Fig. 4. SCN24 responses and targeting synaptic strengths after development.

Responses of a simulated immature SC neuron, at the position 24 in the modeled SC area (SCN24), after 100.000 training steps, using the same stimulus configurations as used in Fig. 2(a, b). The neuron is incapable of integrating its two cross-modal inputs and has responses equivalent to those of the stronger of the two. The SC targeting synapses from AES subregions (panels c) are still too weak in this phase, as in the neonatal phase, to elicit an activity in the neuron. In figures the x-axis represents the position of the pre-synaptic unisensory neuron, while the y-axis reports the synaptic strength of the incoming connection. Also projections from non-AES input areas are in a neonatal fashion, diffuse but weak (figures 4.d), and the lateral synapses among SC neurons are still immature (fig. 4.e).