Eye movements and the processing of function words in Brazilian Portuguese

Abstract

Research on eye movements during reading has focused on content words (CW), with comparatively less attention paid to function words (FW). This thesis investigated how CW and FW are processed during the reading of Brazilian Portuguese (BP), a language where both classes can carry syntactic information related to gender and number. We combined secondary analyses of eye movement data from the RASTROS corpus of natural reading in BP with three controlled eye-tracking experiments and one error-detection task. The corpus analyses in Study 1 replicated well-established word length, frequency, and predictability effects on fixation times and skipping rates. Differences between classes were limited to very early processing, where short FW were skipped more often than short CW. We interpret this as reflecting the redundancy of gender and number marking in BP, where syntactic information is readily and transparently repeated on the word following the FW. The differences in skipping rates were limited to short words because parafoveal word class identification is more likely for short words. The first experiment in Study 2 used the gaze-contingent boundary paradigm to replace parafoveal previews of target CW with syntactically illegal articles. Results showed a pattern similar to English, where syntactically illegal article previews were skipped more often than the correct target words, consistent with the ease of processing of highly frequent articles. The second experiment in Study 2, an error detection task, showed that participants detected the repetition of articles more than 90% of the time, highlighting how readers of BP are sensitive to ungrammatical repetitions of articles, in contrast with recent findings in English, where the error was noticed less than half the time. In Study 3, again using the gaze-contingent boundary paradigm, we examined parafoveal processing of syntactic gender information in article-noun phrases. Gender-incongruent parafoveal previews of the article (Experiment 1) produced no preview benefits or display change effects on the article-noun region, indicating that readers ignored the article. In contrast, manipulating gender information on the previews of the noun (Experiment 2) showed that gender information was acquired parafoveally from the noun, word n+2, when following a short article. This suggests that BP readers prioritise gender information from the upcoming noun, ignoring articles during parafoveal processing. In contrast, previous research in German showed readers seem to use gender information from both articles and nouns. Overall, the thesis demonstrates that proficient BP readers strategically allocate parafoveal attention away from short FW toward CW, suggesting that readers of different languages might employ different strategies to engage with syntactic parafoveal processing