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CHAPTER 6
Experimental Validations - Social
Phobia
In this chapter, we first go over the equipment we used in our various experiments in the
context of social phobia. We then describe three different experiments we have conducted
in this domain. The first was done in order to validate the scenarios we have discussed in
Chapter 3.2. The second experiment was done in order to evaluate the potential of eyetracking
for the diagnosis and assessment of social phobia. Finally, our third experiment
evaluates the potential of the application we have described in Chapter 3.3 which allows
interaction between a user and virtual characters based on gaze behaviors.
6.1 Experimental Setup
The equipment setup we used to conduct the experiments relative to social phobia is depicted
in Figure 6.1. This setup contains various components. The first one is a head-mounted eyetracking
device, depicted on the left of Figure 6.2. This device is an ISCAN RK-726PCI
pupil/corneal reflection tracking system [Iscan, 2009]. It is a head mounted system which
operates at 60 Hz. It is composed of two cameras, one directed toward the eye and the other,
in the opposite direction. It also has a dichroic mirror and an infrared eye illuminator. It
tracks the subject’s pupil and a reflection from the corneal surface. The distance between
the two then allows the determination of the eye position, and the POR. In order for this to
function properly, the subject first has to go through a calibration process. This consists of
successively looking at five points projected on screen; on the top left, on the top right, in
the middle, on the bottom left and on the bottom right. During this process, the user has
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