 The ODH accounted for the cognitive processing balance between letter decoding and the processing of larger text clusters as a function of the degree of isomorphism between a writing system's letters and phonemes.By the 1990s, he was a member of teams (led by Bennett and Sally Shaywitz at Yale and Ken Pugh at Yale and Haskins) that utilized brain-scan data from MRI, fMRI, and MRS to study reading.That work, together with the work of many other researchers, established the outlines of the brain's mechanisms involved in processing printed words.