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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Use of Tethered Virtual Reality Headsets in Exposure Therapy for Agoraphobia and Social Phobia</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Beatris Mariell Choo</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ana Margarita Talicol</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Elaine Jhon Panganiban</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ethel Chua Joy Ong</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>De La Salle University</institution>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2013</year>
      </pub-date>
      <fpage>80</fpage>
      <lpage>86</lpage>
      <abstract>
        <p>People with social phobia are characterized by a fear of being scrutinized, while people with agoraphobia have a fear of situations where escape may be difficult such as being in a crowded area. One way to support them is with the use of virtual reality technologies. Virtual reality (VR) allows people to easily step into and immerse themselves in a completely different environment, simulated by a computer. The ability that VR has to transport a person into a different place and interact with the virtual environment gives it potential as a tool for phobia treatment. In this paper, we explore the use of VR as a platform for people with agoraphobia and social phobia to practice social interactions towards the goal of overcoming their fear.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>Social anxiety disorder, also known as social phobia, is the
fear of scrutiny from others [World Health Organization,
2016]. Situations such as meeting new people, being
observed by others, and performing in front of a crowd can
trigger this fear. People suffering from social phobia fear being
thought negatively of by others, getting humiliated,
embarrassed, or being rejected [American Psychological
Association, 2013]. They tend to avoid social situations as a result of
this and thus affecting their way of living.</p>
      <p>Agoraphobia, on the other hand, is the fear characterized
by situations in which the person perceives to be difficult to
escape from if needed. It is highly recommended for
people with agoraphobia to have a companion with them,
specially when going out. Situations that may trigger their fear
include: using public transportation, being in open spaces,
being in enclosed places, standing in line, being in a crowd,
and being outside home alone [American Psychological
Association, 2013]. Like social phobia, agoraphobia can affect
the way a person lives. In severe cases of agoraphobia, the
individual may completely refuse to go outside of their homes
[American Psychological Association, 2013].</p>
      <p>
        Virtual reality (VR) is a computer simulated environment
whose goal is to immerse the user in an environment that is
different from what they already have around them. Using
head mounted displays that are either tethered to a PC or a
console, or mobile VR devices that are reliant on a
smartphone for both display and processing, VR has been used for
many things such as video games
        <xref ref-type="bibr" rid="ref14 ref3">(Farlands [Oculus, 2017],
Resident Evil 7 Biohazard [Capcom, 2017])</xref>
        , training
simulation
        <xref ref-type="bibr" rid="ref10 ref5">(High Voltage Switching [Computing, 2017], Virtual
Reality Crane &amp; Rigging Simulations [International, 2017])</xref>
        , and
healthcare
        <xref ref-type="bibr" rid="ref15">(Bravemind [Rizzo et al., 2010])</xref>
        . Under
healthcare, VR has been widely used to treat specific phobias, such
as acrophobia [Emmelkamp et al., 2001] [Rothbaum et al.,
1995] [Krijn et al., 2004], fear of flying [Ban˜os et al., 2002],
arachnophobia [Cavrag et al., 2014] and fear of cockroaches
[Wrzesien et al., 2013]. However, it is uncommon to use VR
for therapy of other types of phobia, such as social phobia.
      </p>
      <p>Exploring the application of VR in treatment of social
phobia and agoraphobia may uncover and answer questions about
the impact of interactions with virtual humans on therapy
patients, especially with the increased immersion provided by
the tethered VR headset. In this paper, we present our work
in developing a virtual reality environment as a platform for
people with agoraphobia and social phobia to practice social
interactions towards the goal of overcoming their fear.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Related Works</title>
      <p>A way to treat social phobia is by having the patient undergo
cognitive behavioral therapy (CBT). CBT is the combination
of techniques from cognitive therapy, in which the therapist
focuses on changing the patients perception over something;
and behavioral therapy, where the therapist instead works on
how the patient reacts to things [Lorenzo-Luaces et al., 2016].
CBT consists of four major variations: exposure, cognitive
restructuring, relaxation training, and social skills training
[Heimberg, 2002]. Each variation focuses on a different
aspect. For exposure, the focus is on having the patient face
their phobic stimuli. Cognitive restructuring focuses on
having the patient reevaluate the way they think about a situation
and then develop a different way of thinking towards it.
Relaxation training teaches the patient how to relax certain
muscle groups in their body. Finally, social skills training focuses
on addressing the behavioral deficiencies that a person with
social phobia may likely have, such as poor eye contact and
having poor conversational skills.</p>
      <p>While VR is lauded for its ability to allow humans to do
or experience something that is normally impossible, VR in
therapy exists primarily because VR allows users to indulge
in everyday experiences that they cannot perform normally
because of their condition. For example, a VR environment
created for confined or bedridden patients may feature scenes
where the patient is traveling from one place to another [VR
Kids, 2015]. VR environments in therapy vary in their
likeness to the real world; therapy environments for young
children often involve the use of animal-like companions [VR
Kids, 2015] while therapy environments meant for adults are
more realistic and attempt to mimic true experiences [Rizzo
et al., 2010] [Freeman, 2008].</p>
      <p>Bravemind [Rizzo et al., 2010] is a therapy tool made to
recreate situations a soldier would encounter in war. The
scenery was made to resemble areas such as Afghanistan or
Iraq, in areas where the solder may have encountered
traumatic experiences. While Bravemind employs the use of a
virtual reality headset, the soldier is asked to stay seated and
navigates the environment using a handheld controller. The
situations and encounters within the environment are fully
controlled by a therapist using a separate device.</p>
      <p>[Freeman, 2008] created a simulation to test for symptoms
of paranoia. The 4 minute simulation required the patient to
ride a virtual version Londons underground train from one
station to another. Afterwards, the patient was asked to
complete a series of assessment reports about their experience.
The results from the assessment reports were found to have
been able to predict symptoms of paranoia from physical
assault victims over the period of half a year. A separate study
using the same simulation found that the simulation did not
produce any unwanted effects on the individuals involved in
the testing. It was also concluded that the simulation was
effective in eliciting reactions that the individuals would have
had if they were undergoing a real life train ride
[FornellsAmbrojo et al., 2008]</p>
      <p>[Ban˜os et al., 2002] studied the effects of a VR therapy
treatment for the fear of flying. The environment allowed
the patient to undergo multiple scenarios that may trigger a
phobic response regardless of whether or not the patient was
actually inside a plane. The researchers involved in the study
asserted that regular exposure therapy for the fear of flying
is expensive and impractical, and justified the need for VR
treatments in exposure therapy.</p>
      <p>These studies have shown that VR has been effective in
assessing symptoms of and treating different mental illnesses,
and therefore allow for the assumption that VR can be used
to treat social phobia and agoraphobia.
3</p>
    </sec>
    <sec id="sec-3">
      <title>VR for Social Phobia and Agoraphobia</title>
      <p>According to [K Beesdo K, 2009], the first onset of anxiety
disorders can happen as early as the childhood or adolescent
age. Anxiety disorders may also develop following traumatic
events. An adolescent may experience trauma if they are the
victim of bullying in school, and may develop a phobic
response to school-related situations because of this trauma.
Students may exhibit symptoms of agoraphobia and social
phobia [American Psychological Association, 2013], such as
avoidance of the school-related situation unless accompanied
by a peer, as a result.</p>
      <p>To aid in treating these symptoms, the patient is exposed
to a virtual environment resembling a small school. In the
school environment, there are four main areas: a cafeteria, a
classroom, as seen in figure 1, a hallway and a teacher’s
office, which will be populated with virtual students, teachers
and staff. These areas were selected because of their age
neutrality, as opposed to an area such as a playground, which may
not be appropriate for older students, and because of the range
of social interactions that can happen in these environments.
Interactions in the virtual environment happen in the form of
conversations between the patient and the virtual humans.</p>
      <p>Before beginning the implementation, an ethics review was
performed in order to ensure the safety of the participants
who may be involved in testing the system. A licensed
psychotherapist provided their guidance to the researchers during
the design and implementation processes.</p>
      <p>The Oculus Rift has been selected as an interface for
increased immersion and for the use of hand gestures. This
will allow the environment to come across as more realistic
to the patient. Using voice input, room-scale VR navigation,
and hand gestures, the patient is expected to explore the
environment and perform various social interactions that they are
normally unable to perform.</p>
      <p>When the patient first uses the system, they will be asked
to provide their name, year of birth, gender, and preferred
gender for a virtual peer. This data, which are henceforth be
referred to collectively as the patient profile, will be saved and
made available for viewing by the psychotherapist later.</p>
      <p>To address social phobia, the patient will be presented
with a number of social situations that they may encounter
in school, such as introducing one’s self to a teacher, ordering
food from a canteen, or talking to a classmate. Each
situation is referred to in the system as an event, and each event
may have a prerequisite event that the patient may need to
complete beforehand. The patient will be “placed” in the
environment and will be asked to perform the selected event’s
task. There are six events currently defined in the
environment. Table 1 shows a list of these events and where they
take place.</p>
      <p>To address agoraphobia, the system will attempt to adjust
the number of virtual humans in the school according to the
patient’s anxiety level. Before and after the exposure proper,
the patient will be asked for their anxiety level on a scale of
0 to 10, or their SUDS score. The SUDS score taken before
the session is used to generate the environment and will be
inversely related to the crowdedness of the environment; that is,
the higher the SUDS score, the lower the number of people in
the environment. Through exposure and conversations with
the virtual peers in the environment, the patient is expected to
gradually be able to adapt to different social environments.</p>
      <p>There will be a virtual peer who can guide the patient
through the tasks to provide, at the very least, a familiar face
in the crowd of otherwise automatically and randomly
generated virtual humans. By clenching both their fists, the patient
may indicate to the virtual peer that they are feeling
overwhelmed. The peer will then guide the patient through a
relaxation exercise that can help the patient calm down. The
patient may then decide whether to continue with the
exposure proper or to end the exposure proper early.</p>
      <p>The design of the system presents an opportunity to collect
data about the behaviors of the patient during the exposure
proper. Apart from the patient profile, the SUDS score before
and after each session are collected. Those sessions whose
SUDS score is higher at the end than it was at the beginning
will be tagged and the psychotherapist can prioritize
reviewing these sessions. All conversations between the patient and
virtual humans will be also recorded. A list of keywords that
may indicate that the patient is at risk of harming themselves
or others has been compiled. Any conversations containing
these keywords will again be marked and recommended for
review to the psychotherapist. Lastly, the system will
collect data about how the session was ended, and the number
of times the virtual peer facilitated a relaxation exercise for
the patient. All collected data will be made available for the
psychotherapist to review and use.
4</p>
    </sec>
    <sec id="sec-4">
      <title>Issues Encountered</title>
      <p>Because only a microphone and the Oculus Rift peripherals
are used to take input, the system is unable to detect whether
the patient is becoming overwhelmed by the environment.
This information is needed in order to prompt the virtual peer
to step in and facilitate an exercise to help the patient relax.
Therefore, in lieu of other peripherals meant to detect anxiety
or fear, hand gestures will be the means by which the patient
can prompt the virtual peer.</p>
      <p>The presence of wires also poses a problem as the patient is
expected to walk around in the environment. This restricts the
patient’s movements within the environment, and may cause
issues in tracking the location of the patient in the
environment. While this issue is unavoidable as wireless tethered
headsets for VR have not yet been made available for
public consumption, it was minimized by re-mapping the areas
of the virtual environment to match the playing area of the
VR device in such a way that the patient need not step out
of bounds. Additionally, it is recommended that a
companion stay with the patient in order to ensure that they do not
encounter any accidents while using the VR headset, which
obscures their vision of their surroundings.</p>
      <p>Lastly, the weight of the tethered headset may cause
ergonomic problems to the patient if it is worn for an extended
period of time. In order to prevent fatigue, each individual
session was designed such that it would last no longer than
an hour. This restriction, however, presents a detraction from
a real life exposure session, which may normally last longer
than an hour. This detraction implies that there may be a
difference between the patient’s reactions and behaviors inside
the virtual environment than the data that would be collected
if the patient encountered the situation in real life. For
example, the patient’s behaviors if they are asked to wait in an
office for an extended period of time, or the patient’s
behaviors if they are asked to sit in a 90-minute class will not be
monitored beyond the first hour.
5</p>
    </sec>
    <sec id="sec-5">
      <title>Ongoing Work</title>
      <p>In this paper, we discussed the work we are doing to
investigate the potential use of virtual reality systems in exposure
therapy for people with agoraphobia and social phobia. Since
these anxiety disorders occur at an early age, we designed our
environment to simulate places, activities, events and
interactions in a school setting.</p>
      <p>At present, we are processing needed documents and
undergoing ethics reviews with relevant individuals in our
university and partner hospital to ensure that field testing with
patients will go smoothly. The virtual humans are also
undergoing remodeling while the integration with the Oculus Rift
is undergoing usability testing to create a more realistic and
immersive experience for the patient.</p>
      <p>Assuming that a professional can supervise the therapy
sessions and guide a cooperative patient, there is evidence to
show that VR-based solutions has a positive effect on
treatment [Rizzo et al., 2010]. The validity of these findings to
our system will be determined through actual testing with
participants who will be recommended by the
psychotherapist. These participants are students who have been diagnosed
with mild agoraphobia and social phobia, and should have
undergone cognitive behavioral therapy. It should be noted that
the system is meant as a support tool for exposure therapy,
and should be evaluated as such. The psychotherapist should
retain his/her control over the use of the tool by supervising,
designing and reviewing treatment sessions.</p>
      <p>Future research can use the data collected during the
exposure therapy sessions to discover patterns in behaviors of
patients suffering from and trying to recover from
agoraphobia and social phobia. The use of other wearables to detect
heartbeat or sweat levels to determine anxiety or fear, and use
this to adjust the environment dynamically as the patient
undergoes the exposure proper can also be explored.</p>
      <p>High voltage</p>
      <p>Rob Mclay. Development and early evaluation of the
virtual iraq/afghanistan exposure therapy system for
combatrelated ptsd. Annals of the New York Academy of Sciences,
1208:114125, 2010.</p>
    </sec>
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