Integrating RTI with Cognitive Neuropsychology: A Scientific Approach to Reading by Steven Feifer, D. Ed. and Douglas Della Toffalo, Ph.D. Chapter 5 Subtypes of Dyslexia. The subtypes are: Dysphonetic Dyslexia which is the inability to learn letter-sound correspondance. The skills involved are Phonemic Awareness and phonological processing. The parts of the brain which are involved in this are the following: Heschl’s Gyrus (auditory perception and discrimination); Superior Temporal Gyrus(modulating the 44 phonemes of English); Supramarginal Gyrus (cross modal association for spatial and positioning of sounds); Angular Gyrus (cross modal mapping symbold to sounds); Inferior Frontal Gyrus( inner articulation) and Dorsal Stream (all of the above which phonologically assemble a word). Younger learners do best with a highly structured and explicit phonological training. Surface Dyslexia is where students can sound out words but cannot recognize words in print. A third tpe is Mixed Dyslexia which the most severe. These students need an very intense phonics type program.