As described above, the rubber-hand illusion should be
expected to trigger differences in expected precisions of visual,
tactile and proprioceptive sensory input. Our previous study of this
illusion (Paton et al., 2012) compared a clinical ASD group with
healthy controls and found differences in proprioception and
motor parameters on a reach task. Following the results of this
study, we expect that participants will experience the typical
subjective effects of the illusion (e.g., that touch is mislocated to
the rubber hand) regardless of their level of ASD-like traits, and
thus rate the strength of these effects, as assessed via questionnaire,
stronger during synchronous than asynchronous stimulation.
We further predict that individuals with ASD-like traits will
show less sensitivity to the presence of the illusion in their
perceived arm position than individuals low on ASD-like traits
(i.e., less of a difference in proprioceptive drift between synchronous
and asynchronous stimulation conditions). This hypothesis is
based on the notion of lower sensitivity to state-dependent
uncertainty in individuals with ASD-like traits, and coheres with
the previous finding of more accurate proprioception in individuals
with ASD compared to controls (Paton et al., 2012).