Two realizations prompted research on reading at Haskins in the 1960s. First, literacy skills stand in stark contrast to the innate basis of spoken language abilities. Whereas people everywhere learn to talk and do so proficiently, to this day the majority of the world's population remains illiterate. Even in the U.S. with widespread educational opportunities, large proportions of students fail to become skilled readers. Researchers at Haskins began to ask why learning to read and write is so much more challenging than learning to perceive speech and to produce it. The second impetus for research on reading hinged on the discoveries at the Labs of the coarticulatory nature of speech production. In speech production talkers overlap the production of speech sounds temporally. A consequence is that the acoustic speech signal does not have segments in it that correspond to the consonants and vowels (phonemes) of the spoken language that letters of the alphabet represent. This makes it difficult for children to discover the individual phonemes represented in our alphabetic writing system. Because letters and letter patterns in written English correspond with individual speech sounds, the child or adult learning to read has to become aware of those individual speech sounds in spoken words in order to understand how the writing system works and to master the patterns. To skilled readers, this insight seems trivially easy, yet research at the Labs proved otherwise. Young children focus on the meanings of words and find it much more difficult to become aware of the phonemes making up those words. Importantly, those youngsters who in the early grades of school still are not fully aware of the individual speech sounds in spoken words are the ones struggling with learning to read. For example, the student who is not aware that the final sound in 'dog' is 'g' will not grasp why it is spelled with the letter g. Subsequent studies found that limitations in phoneme awareness are one of the hallmarks of reading weaknesses at any age, even for adults.
The finding of the importance of phoneme awareness for learning to read led to numerous areas of investigation on phoneme awareness and other components of reading. Some of these, together with practical applications, are briefly discussed below:
1) Is it possible to predict which young children are at-risk for reading problems? Yes, weaknesses in phoneme awareness, letter knowledge and certain language abilities turn out to be strong predictors of subsequent difficulties learning to read.
2) Is early intervention possible? Absolutely. Numerous studies at Haskins Labs and elsewhere have demonstrated that phoneme awareness concepts can be taught and that doing so reduces the risk of reading difficulties. When this instruction is combined with teaching letter-sound patterns, children benefit even more.
3) Do individuals with reading disabilities have other sources of difficulty? A second hallmark of the person with low levels of literacy is poor word recognition skills. The decoding skills (i.e., abilities to sound out unfamiliar words) in the vast majority of impaired readers (and beginning readers) are slow and/or inaccurate. This continues to be true for most older poor readers (particularly if they haven't received appropriate intervention), although a portion of older less-skilled readers have problems limited to comprehension difficulties. An implication of these findings is that for individuals at all ages with reading difficulties, it is important to carefully assess the component skills of reading (phoneme awareness, decoding, word recognition, fluency, comprehension) in order to identify and subsequently treat their particular areas of weakness.
4) Does the kind of instruction make a difference? Research by Haskins investigators and other scientists converges to indicate that direct, systematic instruction in kindergarten and the early grades is optimal. When students are explicitly taught phoneme awareness, decoding and other aspects of the writing system, the percentage of students having difficulty learning to read is greatly reduced when compared with the percentage of struggling students taught with less explicit methods.
5) Why do some children have a harder time acquiring phoneme awareness and learning to read? Part of the explanation for individual variation in reading success is genetic. The spoken language abilities centrally related to reading development have a biological basis and appear to be normally distributed in the population. The relevant language abilities pertain to the phonological component of language: in addition to weaknesses in phoneme awareness, differences in the use of phonological codes to store and use language have been documented. For example, individuals with dyslexia often have more difficulty spelling words or correctly pronouncing newly learned words in their spoken vocabulary. In families with a history of reading difficulty, early screening for language and reading difficulties will allow children at-risk to be detected and given effective intervention. Reversal of letters, such as writing 'bab' for 'dad' turns out not to be a diagnostic feature of dyslexia, but a common occurrence for beginning readers and spellers.
A second factor affecting ease in learning to read appears to be environmental. Early childhood activities such as songs and word games (e.g., rhyming; identifying the first sound in words) enhance awareness of the sounds in words and help the child move toward full appreciation of the phonemic composition of words. Families, as well as preschool programs, that deliberately incorporate such activities and foster letter knowledge increase the likelihood of reading success in children. Building enthusiasm for books, appreciation of text structures, and vocabulary knowledge are also important, especially for later reading achievement, but less centrally related to acquiring the necessary skills for early reading success. Children from disadvantaged backgrounds, known to be at risk for reading failure, tend to enter school significantly behind their age-mates in phonological awareness, in knowledge of the alphabet, and in vocabulary. The implications for pre-school interventions are increasingly recognized by federal, state and local agencies.