Developmental dyslexia is a neurological condition characterized by unexpected low reading performance in people with normal intelligence and typical schooling. One prominent theory posits that dyslexic children fail to establish left-hemispheric dominance of visual representations and visual-phonological/meaning integration of printed words and thus exhibit an atypical lateralization of lexical processing. Behavioral, electrophysiological, histological, and morphological imaging studies examining this hemispheric asymmetry have generated conflicting evidence; however, it remains possible that dyslexics have impaired functional lateralization of language processes without a structural correlate. Here, using functional magnetic resonance imaging (fMRI) and a phonological task with working memory, we found distinct hemispheric asymmetry differences between dyslexic and normal children in brain regions subserving the storage and manipulation of phonological information in phonological working memory. Further, the degree of leftward asymmetry correlates positively with reading performance. Thus, the language impairments in dyslexic children appear related to a reduced dominance of the left hemisphere in phonological language functions, which offers clues into the biological dysfunction and possible remediation of developmental dyslexia

The instructor’s presence on the screen has become a popular feature in the video lectures of online learning and has drawn increasing research interest. Studies on the instructor presence effect of video lectures mainly focused on the features of the instructor, and few have taken learners’ differences, such as gender, into consideration. The current study examined whether male and female learners differed in their learning performance and eye movement features when learning video lectures with and without the instructor’s presence. All participants (N = 64) were asked to watch three different types of video lectures: audio-video without instructor presence (AV), picture-video with instructor presence (PV), and video-video with instructor presence (VV). They watched nine videos, three of each condition, and completed a reading comprehension test after each video. Their eye movement data were simultaneously collected when they watched these videos. Results showed that learners gained better outcomes after watching the videos with a talking instructor (VV) than those with the instructor’s picture (PV) or without the instructor (AV). This finding suggests that the dynamic presence of the instructor in video lectures could enhance learning through increased social presence and agency. Gender differences were found in their attention allocation, but not behavioral learning performance. When watching the videos with a talking instructor (VV), female learners dwelt longer on the instructor, while males transited more between the instructor and the text. Our results highlight the value of instructor presence in video lectures and call for more comprehensive explorations of gender differences in online learning outcomes and attention distribution.

Embodiment theories postulate that language processing inherently engages the sensorimotor system. This study explores the embodiment of action verbs in the second language (L2) and the effects of various L2 experiences (L2 age of acquisition, exposure, dominance, and proficiency) on L2 embodiment. Sixty-one Chinese–English bilinguals participated in two experiments judging semantic relatedness: Experiment 1 involved verb–picture pairs, while Experiment 2 focused on verb–verb pairs. Both experiments were conducted in the participants’ first language (Chinese) and second language (English), with the stimuli depicting actions performed by specific effectors (e.g., mouth, hand, and foot). Results showed that participants took longer to reject mismatched verb–picture pairs and semantic-unrelated verb–verb pairs when the actions shared the same effector (e.g., walk–run) than those involving different effectors (e.g., eat–touch). Moreover, L2 age of acquisition, exposure, and dominance correlated with the L2 embodiment effect, with L2 age of acquisition and exposure modulating this effect. This study enhances our understanding of L2 embodied semantics and illuminates the impact of multidimensional L2 experiences on embodiment.

This current study explores the influence of learners’ working memory capacity (WMC) on the facilitation effect of an instructor’s presence during video lectures. Sixty-four undergraduates were classified into high and low WMC groups based on their performance in an operation span task. They watched three types of video lectures on unfamiliar topics in a random order: video lectures with an instructor’s voiceover but without presence (VN), video lectures with the instructor’s face picture (VP), and video lectures with the same instructor talking (VV). We collected their eye movement data during the video lectures and their learning performance in the comprehension tests following each video. Two-way ANOVA and post-hoc analyses showed that the instructor’s presence significantly improved comprehension performance in only the low WMC group. They allocated more attention to the instructor’s face picture and talking head than the high WMC group. Our results highlight the value of the instructor’s presence as a social cue in video lectures, which is particularly beneficial for learners with a low WMC.

The present study used event-related potentials (ERP) to examine Chinese-English bilinguals’ reactive and proactive language control as they performed mixed-language picture naming with face cues. All participants named pictures in Chinese (first language, L1) and English (second language, L2) across three sessions: a 25% face-language matched session, a baseline session without face cues, and a 75% face-language matched session. Behavioral analyses for reactive language control showed that the asymmetrical switch cost was larger for L2 than L1 in the 25% session and for L1 than L2 in the 75% session. ERP results revealed more negative N2 and LPC during L1 switching in 25% session but enhanced N2 during L2 switching in 75% session. Similar N2 and LPC effect was found during L1 and L2 switching in the baseline context. For proactive language control, the reversed language dominance and enhanced LPC amplitudes during L2 naming were consistent across the three sessions. Our findings suggest that reactive but not proactive language control is modulated by the ever-changing face contexts, which highlights the highly flexible bilingual control systems subserving nonlinguistic cues.

The current study examined how native language (L1) orthographic features influence bilinguals' ability to rapidly form new representations for second-language (L2) written word forms. We assessed eye movements, neural activity, and behavioral performance in sequential bilinguals with L1-L2 orthographical pairs within (Spanish-English) and across (Mandarin Chinese-English) writing systems. Participants were trained on novel English words embedded in naturalistic sentence contexts, followed by a two-day post-training session. Analyses of eye-movement variables, fixation-related potentials, and learning outcomes revealed that Spanish-English bilinguals exhibited more automatic lexical encoding of novel words, reflected in shorter fixations and attenuated early neural responses, whereas Chinese-English bilinguals maintained prolonged attentional engagement across exposures. These divergent exposure-related dynamics predicted post-training performance, with Spanish bilinguals showing greater gains after consolidation. The findings suggest that the neuroplasticity underlying L2 word learning is shaped by pre-existing cortical circuits for native linguistic features, leading to different neural strategies for forming new lexical representations.