Visual Contextual Cues Selectively Modulate Online Processing During L2 Incidental Vocabulary Learning: The Role of Heritage Background

Visual features surrounding text can shape learners’ attentional allocation and online processing, yet their role in second language (L2) incidental vocabulary learning remains underexplored. Drawing on cognitive load and multimedia learning perspectives, external visual cues may influence learners’ allocation of limited cognitive resources during reading, while extraneous visual information imposes additional demands, under cognitively demanding L2 input. The present study examined whether frame color influenced online and offline measures of incidental vocabulary learning, and whether these effects differed by heritage background. The participants (26 heritage and 26 non-heritage L2 learners) read three texts containing 18 novel words presented with no-color, yellow, or blue frames. The data were analyzed using mixed-effects models, with proficiency and area of interest (AOI) length included as covariates. The results showed no significant effects of frame color or heritage background on offline outcomes. However, frame color selectively influenced online eye-movement behavior, primarily in fixation counts and rereading measures. Heritage background was also significant, with non-heritage learners showing longer go-past times. The interaction between frame color and heritage background in second-pass fixation counts was not statistically significant, while follow-up comparisons revealed a significant color difference among non-heritage learners only. These findings suggest that peripheral visual cues primarily influence later attentional rereading rather than early lexical processing, while online changes do not necessarily translate into vocabulary learning gains.