Significant controversies have arisen over the developmental trajectory for the perception of global motion. Studies diverge on the age at which it becomes adult-like, with estimates ranging from as young as 3 years to as old as 16. In this article, we review these apparently conflicting results and suggest a potentially unifying hypothesis that may also account for the contradictory literature in neurodevelopmental disorders, such as Autism Spectrum Disorder (ASD). We also discuss the extent to which patterned visual input during this period is necessary for the later development of motion perception. We conclude by addressing recent studies directly comparing different types of motion integration, both in typical and atypical development, and suggest areas ripe for future research.

Perceptual atypicalities are a widely acknowledged but poorly understood feature of autism. We demonstrate here a striking violation of one of the most adaptive psychophysical computations – Weber’s law – in high-functioning individuals with autism. JNDs based on the best-fitting psychometric functions were measured for size visual judgments (Exp. 1), weight haptic discrimination (Exp. 2), and illusive perception of weight (brightness-weight illusion; Exp. 3). Results for the typically developed group confirmed Weber’s law, demonstrating a linear increase in JNDs with intensity, resulting in constant fractions across intensities. The results for the ASD, in contrast, showed no scaling of JNDs with intensity; instead, fractions decreased linearly with intensity. In striking contrast to its consistency in typical perception, Weber’s law does not hold for visual and haptic perception in autism. These robust modulations in psychophysical computations, demonstrated for different domains of perception, suggest a modality-independent, low-level mechanism driving altered perception in autism.

Emerging accounts of autism suggest that flexible and broadly tuned perceptual representations, presumably resulting from reduced specialization, may underlie atypical perception. Here, we examined the other-race effect (ORE) to study face processing specialization arising from specific experience with own-race faces. Face discrimination was tested for own-and other-race faces in typically developed individuals and in individuals with autism spectrum disorder (ASD). For each race, faces were morphed to vary discrimination difficulty, and orientation was manipulated to examine inversion effects. The ASD group displayed overall lower sensitivity and reduced inversion effects in processing faces. Importantly, the processing advantage for own-race faces was substantially smaller in this group, resulting specifically from the reduced specialization for the own-race faces. Moreover, the typical larger inversion effect for Caucasian faces was not observed in the ASD group; sensitivity to orientation was smaller and equivalent for the two face races. These more broadly tuned representations in autism may account for the overall weaker representations of faces and suggest, more broadly, that a failure in perceptual specialization may underlie atypical perception in autism.

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