Fig. 7. Maturation of SCN45 at different training steps.

The upper panels show the effect of two cross-modal and within-modal stimuli, at different spatial positions, on the neuron response. In all simulations, an auditory stimulus has been given at the center of the RF, and a second stimulus (either cross-modal or within modal) has been placed at different distances. The x-axis in the upper panels shows the distance between the two stimuli, while the y-axis is the activity of the neuron. Baseline refers to the neuron response to the central auditory stimulus given alone.

The bottom panels show the sum of all trained synapses entering the neuron (excitatory descending, excitatory ascending, lateral, inhibitory descending) at different training steps. It is worth noting that descending synapses start to increase abruptly after reaching a given threshold (approximately at step 52000), than rapidly assess at a saturation level. Ascending synapses decrease with training, while lateral synapses become negative, reflecting the predominance of inhibition. These synapses also exhibit the slower dynamics.