Effects of lexical and sublexical variables on visual word recognition are often treated as homogeneous across participants and stable over time. In this study, we examine the modulation of frequency, length, syllable and bigram frequency, orthographic neighborhood, and graphophonemic consistency effects by (a) individual differences, and (b) item repetition. A group of 129 participants performed lexical decision and naming, in counterbalanced order, using a set of 150 Greek words in which these variables were decorrelated. Frequency, length, and syllable frequency effects were reduced by a preceding task. Length effects were inversely related to years of education. Neighborhood effects depended on the metric used. There were no significant effects or interactions of bigram frequency or consistency. The results suggest that exposure to a word causes transient effects that may cumulatively develop into permanent individual differences. Models of word recognition must incorporate item-specific learning to account for these findings.