Dyslexia is a learning disorder that impairs reading and spelling abilities. It affects 5-17% of the population and can be developmental, beginning in childhood, or acquired through brain damage. Core impaired processes include phonological reading, phonological coding, lexical access, and working memory. Symptoms include errors like omissions, substitutions, inversions, and additions in reading and spelling. Diagnosis involves reading and spelling skills being 1.5-2 standard deviations below expectations based on age, intelligence, and education. Dyslexia impacts 15-50 million Americans and can affect academic and career success due to reliance on reading skills. Theories propose both environmental and biological factors, with neuropsychological research finding dysfunction in

1. Sean Weigold Ferguson Cognitive Psychology Rollins College Dyslexia

2. “ Accurate and fluent word reading and/or spelling develops very incompletely or with great difficulty” Affects between 5% and 17% of the population Overview (McCandliss and Noble, 2003)

3. Types Developmental: Begins in childhood and usually continues throughout adulthood Acquired: Often from traumatic brain damage

4. Impaired Processes Phonological reading: Words in isolation Phonological coding: Recalling confusing strings of phonemes Lexical access: Retrieving phonemes from long-term memory Working memory: Remembering strings of phonemes that are sometimes confusing.

5. Symptoms Reading and spelling: Omissions Substitutions Inversions Additions Often accompanied by dysfunction in: Fine motor coordination Visual discrimination Auditory segmenting difficulty (Cicchetti and Cohen, 2006)

6. Diagnosis Reading and spelling skills significantly below performance expectations for age, intelligence, and education level (1.5 to 2 standard deviations). However, IQ may be inaccurately measured in dyslexics. (Cicchetti & Cohen, 2006; McCandliss & Noble, 2003)

7. Implications Affects between 15 and 50 million Americans. Culture places high value on reading. Scholastic success often dependent on reading skills. Many skilled jobs require employees to be literate. (McCandliss and Noble, 2003)

8. Theories Environmental: Interventions can be effective Biological: Abnormalities in chromosomes 3, 6, and 15 (Paracchini, Scerri, and Monaco 2007)

9. Neuropsychology Dysfunction in: Left perisylvian area involving the superior temporal gyrus; involved in phonological processing. Leads to underdevelopment of: Left occipito-temporal extrastriate visual system near the middle portion of the fusiform gyrus; involved in automatic processing of visual word form perception in skilled adult readers. (McCandliss and Noble, 2003)

10. Surrounding Structures I created this figure using an image by the University of Western Ontario Psychology Department

11. Specific Structures Original image from McCandliss and Noble, (2003)

12. What is it Like? Video by Coventry University TV

13. Questions? Sean Weigold Ferguson [email_address] 407-584-7326 This presentation is available online at www.SlideShare.net/SeanWF It is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License

14. References Cicchetti, D., & Cohen, D. J. (2006). Developmental psychopathology . John Wiley and Sons. McCandliss, B. D., & Noble, K. G. (2003). The development of reading impairment: A cognitive neuroscience model. Mental Retardation and Developmental Disabilities Research Reviews , 9(3), 196-205. Paracchini, S., Scerri, T., & Monaco, A. P. (2007). The genetic lexicon of dyslexia. Annual Review of Genomes and Human Genetics , 8, 57-79. University of Western Ontario Psychology Department (2005). Temporal lobe sulci [Photograph], Retrieved April 24, 2010, from: http://psychology.uwo.ca/fmri4newbies/Images/temporal_lobe_sulci.jpg