In this study we explore how the physical movements teachers use can lead to improved interactions between students in a university language course. The study used video to capture and analyse an intervention focusing on the effects of teacher nodding. Results showed that positive measurable differences were found in students' physical postural responses in relation to the frequency with which their teacher nodded. The next stage of this preliminary research project will make use of the data gathered on micro-level interactions to develop technological support mechanisms to be used in the classroom to support teacher-student interactions. Keywords: physiological signals, teacher-student relationship, body posture, student interaction, micro-level interactions. [For the complete volume, "Intelligent CALL, Granular Systems and Learner Data: Short Papers from EUROCALL 2022 (30th, Reykjavik, Iceland, August 17-19, 2022)," see ED624779.]