Figure 1. Effect of previous trial on simultaneity judgments.

Proportion of trials judged to be simultaneous as a function of Stimulus Onset Asynchrony (SOA) for two representative participants, one typical adult (a), one autistic adult (b). Negative SOAs indicate the tone preceded the luminance onset, positive that the tone followed the luminance onset. The data were divided into those where audition leads in the previous trial (blue symbols) and those where it lags (red symbols), ignoring trials preceded by simultaneous audiovisual stimuli. Colour-coded curves are best-fitting Gaussian distributions, free to vary in mean (giving and estimate of PSS) and standard deviation (estimating simultaneity bandwidth).