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6.4. Eye-tracking for Interaction
Figure 6.13: 2D gaze map for the case study. Left: Attentive character. Right: Distracted
character.
6.4.3.2 Case Study
Our results show that the subject strongly reacted to the change of behavior in the virtual
character. She glanced at the character once in a while at the beginning of the exposure.
She then looked down most of the time she was talking. This can be seen on the left of
Figure 6.13. It is clear from the eye-tracked points that there is an avoidance of salient facial
features. Figure 6.14 provides a clearer view of the tracked coordinates in time. The green
points indicate that the character is being looked at, whereas the red ones indicate avoidance.
This figure depicts a 20 second sample starting a couple of seconds after the exposure began,
as she was still looking at the therapist and not at the screen when the recordings started.
We can see that she looked at the character in the face at the very beginning but then looked
away most of the time.
When the character behavior change was triggered, and became bored and distracted,
we noticed a clear change in eye contact behavior. The subject started looking straight at
the character, as if trying to regain her attention. We can see, on the right of Figure 6.13,
that some of the points are right on the character’s face whilst this was not the case when
the character was attentive. Figure 6.15 shows the first 20 seconds of recordings after the
change in character behavior was triggered. We can see that at the beginning of character
behavior change, the subject is not looking at her. However, after a couple of seconds, which
corresponds to the time it takes for the behavior change to be visible, we can see that she is
looking at the character right in the face. There are still many points out of the character’s
face but many more are inside as compared to when the character was attentive. When
the character became attentive once again, however, there was no noticeable change in eye
contact behavior. Once the session was over, we asked the subject for some feedback on
how she perceived the public speaking exercise and the virtual character. She told us that
she had felt very anxious. She also told us that after a while, the character became bored
and started looking elsewhere, stopped listening to her. She clearly noticed the change in
character behavior. She explained that she expected the character to behave in this way from
the very beginning so it did not surprise her. She explained that this was the way she expected
any real person to react. She also said that she was trying to look at the virtual character at
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