Figure 5. A) Proportion of synchrony judgments per group as a function
of stimulus onset asynchrony (SOA), relative to the modality order of
the preceding trial (collapsed across congruency conditions). Here,
negative SOAs indicate that the voice was leading the lip movements, and
vice versa. B) Point of subjective simultaneity (PSS) per group relative
to the modality order on the preceding trial. C) Magnitude of
recalibration effect (i.e., change in PSS between preceding modality
orders) per group relative to age (in bins of 10 years). The error-bars
reflect the standard error of the mean.
We conducted a repeated measures ANOVA on the mean PSS with previous
modality order as a within subjects variable, group as a between
subjects variable, and age as a covariate. We found a significant main
effect of modality order (F (1,865)=13.823,p <.001), such that the PSS was smaller when audition
led in the previous trial than when vision led, as Figure 5b
illustrates. Rapid temporal recalibration did not differ between groups,
as the modality order x group interaction failed to reach significance
(F (1,865)=1.968, p =.161). Autistic participants showed a
larger average PSS (240 ms) than non-autistic participants (190 ms)
overall (F (1,865)=13.866, p <.001), reflecting a
preference for a greater visual lead. Age did not significantly affect
the magnitude of rapid temporal recalibration, as it did not interact
with previous modality order (F (1,865)=2.624, p =.106; see
Figure 5c). However, older participants did have a higher overall PSS
(F (1,865)=51.770, p <.001). The mean PSS for
participants above the median age was 249 ms, compared to a mean of 188
ms for those below the median age.