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CHAPTER 7
Experimental Validation -
Agoraphobia
In this chapter, we present the experiment we have conducted over 30 healthy subjects in
order to validate our application concerning the interaction with crowds of characters in an
immersive environment. We first present the system setup in the CAVE environment before
explaining the experimental protocol. We then go over the results we have obtained and
discuss how our application could further be improved. Finally, we discuss the validity of
our application in the domain of VRET of agoraphobia.
7.1 Experimental Setup
The setup we used for the experiment relative to agoraphobia is depicted in Figures 5.1
and 7.1. It consists of several components. The same eye-tracking device is used as for
the social phobia setup. However, the magnetic sensor is replaced by a Phasespace optical
motion capture system [Phasespace, 2009]. Three LEDs are set on the eye-tracker headband
or on a baseball cap. More specifically, for participants wearing glasses or contact lenses,
we used the head-tracking only. In this case, the markers were set on the baseball cap. For
the participants who did not wear glasses or contact lenses, we used the combination of eyeand
head-tracking. In this case, the markers were set on the eye-tracker. These three markers
allow the definition of the position and orientation of the head in space. We used these two
different setups in order to verify the possible added value of using an eye-tracking device.
We actually wanted to check whether or not it was interesting to use the eye-tracking to the
detriment of stereoscopic vision. One of our aims with this study was thus to compare the
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