Skip to main content
Log in

Multiplying with neurons: Compensation for irregular input spike trains by using time-dependent synaptic efficiencies

  • Published:
Biological Cybernetics Aims and scope Submit manuscript

Abstract

A leaky integrate-and-fire (LIF) neurons can act as multipliers by detecting coincidences of input spikes. However, in case of input spike trains with irregular interspike delays, false coincidences are also detected and the operation as a multiplier is degraded. This problem can be solved by using time dependent synaptic weights which are set to zero after each input spike and recover with the same time constant as the decay time of the corresponding excitatory postsynaptic potentials (EPSP). Such a mechanism results in EPSP's with amplitudes independent on the input interspike delays. Neuronal computation is then performed without frequency decoding.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

Abbreviations

C :

Capacitance of the cellular membrane (F)

Ds :

Duration of the spikes and inward current pulse. (s)

ΔV :

Contribution to the capacitor (membrane) potential reached at the end of an input spike at synapse j (V)

V + :

Membrane potential increase due to one input spike at synapse j (V)

f in :

Maximum input frequency (Hz)

f n :

Output frequency of a LIF neuron when n connected inputs fire at their maximum frequency f in . (Hz)

n :

Number of inputs connected to a neuron.

R :

Leak resistance of the membrane (Ohm)

RC :

Discharge time constant of the membrane (= R · C) (s)

RSD:

Relative standard deviation of the interspike intervals (=σ Ti / Ti)

σ Ti :

Standard deviation of the interspike intervals (s)

S :

Selectivity of the LIF neuron as a multiplier.

τ :

Time window for input spikes (s)

T i :

Average interspike interval of the spikes produced by neuron i (s).

T :

Delay between the preceding spike and the spike under consideration (s).

T in :

Average interspike interval corresponding to the maximum input frequency f in (s)

T r :

Duration of the refractory time (starting at same time as an output spike) (s)

V :

Potential of the cellular membrane or the capacitor (V)

V 0 :

Potential remaining from preceding spikes on synapse j (V)

V th :

Threshold potential for spike initiation (V)

W ij :

Time dependent synaptic weight for inputs from neuron j to neuron i. In this model, the synaptic weight is the amplitude of the input current pulse induced by the spike (A).

W ijo :

Time independent synaptic weight according to the theory of the multiplication mode for regular input spike trains with interspike delays Tin (Bugmann 1991c) (A)

References

  • Bialek W, Rieke F, De RuytervanSteveninck R, Warland D (1991) Reading a neural code. Science 252:1854–1857

    Google Scholar 

  • Buchanan JT, Moore LE, Hill R, Wallen P, Grillner S (1992) Synaptic potentials and transfer functions of lamprey spinal neurons. Biol Cybern 67:123–131

    Google Scholar 

  • Bugmann G (1991a) Neural Information carried by one spike. Proceedings of the 2nd Australian Conference on Neural Networks (ACNN' 91), Sydney, pp 235–238

  • Bugmann G (1991b) Can neurons realize multiple AND-functions? Proceedings of the 4th International Conference on Neural Networks and their Applications (Neuronimes' 91), Nimes, France, pp 757–760

  • Bugmann G (1991c) Summation and multiplication: two distinct operation domains of leaky integrate-and-fire neurons. Network 2:489–509

    Google Scholar 

  • Ferster D, Jagadeesh B (1992) EPSP-IPSP Interactions in cat visual cortex studied in vivo whole-cell patch recording. J. Neurosci 12:1262–1274

    Google Scholar 

  • Hodgkin AL, Huxley AF (1952) A quantitative description of membrane current and its application to conduction and excitation in nerve. J Physiol (London) 117:500–544

    Google Scholar 

  • Koch C, Poggio T (1992) Multiplying with synapses and neurons. In: Zornetzer S, Davis J, McKenna Th (eds) Single neuron computation. Chap. 12, pp 315–345

  • Küpfmüller K, Jenik F (1961) Über die Nachrichten Verarbeitung in der Nervenzelle. Kybernetik 1:1–6

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Bugmann, G. Multiplying with neurons: Compensation for irregular input spike trains by using time-dependent synaptic efficiencies. Biol. Cybern. 68, 87–92 (1992). https://doi.org/10.1007/BF00203140

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00203140

Keywords

Navigation