Learning mechanisms to account for the speed, selectivity and invariance of responses in the visual cortex

In this thesis I propose various activity-driven synaptic plasticity mechanisms that could account for the speed, selectivity and invariance of the neuronal responses in the visual cortex. Their biological plausibility is discussed. I also present the results of a relevant psychophysical experiment demonstrating that familiarity can accelerate visual processing. Beyond these results on the visual system, the studies presented here also credit the hypothesis that the brain uses the spike times to encode, decode, and process information – a theory referred to as ‘temporal coding'. In such a framework the Spike Timing Dependent Plasticity may play a key role, by detecting repeating spike patterns and by generating faster and faster responses to those patterns.