Virtual
reality (VR) offers today a new paradigm for human-computer interaction,
in which users are no longer simply external observers of images
on a computer screen, but active participants within a computer-generated
three-dimensional world. As such, this environment provides a
protected and convenient setting for psychological treatments.
Most of the psychological therapies carried out with the help
of virtual reality relies on the principle of exposure, consisting
in confronting and accustoming the patient to the stress situation.
Case studies demonstrating the effectiveness of the exposure provided
by virtual reality have been reported on fear of flying, acrophobia,
claustrophobia and agoraphobia. In comparison with the use of
this technique in the real world (in vivo exposure), virtual reality
shows less constraints. One of principal assets of a treatment
in Virtual reality is the possibility for the therapist to control
the intensity of the stimuli administered (e.g. variations of
the stress situations, addition of new modes of stimulation: tactile,
visual, etc.) in order to make their progression continuous and
soft. In addition, the patient - like the therapist - has the
possibility to stop the simulation immediately in case of problems
(faintness, poor comprehension of the instructions, …) and
discuss them, a solution that is not always possible during an
in vivo exposure. Virtual reality proves advantageous also in
a specific type of exposure, namely, 'systematic desensitisation',
where the patient is asked to imagine the anxious stimuli. The
problem with this technique is that some patients are not able
or too phobic to imagine the situation prescribed by the therapist
and that there is no control on what the patient actually imagines.
Presenting the situation via a VR simulation may then help avoiding
these problems. Opportunities and limits of a virtual reality
therapy will be reviewed in this paper.
