Reading Skill and Components of Word Knowledge AFfect Eye Movements During Reading

Four studies were conducted to examine the effects of individual skill differences among adult readers, as well as the effects of the quality of their lexical knowledge, on eye movements during reading. Study 1 defined dimensions of adult reader variability via a factor analysis of a database of adult reading assessments. Five dimensions emerged from the analysis reflecting: (1) speed/reading experience (expertise), (2) sublexical skills, (3) accuracy, (4) learning/memory, and (5) amount of ``casual reading'. Study 2 examined the effects of each of the dimensions of variability on eye movements during paragraph reading. Expert readers read words more quickly, especially less frequent words. Readers with good sublexical skills exhibited faster reading on early fixations, especially for more frequent words. These results suggest that individual differences in reading may be largely based on differences in the quality of lexical representations, with experienced readers having more knowledge of low frequency words, and readers with good sublexical skills having more unitized representations of frequent words. Study 3 employed a training paradigm in order to control the quality of lexical knowledge readers had along orthographic, phonological, and meaning dimensions. Orthographic and phonological training affected first pass reading measures, and phonological and meaning training affected second pass measures. The direction and strength of the training effects were mediated by individual differences between readers in their ability to learn from experiences. Study 4 examined the effects of components of word knowledge on eye movements by testing readers' orthographic, phonological, and meaning knowledge of words they read in context. Results confirmed the results of Study 3, with orthographic and phonological knowledge affecting early fixations, and meaning knowledge affecting re-reading. Studies 3 and 4 also showed a pattern of faster first fixations with more rereading for the words with the list familiar forms. Results from the set of experiments show that each component of word knowledge affects eye movements uniquely, and that individual differences between adult readers, resulting in differences in the quality of lexical representations these readers have, account for variability in patterns of reading above and beyond attributes of the text being read