Reading Disorders By: Larry Burd, Ph.D. Director, North Dakota Fetal Alcohol Syndrome Center University of North Dakota, School of Medicine and Health Sciences Grand Forks, ND

Many of the slides in this presentation are from the work of Pelli et al Nature (423) 752-756; 2003 or Wilson et al Nature (423) 696-697; 2003.

By age 25 the average person has read 100,000,000 words.

Efficiency Level in Reading 1 n = number of letters in word

1,000 Human 100 Energy (relative to noise) Ideal 10 1 Word Length (letters) 10

0.1 Efficiency 0.01 1 10 Word Length (letters)

5 most common 3 letter words: The And Was For His

Least frequent word “his” is encountered: 100 times per hour 400,000 times per decade if reading 1 hour a day

Letter Recognition All or not very well phonemena

Word Effect Coin C Join J

Comprehension Decoding impairs comprehension Comprehension improves decoding

Rset Pclae Rghit Ltteer Lsat Tihng Iprmoetnt Bcuseae porbelm Raed Rscheearch Elingsh Mese Still Lteter Ervey Word wlohe

Comprehension Improves Decoding Skills Aoccdrnig to rscheearch at an Elingsh uinervtisy, it deosn’t mttaer in what oredr the ltteers in a word are, the olny iprometnt tihng is that frist and lsat ltteer is at the rghit pclae. The rset can be a toatl mses and you can still raed it wouthit porbelm. This is bcuseae we do not raed ervey lteter by istlef but the word as a wlohe.

Reading Skills Progression Signs Alphabet Letter Sounds Phonics Words Careful Reding Comprehension Rapid Reading Skipping Context Context and Skipping

Reversals are Frequent p/d p/b q/g m/w was/saw on/no

Rarely 6/9 2/6 3/8