Consider viewing a video lecture on how human kidneys work in which the instructor writes on a conventional whiteboard (as exemplifed in the left panel of Fig. 2) versus on a transparent whiteboard (as exemplifed in the right panel of Fig. 2). A conventional white- board is commonly used in classrooms, and in extreme situations the instructor only looks at the board while lecturing.
A transparent whiteboard involves a glass surface that the instructor stands behind and writes or draws on while facing the camera and lecturing. A computer algorithm then transposes the writing or drawing as a mirror image so it appears normal to the learner who views the video lecture. In this case, the instructor looks at the audience, shifts gaze to the board when she writes or draws, and shifts gaze back to the audience and so on.
Through continuously facing their audience and writing as they speak lightboard presenters can exploit two key principles that improve their teaching quality. These are:
Dynamic Drawing Principle – This states that people learn better from a video lecture when the onscreen instructor draws graphics on a board while lecturing, rather than referring to already drawn graphics.
Gaze Guidance Principle - This is where people learn better from a video lecture when the onscreen instructor shifts gaze between the audience and board while lecturing rather than looking only at the audience or board.
