Technology changes often force teachers, trainers, instructional designers, and administrators to make instructional design and delivery decisions that ideally should be based upon pedagogy research. In many circumstances, however, a foundational pedagogy question is only recognized when a technology decision reveals it. Such is the case when deciding what mode (video or audio) to use for learner interaction in a synchronous online learning event. While some research has focused on the learning and the satisfaction of learners when they were interacting, almost no research has addressed the learning value of observing the interactions of other learners. The purpose of this research study was to investigate whether the mode in which direct learner interactions were made affected non-interacting learners' recall of content in a synchronous virtual learning environment. The participants in this study viewed one of three versions of a webinar on Multimedia Games for Learning: a) all learners interacted in video mode; b) all learners interacted in audio mode; or all learners interacted in both video and audio in a mixed mode. No statistically significant difference was found between the video, audio, and mixed treatment conditions in terms of the recall of content from the questions or comments made by directly interacting learners. However, a statically significant difference was found in non-interacting learners' recall of the contributions of direct interactors based on the mode of interaction within the mixed-mode group. Study participants recalled more of the contributions made in the audio mode of interaction than in the video mode when the modes were mixed. These findings suggest that designers of synchronous online learning may choose either video or audio mode without affecting those learners who are not directly interacting but should take care in mixing interaction modes within a single synchronous online learning event. The contributions of the study reach beyond the findings. The study supports vicarious interaction as a process worthy of research and e-Learning design consideration. It provides a model for experimental manipulation of "simulated" synchronous sessions, and it introduces recall of others' verbal contributions as an approach to measurement of the attention granted vicarious interactions by those not interacting directly with others.