There is ample evidence that reading speed increases when participants read the same text more than once. However, less is known about the impact of text repetition as a function of word class. Some authors suggested that text repetition would mostly benefit content words with little or no effect on function words. In the present study, we examined the effect of multiple readings on the processing of content and function words. Participants were asked to read a short text two times in direct succession. Eye movement analyses revealed the typical multiple readings effect: Repetition decreased the time readers spent fixating words and the probability of fixating critical words. Most importantly, we found that the effect of multiple readings was of the same magnitude for content and function words, and for low- and high-frequency words. Such findings suggest that lexical variables have additive effects on eye movement measures in reading.Keywords: text repetition, reading, word class, word frequency, eye movementsWhen readers read the same text more than once, they become faster at reading it (e.g., Raney & Rayner, 1995; Raney, Therriault, & Minkoff, 2010; Levy, Di Persio, & Hollingshead, 1992; Levy, Masson, & Zoubek, 1991). This phenomenon, known as the text repetition effect or the multiple readings effect, is particularly of interest since rereading is a common behavior, especially used to learn new information. Moreover, the study of text repetition provides an avenue for exploring the effect of text difficulty on the cognitive processes involved in reading. Although the multiple readings effect has been extensively investigated over the past decades, only a few studies have examined how text repetition influences the processing of individual words. In the present study, we tested this issue by contrasting eye movement measures for content and function words in two successive readings of the same text.Linguistic distinctions between function and content words are found in all languages and are thought to play a critical role in the acquisition of language (Shi, Werker, & Morgan, 1999). Function words provide grammatical relations between content words and consist of closed-class words that are primarily structural such as articles, prepositions, and auxiliaries. Most of the time, they include only one syllable and are very frequent in natural language (e.g., the, of, and, to). In contrast, content words convey the meaning of a sentence and correspond to open-class words such as nouns, verbs, adverbs, and adjectives. They are usually longer than function words and are less frequent in natural language. The linguistic distinctions between content and function words have been extensively studied. However, as pointed out by Schmauder, Morris, and Poynor (2000), the extent to which linguistic distinctions translate into psychological representations and processing distinctions has received much less attention.A number of studies have shown that content and function words might be processed differently during normal reading (e.g., Carpenter & Just, 1983; Drieghe, Pollatsek, Staub, & Rayner, 2008; Gauthier, O'Regan, & Le Gargasson, 2000; O'Regan, 1979; Schmauder et al., 2000). Using eye movements as a measure of cognitive processes involved in reading, those studies revealed that function words are less likely to be fixated than content words (but see Schmauder et al., 2000), a phenomenon called the "the-skipping effect" (e.g., Gauthier et al., 2000; O'Regan, 1979) or the word class effect (e.g., Levy, 1983; Roy-Charland, Saint-Aubin, Klein, & Lawrence, 2007). For instance, Carpenter and Just (1983) found that among three-letter words, function words received a lower proportion of fixation (.40) than content words (.57). This finding has been replicated recently by Drieghe et al., who showed that the French article "les" was skipped much more than three-letter verbs (see also Gauthier et al. …