each one with synaptic weight gMS) to excitatory neurons from Slave-Interneuron (SI) population. The inhibitory loop that is mediated by the interneuron in the 3-neuron motif, is mediated by the inhibitory neurons inside the SI population. Thus, we assume that the slave population is composed by two subgroups: the excitatory neurons, called the Slave (S) sub-population, and the inhibitory neurons, called the Interneuron (I) sub-population. Each inhibitory synapse from I to S has synaptic weight gIS. Without plasticity rules, the populations can oscillate with a well defined mean period [8]. Moreover, their activity can synchronize and the mean time delay τ between the M and S populations can be positive (DS) or negative (AS, see Methods). Similarly to the 3-neuron motif, τ is a continuous and smooth function of the synaptic weights gMS and gIS.


Self-Organized Near-Zero-Lag Synchronization Induced by Spike-Timing Dependent Plasticity in Cortical Populations.

Matias FS, Carelli PV, Mirasso CR, Copelli M - PLoS ONE (2015)

The interplay between phase difference and STDP in neuronal populations.(a) Master and Slave-Interneuron cortical-like populations. Each synaptic weight gMS (from Master to the Slave) is subject to STDP rules. (b)-(c) Membrane potentials of M (black) and S (red) populations in the AS regime (b) and in the DS regime (c) in the presence of plasticity. (d)-(e) The time delay in each cycle τi. The mean time delay τ (flat line) is negative in the AS regime (d) and positive in the DS regime (e). The AS and DS regimes are obtained modifying only one parameter in the model. The inhibitory conductances in the Slave-Interneuron population is set to gIS = 4 nS in the AS regime (b) and (d), whereas gIS = 16 nS in the DS regime (c) and (e).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4608682&req=5

pone.0140504.g002: The interplay between phase difference and STDP in neuronal populations.(a) Master and Slave-Interneuron cortical-like populations. Each synaptic weight gMS (from Master to the Slave) is subject to STDP rules. (b)-(c) Membrane potentials of M (black) and S (red) populations in the AS regime (b) and in the DS regime (c) in the presence of plasticity. (d)-(e) The time delay in each cycle τi. The mean time delay τ (flat line) is negative in the AS regime (d) and positive in the DS regime (e). The AS and DS regimes are obtained modifying only one parameter in the model. The inhibitory conductances in the Slave-Interneuron population is set to gIS = 4 nS in the AS regime (b) and (d), whereas gIS = 16 nS in the DS regime (c) and (e).
Mentions: In order to extend our results to a cortical-like region, we investigate the effects of STDP in a population model which can exhibit AS [8]. We numerically studied the synchronization properties of two populations composed of hundred of neurons, described by the Izhikevich model, unidirectionally coupled in a master-slave configuration (see Fig 2(a) and Methods for more details). Neurons from the Master (M) population project excitatory synapses (each one with synaptic weight gMS) to excitatory neurons from Slave-Interneuron (SI) population. The inhibitory loop that is mediated by the interneuron in the 3-neuron motif, is mediated by the inhibitory neurons inside the SI population. Thus, we assume that the slave population is composed by two subgroups: the excitatory neurons, called the Slave (S) sub-population, and the inhibitory neurons, called the Interneuron (I) sub-population. Each inhibitory synapse from I to S has synaptic weight gIS. Without plasticity rules, the populations can oscillate with a well defined mean period [8]. Moreover, their activity can synchronize and the mean time delay τ between the M and S populations can be positive (DS) or negative (AS, see Methods). Similarly to the 3-neuron motif, τ is a continuous and smooth function of the synaptic weights gMS and gIS.

Bottom Line: We show that STDP can promote auto-organized zero-lag synchronization in unidirectionally coupled neuronal populations.We also find synchronization regimes with negative phase difference (AS) that are stable against plasticity.Finally, we show that the interplay between negative phase difference and STDP provides limited synaptic weight distribution without the need of imposing artificial boundaries.

View Article: PubMed Central - PubMed

Affiliation: Instituto de Física, Universidade Federal de Alagoas, Maceió AL 57072-970, Brazil.

ABSTRACT
Several cognitive tasks related to learning and memory exhibit synchronization of macroscopic cortical areas together with synaptic plasticity at neuronal level. Therefore, there is a growing effort among computational neuroscientists to understand the underlying mechanisms relating synchrony and plasticity in the brain. Here we numerically study the interplay between spike-timing dependent plasticity (STDP) and anticipated synchronization (AS). AS emerges when a dominant flux of information from one area to another is accompanied by a negative time lag (or phase). This means that the receiver region pulses before the sender does. In this paper we study the interplay between different synchronization regimes and STDP at the level of three-neuron microcircuits as well as cortical populations. We show that STDP can promote auto-organized zero-lag synchronization in unidirectionally coupled neuronal populations. We also find synchronization regimes with negative phase difference (AS) that are stable against plasticity. Finally, we show that the interplay between negative phase difference and STDP provides limited synaptic weight distribution without the need of imposing artificial boundaries.

No MeSH data available.