Activity-dependent competition regulated by nonlinear interspike interaction in STDP: a model for visual cortical plasticity

Abstract

The development of visual cortical circuits is strongly influenced by the sensory experience during a restricted critical period, as demonstrated by the loss of neural responses to the eye that has been briefly deprived of vision. It has been suggested that, to reflect the sensory experience into the synaptic pattern, the competition between different groups of correlated inputs to a postsynaptic cell is essential and that spike-timing-dependent plasticity (STDP) may provide the basis of this type of activity-dependent competition. To predict the consequences of competition by STDP in natural physiological conditions, I here investigate the effects of nonlinear interspike interactions in STDP which are experimentally observed in the visual cortical cells. The simulations using a biophysical STDP model show that the interspike interaction can prevent the induction of competition and counteract the effect of activity-dependent feedback (ADFB) modulation of STDP that facilitates competition. However, once the competition occurs, the level of competition is not affected by the interspike interaction. These results may suggest that the interspike interaction in STDP leads to a delay in the induction of experience-dependent plasticity through suppressing synaptic competition, thereby causing a delay in the onset of critical period in the visual cortex.