Implicit motor learning deficits in dyslexic adults

• Published in: Neuropsychologia Vol. 44; no. 5; pp. 795 - 798
• Main Authors: Stoodley, Catherine J., Harrison, Edward P.D., Stein, John F.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 2006; Elsevier Science
• Subjects: Adult; Analysis of Variance; Biological and medical sciences; Brain; Case-Control Studies; Cerebellum; Developmental dyslexia; Disorders of higher nervous function. Focal brain diseases. Central vestibular syndrome and deafness. Brain stem syndromes; Dyslexia; Dyslexia - complications; Dyslexia - physiopathology; Female; Humans; Learning Disabilities; Learning Disorders - etiology; Male; Medical sciences; Nervous system (semeiology, syndromes); Neurology; Perceptual Motor Skills; Psychomotor Performance - physiology; Reaction Time - physiology; Response Time; Serial reaction time task; Developmental dyslexia; Cerebellum; Serial reaction time task; Human; Nervous system diseases; Reading disorder; Cognition; Motor learning; Language disorder; Communication disorder; Acquisition process; Learning disability; Serial reaction time; Adult; Dyslexia; Implicit learning; Neurological disorder
• ISSN: 0028-3932; 1873-3514
• DOI: 10.1016/j.neuropsychologia.2005.07.009

Children with developmental dyslexia fail to develop age-appropriate reading skills despite adequate intelligence and education. It has been suggested that dyslexics’ various literacy, sensory and motor difficulties may be related to impaired cerebellar function. As the cerebellum is involved in motor learning, we measured serial reaction time performance in 40 adults (21 controls, 19 dyslexics). Dyslexic subjects performed comparably to controls during the randomly-ordered reaction time blocks, indicating that the dyslexics were as able as controls to make appropriate stimulus-response associations. However, the dyslexics failed to show the reaction time reduction that the control group showed during the repeated sequences ( p = 0.018) and there was a significant group by condition effect when comparing the last two blocks of the sequence condition with the first two blocks of the final random condition ( p = 0.008). Furthermore, there was a significant difference between good and poor readers on the degree of learning during the task ( p = 0.015). This suggests that some dyslexics may suffer from an implicit motor learning deficit, which could generalize to non-motor learning.