Abstract
In this longitudinal, multiple case study, I describe and compare the early development, instructional history, repeated administrations of a test battery, and response to instructional intervention for seven boys (in third to fifth grade at time of intervention), who were brain imaged prior to intervention and found to differ from controls in brain chemical activation during a phonological task. The instructional intervention was phonologically driven reading instruction in a science/reading workshop. At follow-up, phonological skills (phonological manipulation, phonological memory, and phonological decoding) had improved compared to initial assessment, but the boys were better at silent reading comprehension than oral reading, and had rate impairments and considerable difficulties with writing skills (handwriting automaticity, spelling, and speed of composing). Based on recent research on the genetic phenotype (language markers) and on early intervention, a case is made that dyslexia should be diagnosed early in schooling, on the basis of markers for deficient language processes and response to early intervention, so that appropriate instruction can be instituted early and continued throughout schooling as long as necessary. Dyslexia is a developmental disorder that manifests in different ways at different developmental stages, initially as difficulty in learning letters and letter-sound correspondence, next in learning to read words accurately, and finally in impaired reading rate and written expression skills (handwriting automaticity, spelling, and compositional fluency).