I'm trying to read here! How does irrelevant speech affect how you read?

Reading involves a remarkable coordination of perceptual and linguistic processes. This coordination is reflected by a close coupling between reading eye movements and lexical properties of words, such as word frequency and predictability, as well as morpho-syntactic and semantic regularities. Yet, reading is also subject to interference, and a common source of interference is when others are speaking nearby. Then, how does irrelevant speech affect reading as reflected in eye movements? Fifty-nine participants (mean age: 19, SD age: 1.22, 25 females, 34 males, primary language: English) read passages from the PROVO corpus Luke and Christianson (Behav Res Methods 50(2):826-833. https://doi.org/10.3758/s13428-017-0908-4 , 2018) under intelligible irrelevant speech or the silence condition, with eye movements recorded. We investigated how irrelevant speech influences the coupling between eye movements and several indicators of lexical difficulty, including word frequency, cloze probability (exact-word predictability), large language model-generated surprisal, morpho-syntactic predictability (part-of-speech and inflection), and semantic similarity (general meaning). Associations between lexical variables and word looking times remained robust during first-pass reading and were unaffected by irrelevant speech, suggesting intact lexical processing during early stages of reading. However, disruption emerged in later eye-movement measures (i.e., total viewing time), where low-frequency and semantically unpredictable words prompted increased re-reading under irrelevant speech. These results indicate that intelligible irrelevant speech selectively interferes with post-lexical, higher-order processing. The increased re-reading of rare and semantically unpredictable words suggests that readers compensate for speech interference by revisiting these words to better integrate their meanings into a coherent understanding of the text.