Document Type : Original Articles

Authors

• Navid Mirzakhany ¹
• Sara Izadi Najafabadi ²
• Vahid Nejati ³
• Zahra Pashazadeh ¹
• Leila Shokoohandeh ⁴
• Masumeh Pirooz ⁵

¹ Lecturer, Department of Occupational Therapy, School of Rehabilitation Science, Shahid Beheshti University of Medical Science, Tehran, Iran

² Lecturer, Department of Occupational Therapy, School of Rehabilitation Science, Isfahan University of Medical Science, Isfahan, Iran

³ Assisstant Professor, Department of Psychology, School of Psychology, Shahid Beheshti University of Medical Science, Tehran, Iran

⁴ MSc, Department of Psychology, School of Psychology, Isfahan University, Isfahan, Iran

⁵ MSc Student in Psychology, Department of Psychology, School of Psychology, Isfahan University, Isfahan, Iran

Abstract

Introduction: Autism Spectrum Disorders (ASDs) are associated with various abnormalities of cortical areas resulting in motor learning deficits. Motor learning can be categorized into two main types: implicit motor learning and explicit motor learning. The main goals of this study was to investigate the possible differences between implicit and explicit motor learning in children with high functioning autism including those with Asperger Syndromes and a matched group of typical children and to evaluate the extent of learning consolidation in these two groups after 24 hours. Materials and Methods: 30 boys with autism spectrum disorder, diagnosed via ASSQ, and a matched group of 32 typical boys were recruited from elementary schools of Najaf Abad, Isfahan, Iran, and then were compared with each other. At the first day of the study, participants in both groups performed a serial reaction time task with 10 blocks by the right hand. A similar task with 4 blocks and by the same hand was performed after 24 hours. Repeated measure ANOVA was conducted for the statistical analysis of the data using SPSS 19. Results: Concerning explicit motor learning, the two study groups showed a significant difference which implicated an explicit learning deficit in the subjects with ASD (P = 0.009). Results also indicated no significant difference in implicit learning between these two group (P = 0.385). Intact implicit consolidation (P = 0.160) and deficit in explicit consolidation (P = 0.046) was also observed in the ASD group. Conclusion: Deficits in explicit motor learning and consolidation among subjects with ASD may be due to left hemisphere dysfunction which is specialized for motor learning. Since explicit consolidation is sleep-dependant and children with ASD usually suffer from sleep disorders, deficit in explicit consolidation was expectable. Intact implicit learning and consolidation can be attributed to the effect that right hemisphere has on implicit motor learning. Keywords: Motor learning, Explicit learning, Implicit learning, High-functioning autism, Asperger, Sleep disorder, Serial reaction time task, Consolidation