Dylexia in children and young adults: three independent neuropsychological syndromes.
In an attempt to delineate causal factors in dyslexia, 113 children and young adults (age-range eight to 18 years) were divided into three groups: those with brain damage who could read (n=31), those with brain damage who were dyslexic (n=53), and those without brain damage who were dyslexic (n=29).  A battery of neuropsychological tests was presented to each participant.  No significant differences were found between the two dyslexic groups.  Three syndromes--language disorder, articulation and graphomotor dysco-ordination, and visuo-perceptual disorder--were found among the great majority of those with dyslexia.  The results support a model of dyslexia as being caused by multiple independent defects in higher cortical functioning, as opposed to the theory of a single causal defect.  A clinical description of each syndrome is given and models of dyslexia are discussed.  The authors stress the desirability of including brain-damaged readers as a control group in any future study on causal factors in dyslexia.
D000293:Adolescent; D001037:Aphasia / Q000150:complications; D001925:Brain Damage, Chronic / Q000150:complications*; D002648:Child; D004410:Dyslexia / Q000145:classification* / Q000209:etiology; D006801:Humans; D008962:Models, Theoretical; D009048:Motor Skills; D009460:Neurologic Examination; D011581:Psychological Tests; D013064:Speech Disorders / Q000150:complications; D014786:Vision Disorders / Q000150:complications; D014796:Visual Perception