Identifying, Assessing, and Treating Dyslexia at School Developmental Psychopathology at School Series Editors: Stephen E. Brock, California State University, Sacramento, CA, USA Shane R. Jimerson, University of California, Santa Barbara, CA, USA Catherine Christo • John M. Davis Stephen E. Brock Identifying, Assessing, and Treating Dyslexia at School Catherine Christo John M. Davis California State University, Sacramento California State University, Department of Special Education, East Bay Rehabilitation School Psychology, 25800 Carlos Bee Blvd. & Deaf Studies Hayward CA 94542-3095 6000 J Street USA Sacramento CA 95819-6079 [email protected] USA [email protected] Stephen E. Brock California State University, Sacramento Department of Special Education, Rehabilitation School Psychology, & Deaf Studies 6000 J Street Sacramento CA 95819-6079 USA [email protected] ISBN: 978-0-387-88599-5 e-ISBN: 978-0-387-88600-8 DOI: 10.1007/978-0-387-88600-8 Library of Congress Control Number: 2008942044 © Springer Science+Business Media, LLC 2009 All rights reserved. This work may not be translated or copied in whole or in part without the written permission of the publisher (Springer Science+Business Media, LLC, 233 Spring Street, New York, NY 10013, USA), except for brief excerpts in connection with reviews or scholarly analysis. Use in connection with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed is forbidden. The use in this publication of trade names, trademarks, service marks, and similar terms, even if they are not identified as such, is not to be taken as an expression of opinion as to whether or not they are subject to proprietary rights. Printed on acid-free paper springer.com This book is dedicated to those children, families, and educational professionals who overcome the challenges associated with dyslexia. We hope that this book contributes to the well-being of both students and professionals who deal with this learning challenge. And to… the memory of my mother, Doris Maxine Jenkins Fuller. May all my deeds honor her memory. – CC … the ones I love. – JD Christine who inspires me and reminds me of the importance of my efforts. – SEB Acknowledgments As with any project of this magnitude, we believe it important to acknowledge the contributions of the individuals who have influenced our efforts. First, the authors are grateful for the collaboration with colleagues. Dr. Christo would like to particu- larly acknowledge Jack Davis for all the wonderful conversations about reading that serve to continually enlighten her and inspire her interest in the topic and those stu- dents who struggle with learning to read. Dr. Davis would like to give special thanks to all his friends and colleagues at the Raskob Institute for helping him learn what dyslexia is all about. He would like to give an extra special thanks to Mrs. Helen Nelson who managed to grind this information into his “semiresistant” brain. Dr. Brock would like to acknowledge Catherine Christo for her years of rewarding col- laboration and helpful consultations regarding children with reading disabilities and Jack Davis for his mentorship. Finally, we collectively acknowledge the many schol- ars who have contributed to the science that provides the foundation for the informa- tion presented in this book; previous and future scholarship is essential to continue to advance our understanding of the multifaceted influences and interventions asso- ciated with dyslexia. We would like to particularly acknowledge Carl Spring for sparking our interest with his pioneering work in the field of reading disabilities. vii Contents 1 Introduction and Overview. 1 Why School Professionals Should Read This Book . 1 School Success and Adult Outcomes. 2 Association with Juvenile Delinquency. 2 The Most Common Learning Disability Referral . 2 Importance of Early Identification and Intervention . 2 Changes in How School Professionals Respond to Dyslexia . 3 Defining Dyslexia . 4 History . 4 Current Conceptualizations . 5 Common Questions About Dyslexia . 7 Is Dyslexia Just the Low End of the Reading Skill Continuum? . 7 Are There Different Types of Dyslexia? . 9 Dyslexia and Special Education Eligibility . 10 Purpose and Plan of the Book . 12 2 Causes . 15 Changes in Perspective of the Etiology of Dyslexia . 15 Current Theoretical Views on the Etiology of Dyslexia. 16 Visual Processing Approaches. 16 Temporal Processing . 17 Phonological Core Deficit . 18 Dual Subtype Approaches . 18 Multiple Subtype Approaches . 20 Genetic, Neurobiological, and Environmental Contributions to the Understanding of Dyslexia . 21 Genetics . 21 Neurobiological Structures . 22 ix x Contents Environment. 23 Concluding Comments. 23 3 Prevalence and Associated Conditions. 25 Nonresponders . 26 Prevalence in Special Education . 27 Problems in Estimating Prevalence . 29 Prevalence and Gender. 29 Ethnicity. 30 Cross Linguistically . 31 Co-occurring Conditions . 32 Attention-Deficit/Hyperactivity Disorder . 32 Dyscalculia. 33 Specific Language Impairment . 34 Concluding Comments. 35 4 Case Finding and Screening . 37 Issues in Case Finding and Screening . 37 Identifying Children Prior to School Entry . 40 Family History . 40 Language Development . 42 Otitis Media . 45 Preschool Screening Batteries . 45 Kindergarten Screening . 48 Visual Processing. 49 Phonological Awareness . 49 Vocabulary . 50 Naming Speed Tasks . 50 Early Literacy Skills . 51 Screening as a Dynamic Activity. 51 Screening Measures . 52 Summary and Concluding Comments . 56 5 Diagnostic Assessment . 59 Reading Disorder . 60 Diagnostic Criteria. 60 Symptom Onset . 60 Developmental Course. 61 Associated Features . 61 Gender-Related Issues . 62 Differential Diagnosis . 62 Disorder of Written Expression . 62 Symptom Onset . 63 Contents xi Developmental Course. 63 Associated Features . 64 Gender-Related Features . 64 Differential Diagnosis . 64 Learning Disorder Not Otherwise Specified . 65 Developmental, Health, and Family History . 65 Perinatal Risk Factors . 65 Developmental Milestones. 72 Medical and Diagnostic History . 72 Family History . 72 Indirect Assessment . 73 Concluding Comments. 74 6 Psychoeducational Assessment . 75 Special Education.