Regardless of the precise source, increased EEG variability in those with ASD is evidence of increased intrinsic neural “noise” (Sannita, 2006). Increased neural noise in ASD has been predicted by a number of authors (see Simmons et al., 2009), however, the data reported here represent the first empirical demonstration of increased neural noise in ASD. Increased neural noise has the potential to influence behavior in a variety of ways, and its impact on different levels of function, e.g., perception, cognition, and behavior, may not be consistent. Whilst an increased noise-to-signal ratio leads to reduced perceptual sensitivity in many cases, one type of noise – stochastic resonance – can amplify a signal, leading to increased sensitivity. Increased levels of neural noise have therefore been discussed in relation to atypical perception in ASD, and offered as a parsimonious explanation of data in which those with ASD show both hyper- and hypo-reactivity to perceptual stimuli and enhanced and impaired perceptual sensitivity measured with psychophysical tasks (Simmons et al., 2009).
