Poster D22, Monday, March 26, 8:00-10:00 am, Exhibit Hall C
Reliability of evoked responses varies as a function of autistic traits in healthy adults
Meghan Puglia1, Jessica Connelly1, James Morris1; 1University of Virginia
Evoked neural responses show greater variability among individuals with autism compared to neurotypical controls (Dinstein et al., 2012; Milne, 2011). As it is increasingly understood that autistic traits are expressed on a continuum in the general population, we examine whether variability in evoked response is also associated with the occurrence of autistic traits in healthy adults. Eighty-six neurotypical adults (49 males) passively viewed alternating blocks of point-light displays of biological or random motion while undergoing fMRI. Autistic traits were assessed with the Autism Spectrum Quotient Questionnaire (AQ) (Baron-Cohen et al., 2001). We first performed an independent component analysis (ICA) to identify regions of interest (ROIs) with a model-free, data-driven approach, resulting in 12 unique clusters encompassing posterior and prefrontal regions including bilateral superior temporal sulcus. Neural variability was quantified as the standard deviation of each time point within each individual’s peristimulus timecourse for each ROI and stimulus type. AQ score and neural variability were significantly associated (all p-values <.0001). For the biological condition, variability of neural response across ROIs accounted for 5 to 28% of variance in autistic traits. For the random condition, variability of neural response across ROIs accounted for 7 to 59% of variance in autistic traits. These results demonstrate that healthy adults with a high occurrence of autistic traits show a similarly unreliable neural response to that seen in clinical populations. Neural variability has been associated with cognitive and developmental processes (Misić, et al., 2010), and may therefore represent a useful metric for informing differential neurodevelopmental trajectories.
Topic Area: EMOTION & SOCIAL: Person perception