Attentional Modulation of Lexical Effects on Speech Perception: Computational and Behavioral Experiments

A number of studies suggest that attention can modulate the extent to which lexical processing influences phonological processing. We propose dampening of activation as a neurophysiologically-plausible computational mechanism that can account for this type of modulation in the context of an interactive model of speech perception. Simulation results from two concrete implementations of this mechanism indicate that each of the implementations can account for attentional modulation of lexical feedback effects but that they have different consequences on the dynamics of lexical activation. We also present a behavioral test of attentional modulation of lexical effects that is not contaminated by task or stimulus effects.