General movements in infants with autism spectrum disorders

Abstract

General movements (GMs) are a distinct movement pattern carried out spontaneously without external stimulation and seen in fetuses of 9 weeks gestational age till 21 weeks postterm. GMs are helpful in the early diagnosis of an impaired central nervous system and the specific prediction of later neurological deficits. Autism spectrum disorder (ASD) is a neurodevelopmental disorder involving a life-long deficit in several aspects of the social and communicative behavior. Recently there appeared studies proving that children with ASD demonstrate disorders of motor development. To detect whether abnormalities in spontaneous motor activity can be observed already in the first months of life in infants with ASD. A retrospective study was performed by analyzing the family videos provided by parents of 20 children (male 17, female 3) later diagnosed as ASD. Home videos provided by parents of a control group of healthy children (n=20; male 10, female 10) matched for age with the ASD subjects and recorded in similar conditions were also analysed. In total 70 sequences were studied. Two independent observers, blind of the infants' outcome (ASD or normal), assessed the cases applying a global and a more detailed assessment of GMs. Hence, the age-specific GM pattern (normal or abnormal) as well as motor optimality scores were determined for each video sequence. Cohen kappa was 0.614. During the writhing movement period 70.0% sequences of infants with ASD showed poor repertoire GMs. In the control group, poor repertoire GMs were only seen in 12.5% of the sequences. In the fidgety movement period 20.8% of sequences were assessed as absent fidgety movements, 29.2% as abnormal fidgety movements. The large majority of the videos for the control cases were scored as normal (88.9%), 11.1% had no fidgety movements. According to the Mann-Whitney U test there were significant differences between the ASD and the control groups' optimality scores. The optimality scores were lower in the ASD group. The reduced optimality scores were mainly due to a lack of variable sequences, amplitude and speed of writhing GMs and an altered quality of fidgety and other spontaneous movements in the ASD group. Infants with ASD had more often poor repertoire writhing GMs as well as abnormal or absent fidgety movements than control infants. These data encourage further studies involving a larger number of family videos.