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Chapter 6. Experimental Validations - Social Phobia
Subject HSD - auditorium VSD - auditorium HSD - bar VSD - bar
CA 81.42 / 76.03 97.49 / 39.02 62.11 / 50.48 58.00 / 38.07
CB 90.38 / 98.89 54.35 / 80.00 45.53 / 54.82 71.81 / 48.59
CC 42.94 / 43.06 39.75 / 43.78 11.35 / 23.49 20.03 / 33.21
CD 69.93 / - 85.31 / - 51.53 / - 48.21 / -
CE 47.95 / - 38.64 / - 33.86 / - 83.92 / -
Table 6.3: Standard deviation for control subjects. Pre-treatment / Post-treatment.
Subject HSD - auditorium VSD - auditorium HSD - bar VSD - bar
PA 27.02 / 71.00 24.03 / 40.38 35.38 / 64.51 41.43 / 43.02
PB 25.21 / 39.86 41.65 / 40.67 21.11 / 17.46 44.57 / 35.24
PC 77.77 / 74.60 83.63 / 48.34 75.89 / 64.95 102.07 / 65.05
PD 82.89 / - 58.07 / - 72.38 / - 70.68 / -
PE 55.10 / - 19.43 / - 35.17 / - 39.05 / -
Table 6.4: Standard deviation for phobic subjects. Pre-treatment / Post-treatment.
clearly demonstrated hypervigilance. The subjects from the control group mostly looked at
the central character in the first row, but also at the whole audience. On the other hand, only
one of the five phobic subjects showed a visual behavior corresponding to the control group
subjects’. Four of them focused on one or two characters only. This can be seen in the examples
shown in Figure 6.8 where the phobic subject clearly concentrates on a single character
whilst the control group one looks at the whole audience.
We have also measured the standard deviation (SD) for each subject. As can be seen in
Table 6.3, the values obtained from the control subjects are all above 40 for the horizontal
component (HSD) and near 40 and more for the vertical component (VSD). These values
are not surprising since looking at the whole audience, i.e., the whole width and height of
the screen, translates to high SD values. Table 6.4, containing the data for the phobic group,
shows that PC and PD have values similar to those of the control group. PB and PE have one
of the two components which is significantly smaller in the pre-therapeutic phase and PA
clearly has values very much below those of the control group in the pre-therapeutic phase.
However, both PA and PB have values corresponding to those of the control subjects in the
post-therapeutic phase. It is important to note that for this scene, the horizontal deviation is
much more important than the vertical one due to the image properties; the virtual characters
being mostly on the bottom part of the projected image but spread out over its width.
In the second scene, the bar scene, since there is only one main character to which the
subject is speaking, non-phobic subjects look at that person in the face, and more specifically,
at that character’s salient facial features (eyes, nose and mouth). Numerically, this translates
in small SD values. On the other hand, a phobic subject prone to visual avoidance behaviors
will look at anything but salient facial features. All subjects from the control group mostly
looked at that character in the face while talking to him. Four of the subjects from the phobic
group equally behaved this way. Subject PC, however, clearly demonstrated an avoidance of
the character’s salient facial features.
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