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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.


STDP changes the relation between the time delay τ and the synaptic weights.STDP promotes zero-lag synchronization (τ ≈ 0): (a)-(c) τ as a function of the initial excitatory weights  with and without STDP (represented by circles and squares, respectively). (d)-(f) τ as a function of the inhibitory weights gIS with and without STDP. (g)-(h) τ (color coded) in the (gIS, ) parameter space without plasticity (g) and with STDP (h). The near-zero-lag regime is represented by the grey regions, AS (τ < 0) by the red regions and DS (τ > 0) by the blue ones. In the presence of STDP, τ is determined by the local amount of inhibition gIS.
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pone.0140504.g004: STDP changes the relation between the time delay τ and the synaptic weights.STDP promotes zero-lag synchronization (τ ≈ 0): (a)-(c) τ as a function of the initial excitatory weights with and without STDP (represented by circles and squares, respectively). (d)-(f) τ as a function of the inhibitory weights gIS with and without STDP. (g)-(h) τ (color coded) in the (gIS, ) parameter space without plasticity (g) and with STDP (h). The near-zero-lag regime is represented by the grey regions, AS (τ < 0) by the red regions and DS (τ > 0) by the blue ones. In the presence of STDP, τ is determined by the local amount of inhibition gIS.

Mentions: The presence of plasticity and the inhibitory dynamical loop can lead unidirectionally coupled neuronal populations to self-organize into near-zero-lag oscillations. The continuous transition from DS to AS, mediated by the excitatory synaptic weights gMS in the absence of STDP, collapses into a flat line in the presence of STDP (see Fig 4(a)–4(c)). For 7 nS < gIS < 12 nS the system exhibits time delay τ ≃ 0 (see Fig 4(h)). This means that independently of the initial values of the excitatory weights, the inhibitory loop together with STDP rules are sufficient to provide a τ ≈ 0 synchronized solution.


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)

STDP changes the relation between the time delay τ and the synaptic weights.STDP promotes zero-lag synchronization (τ ≈ 0): (a)-(c) τ as a function of the initial excitatory weights  with and without STDP (represented by circles and squares, respectively). (d)-(f) τ as a function of the inhibitory weights gIS with and without STDP. (g)-(h) τ (color coded) in the (gIS, ) parameter space without plasticity (g) and with STDP (h). The near-zero-lag regime is represented by the grey regions, AS (τ < 0) by the red regions and DS (τ > 0) by the blue ones. In the presence of STDP, τ is determined by the local amount of inhibition gIS.
© Copyright Policy
Related In: Results  -  Collection

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

pone.0140504.g004: STDP changes the relation between the time delay τ and the synaptic weights.STDP promotes zero-lag synchronization (τ ≈ 0): (a)-(c) τ as a function of the initial excitatory weights with and without STDP (represented by circles and squares, respectively). (d)-(f) τ as a function of the inhibitory weights gIS with and without STDP. (g)-(h) τ (color coded) in the (gIS, ) parameter space without plasticity (g) and with STDP (h). The near-zero-lag regime is represented by the grey regions, AS (τ < 0) by the red regions and DS (τ > 0) by the blue ones. In the presence of STDP, τ is determined by the local amount of inhibition gIS.
Mentions: The presence of plasticity and the inhibitory dynamical loop can lead unidirectionally coupled neuronal populations to self-organize into near-zero-lag oscillations. The continuous transition from DS to AS, mediated by the excitatory synaptic weights gMS in the absence of STDP, collapses into a flat line in the presence of STDP (see Fig 4(a)–4(c)). For 7 nS < gIS < 12 nS the system exhibits time delay τ ≃ 0 (see Fig 4(h)). This means that independently of the initial values of the excitatory weights, the inhibitory loop together with STDP rules are sufficient to provide a τ ≈ 0 synchronized solution.

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.