Participants were exposed to a series of short video clips for 20 minutes in all three experimental conditions, i.e., 2D mode, 3D active mode, and 3D passive mode. However, the auditory stimulus was also present during the experiment but was kept at a very minimum volume. The inclusion of minimal auditory information was necessary in order to replicate the cinematic experience (but in a controlled setting) and it was also to prevent the viewers from feeling bored and drowsy over time.
In this experiment, a set of short video clips was used as the stimuli. The video clips were produced by Sony (“Sony Blu-Ray 3D Experience 2010, volume 2”), which was commercially available and contained good quality 3D content. The video clips were selected from the recommended imaginary animated and natural movies. Although different video clips may result in different brain and heart responses, the content of the video clips was not the main concern, since the same video clips were employed for 2D, 3DA (3D active shutter glasses), and 3DP (3D passive polarized glasses) viewing. Hence, the corresponding responses in each viewing mode can be observed by computing the difference between viewing modes. The description of all the video clips is summarized in Table 6.2.