Abstract: Under the COVID-19 situation, many universities attempt to make remote lectures interactive. To investigate the influence of interactivity on the quality of teaching, this paper compared students' concentration, arousal, and expressions between three lecture styles with different interactivity: remote with/without facial images, and face-to-face. We evaluated them by analyzing facial images and heart rate information. The results showed that the degree of concentration and arousal of students were significantly higher in the following order: face-to-face, remote with face image, and remote without face images. It was inconclusive whether students' expressions in remote lectures were the same as in face-to-face lectures. Based on these results, we discussed the future vision of remote lectures.