[Neuropsychological differentiation of specific dyslexia in children].

An approach to dyslexia is substantiated in terms of a multilevel organization of written speech (gnostico-praxical and symbolical levels). Two dyslexia forms were differentiated in a neuropsychological investigation of 32 children. First had a selective written speech disorder based upon a visual perception deficit. Second type of dyslexia was caused by a distortion of acoustic symbols of the language which was evident not only in writing and reading disorders but also in impaired notional thinking (language acoustic coding disorder). This approach provides a basis for an adequate pedagogical correction of dyslexia.