This NINDS Mentored Patient-Oriented Research Career Development Award (K23) entitled "Developmental Phonological Dyslexia: Neural Mechanisms" proposes to develop the candidate's competence in patient care and research in the field of developmental cognitive neuroscience, with a focused application of recent advances from this field to the understanding and treatment of developmental disorders of cognition. The candidate will pursue coursework in clinical effectiveness, ethics and neuroimaging, clinical duties involving children and young adults with learning disorders, and research. The research component will focus on mechanisms underlying compensation for the non-fluent, inaccurate reading seen in dyslexic readers. The work will take place at Boston University, the MGH/MIT/HMS Athinoula A. Martinos Imaging Center, the Children's Hospital Boston, and the Harvard School of Public Health. Despite the fact that behavioral observations suggest that developmental phonological dyslexic readers rely on whole word (lexical), rather than phonological (sub-lexical) processing, most neuroimaging studies have concentrated on the dysfunction of the phonological processing system rather than on comparing the functional roles of the 2 word processing systems in dyslexic and normal readers. In the proposed study, participants, during magnetoencephalography (MEG) recording, will judge whether 2 sequential visually presented words or pronounceable non-words rhyme. The visual rhyme stimuli will be specifically designed to activate only 1 of the 2 classically recognized word processing systems. Using anatomically-constrained MEG each system will be tested separately, as well as the dynamic interaction between them, in 3 separate experiments carried out in normal and dyslexic readers. The subgroup of phonologically dyslexic readers will be identified from a larger group of poor readers using specific tests of reading ability and matched to normal readers in terms of age, sex and a non-verbal measure of general intelligence. The proposed research project and educational components will allow the candidate to improve his skills as a clinical investigator and to gain the experience and knowledge for influencing public health and educational policy. In addition, the insight provided by this research will help guide the development of improved methods of diagnosis, rehabilitation, treatment and long-term monitoring of individuals with developmental cognitive disorders.