Motion perception and autistic spectrum disorder: A review

This is a reprint of an article printed in the February – April issue (2005) of Cahiers de Psychologie Cognitive / Current Psychology of Cognition, volume 23 (1 – 2), pp 3 – 33. Motion perception and autistic spectrum disorder 2 Abstract Recent evidence has indicated that some children with autistic spectrum disorder (ASD) show reduced ability to detect visual motion. The data suggest that this impairment is present in children with a range of autistic spectrum diagnoses, but not present in all children diagnosed with ASD. The occurrence of abnormal motion perception in children with ASD has led to speculation regarding the root of this impairment. Hypotheses regarding reduced sensitivity of the visual magnocellular system / cortical dorsal stream (Milne et al., 2002; Spencer et al., 2000) and reduced neuronal integration (Bertone et al., 2003), will be discussed in this review. Clinical implications of the impairment, such as the degree to which motion perception may be related to diagnostic criteria and /or symptom severity in ASD, and the relationship between abnormal motion perception in autistic spectrum, and other, non-autistic spectrum developmental disorders will also be discussed. The conclusion is drawn that more research should be carried out including larger samples of participants, and that in future studies researchers should provide details of the variability of performance in their data, and investigate relationships between motion perception, diagnostic criteria, symptom severity and other potential correlates which, it is hoped will lead to further understanding of the implications of abnormal motion perception in ASD. Motion perception and autistic spectrum disorder 3 Autistic spectrum disorder (ASD) is a family of pervasive developmental disorders, usually diagnosed in childhood. Within the autistic spectrum are autistic disorder, diagnosed on the basis of impairments in social interaction, communication, and repetitive, stereotyped patterns of behaviour (American Psychiatric Association, 1994); Asperger's disorder, which is popularly characterised as a less severe form of autistic disorder but in actuality is diagnosed on the basis of impairment of social interaction, accompanied by repetitive, stereotyped behaviour, but without a significant impairment in communication (American Psychiatric Association, 1994); and pervasive developmental disorder not otherwise specified (PPD-NOS), which is diagnosed on the basis of impairment in social interaction or communication skills, or when stereotyped behaviours are present, but the full criteria for a specific pervasive developmental disorder are not met. This category includes atypical autism which is diagnosed when presentations do not meet the criteria …