AI matches human teachers: Brief pre-lecture chat boosts students' brain synchrony and learning outcomes

Millions of students worldwide have long relied on self-paced learning through pre-recorded video lectures, a model that forms the backbone of massive open online courses (MOOCs) and large-scale online education. Since the COVID-19 pandemic, dependence on video-based online learning has increased significantly, with learner participation rising sharply. However, this expansion has also been accompanied by a widespread decline in student engagement, undermining overall learning outcomes.