Brief Report: Can You See What is Not There? Low-level Auditory–visual Integration in Autism Spectrum Disorder

Abstract

Patients diagnosed with Autism Spectrum Disorder, show impaired integration of information across different senses. The processing-level from which this impairment originates, however, remains unclear. We investigated low-level integration of auditory and visual stimuli in subjects with Autism Spectrum Disorder. High-functioning adult subjects with Autism Spectrum Disorder as well as age-and IQ-matched adults were tested using a task that evokes illusory visual stimuli, by presenting sounds concurrently with visual flashes. In both groups the number of sounds presented significantly affected the number of flashes perceived, yet there was no difference between groups. This finding implicates that any problems arising from integrating auditory and visual information must stem from higher processing stages in high-functioning adults with Autism Spectrum Disorder.

Multisensory Integration of Low-level Information in Autism Spectrum Disorder: Measuring Susceptibility to the Flash-Beep Illusion

“…Additionally, the differences in results across the current study and those of van der Smagt et al (2007) may have been due to a number of factors related to our methods and participant sample (e.g., mean FSIQ, diagnostic criteria, age). The participants in the current study spanned adolescence and adulthood, and included greater age variation than had been used in the study by van der Smagt et al (2007).…”

“…Specifically, the ASD group may have perceived the two flashes as 1 due to their enlarged TBW, but the TD group may have shown less of an effect due to the enlarged interstimulus gap. Similarly, in another study by van der Smagt et al (2007), an interstimulus interval of 50 ms was also used. Again, the enlarged interval in the current study may have influenced the difference in susceptibility to the fusion illusion between both groups.…”

“…The participants in the current study spanned adolescence and adulthood, and included greater age variation than had been used in the study by van der Smagt et al (2007). Given that younger TD children have been found to have greater susceptibility to the flash beep illusion that adults (Innes-Brown et al 2011), it is possible that the current results of greater susceptibility to the fusion illusion may be related to the larger age variation in the sample.…”

“…When the presence of the fusion and fission illusions was examined in a group of high-functioning adults with ASD, it was found that the ASD group was susceptible to both illusions to a similar degree as a TD comparison group, thereby suggesting that the ASD group was showing typical MSI (van der Smagt et al 2007). In another study using various tasks to evaluate MSI in a sample of highfunctioning adults with ASD, the sound-induced flash illusion was tested (Keane et al 2010).…”

“…While some research has been conducted using the flash-beep paradigm in ASD, these studies have either only studied high-functioning individuals with elevated IQ's, examined one of the two flash-beep illusions (i.e., only fission) or have only studied one age group (Foss-Feig et al 2010;Keane et al 2010;Stevenson et al 2014b;van der Smagt et al 2007). Furthermore, studies using similar low-level paradigms (e.g., visual search) have yielded inconsistent results (de BoerSchellekens et al 2013;Collignon et al 2013).…”