A Predictive Comparison of the Selective Attention Hypothesis and Contextual Priming Theory in Processing English It-Extraposition: An Eye-Tracking Study

Abstract

When readers encounter an English it-extraposition structure (e.g., It is obvious that the minister resigned), two fundamentally different processing mechanisms could guide the resolution of the cataphoric dependency. The Selective Attention Hypothesis (SAH) holds that expletive it concentrates attentional resources on the matrix predicate, creating an integration cost that spills over onto the extraposed clause. Contextual Priming Theory (CPT), by contrast, claims that the matrix context pre-activates features of the upcoming clause, so that higher predictability reduces downstream effort. We adjudicated between these predictions in the first eye-tracking study of it-extraposition with advanced Libyan learners of English (N = 44). Participants read extraposed and non-extraposed sentences while their eye movements were recorded. Two linear mixed-effects models were constructed: an SAH model incorporating log frequency of the matrix adjective, and a CPT model incorporating offline cloze probability of the embedded-clause verb. The CPT model provided a significantly better fit than a baseline model (Δ − 2LL = 6.52, p = .011), with each one-unit increase in centred predictability reducing total reading time by 0.35 ms (f² = 0.04). The SAH predictor did not approach significance (Δ − 2LL = 1.23, p = .267). Follow-up analyses of early measures, regressions, and adjective-frequency interactions offered no support for an attentional bottleneck. We discuss the results in light of surprisal theory, Bayesian predictive coding, and constraint-based processing, and consider the possibility that SAH effects if present may require larger samples or different operationalisations to detect. The findings confirm that advanced L2 learners exploit the predictive affordances of the matrix context, and they carry direct implications for teaching grammar and reading in the Libyan EFL classroom.