The Preeminence of Phonologically Based Skills in Learning to Read

This latter point alludes to another disparity for which there is now some research evidence, specifically, that linguistic coding abilities themselves may be weighted differently as determinants of skill in beginning reading. Isabelle Liberman and her associates at the Haskins Laboratories have long contended that phonologically based skills, such as phoneme segmentation and alphabetic mapping, are the primary determinants of initial success in word identification, and there is considerable evidence that poor readers tend to be deficient in both areas (Bradley & Bryant, 1983; Liberman & Shankweiler, 1979; Shankweiler & Liberman, 1989; Vellutino, 1979; Vellutino & Scanlon, 1987). Their contention rests on the assumption that adequate facility in these areas is a prerequisite for success in beginning reading, given the heavy load on memory inherent in any alphabetically based orthography, and given the highly abstract way in which written English, in particular, often represents the language (see Liberman, 1983, for an excellent discussion of these notions).