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Virtual Reality Induces Dissociation and Lowers Sense
of Presence in Objective Reality
Frederick Aardema, Ph.D.,
1,2,3
Kieron O’Connor, Ph.D.,
1,3
Sophie Coˆte´ , Ph.D.,
4
and Annie Taillon, M.Sc.
1
Abstract
This study utilizes an innovative experimental paradigm to investigate the effects of virtual reality (VR) on
dissociative experience and the sense of presence. A nonclinical sample of 30 people were administered mea-
sures of dissociation, sense of presence, and immersion before and after an immersion in a virtual environment.
Results indicate an increase in dissociative experience (depersonalization and derealization), including a less-
ened sense of presence in objective reality as the result of exposure to VR. Higher preexisting levels of disso-
ciation and a tendency to become more easily absorbed or immersed were associated with higher increases in
dissociative symptoms resulting from VR immersion. Results are discussed in terms of imaginative processes
underlying the dissociative experience and potential implications to the treatment of anxiety disorders with VR.
Introduction
Dissociative disorders, and particularly depersonal-
ization disorder (DPD), have generated increased in-
terest from researchers in recent years. DPD is a sense of
detachment and unreality toward oneself or the external
world. The symptoms of depersonalization and derealization
(DP=DR) lie on a continuum ranging from normal, everyday
cognitive processes (such as daydreaming) to clinical mani-
festations such as full-fledged chronic dissociative disorder.
1
Epidemiological studies indicate that the life-time prevalence
of DP=DR is 34% to 70% in nonclinical populations,
2
sug-
gesting that some level of dissociative experience is a normal
phenomenon.
Cognitive-behavior formulations of dissociative experience
and its pathological manifestations are still in the early stages,
although imagination inflation and fantasy proneness have
been identified as relevant factors in dissociative experi-
ences.
3–5
In particular, it has been suggested that a tendency
to become easily absorbed into the imagination may give rise
to a feeling of detachment and sense of unreality toward the
external world. More recently, cognitive-behavior formula-
tions have also identified a strong focus on the self, often
characterized by frequent questioning and catastrophic mis-
interpretation of transient symptoms, which may exacerbate
feelings of DP=DR.
6
The construct of dissociation is ill defined, frequently re-
ferring to a wide variety of nonclinical and clinical phenom-
ena, which often leads to confusion among researchers and
theoreticians.
7
Holmes et al.
7
suggest two qualitative distinct
forms of dissociation, one characterized by compartmentali-
zation phenomena with dissociative amnesia as a central
feature, and the other primarily characterized by feelings of
detachment, which incorporates symptoms of DP=DR. A
sense of detachment is a distinct feature of dissociative ex-
perience in general, which may take on either a pathological
format as in the case of DPS or a nonpathological format
when associated with fatigue or mild intoxication.
Interestingly, according to these definitions, research into
virtual environments has also focused on concepts closely
related to a sense of detachment from reality. In particular,
it highlights the importance of constructs like the level of
immersion and presence. The feeling of immersion, whether
physical or psychological in nature, allows the user to either
feel or believe that he or she has left the real world and is now
interacting with a virtual environment. Unlike research on
dissociative disorders, however, these constructs generally
refer to level of immersion and presence with respect to a
particular virtual environment (as opposed to the level of
immersion and presence within objective reality). Yet the
concepts are quite similar and seem closely interrelated. In
fact, a higher degree of immersion or presence in a virtual
environment would naturally imply a greater level of de-
tachment from external reality. In particular, it has been
suggested that those prone to dissociative symptoms have
more difficulty tolerating discontinuity in perceptual
1
Fernand-Seguin Research Center, Montreal, Canada.
2
Concordia University, Montreal, Canada.
3
University of Montreal, Montreal, Canada.
4
Centre hospitalier de l’Universite
´de Montre
´al, Montreal, Canada.
CYBERPSYCHOLOGY,BEHAVIOR, AND SOCIAL NETWORKING
Volume 13, Number 0, 2010
ªMary Ann Liebert, Inc.
DOI: 10.1089=cpb.2009.0164
1
CPB-2009-0164-Aardema_2P.3D 01/27/10 6:20pm Page 1
environments, often reflecting a rigid stance toward percep-
tion.
3,4
As such, perceptual discontinuity as induced by
temporarily being immersed into a virtual environment while
absorption into objective reality is discontinued would be
expected to increase dissociative symptoms among those
prone to dissociative symptoms.
The present study introduces an innovative experimental
paradigm that identifies imaginative processes associated with
dissociative experience using virtual reality (VR) to decrease
the sense of presence in objective reality and increase feelings
of detachment toward objective reality. We predict that (a)
exposure to a virtual environment induces dissociative expe-
rience; (b) exposure to a virtual environment leads to a lower
sense of presence in objective reality; (c) the level of presence in
objective reality is associated with a higher degree of disso-
ciative symptoms after exposure to a virtual environment; and
(d) the degree of dissociative symptoms induced by a virtual
environment is associated with preexisting imaginative ten-
dencies and level of dissociative symptomatology.
Method
Participants
Participants were recruited through an advertisement in
the employee newspaper of the staff of Ho
ˆpital Louis-
Hippolyte Lafontaine (Montreal, Quebec). Participants were
initially screened by a telephone interview utilizing a mental
health screening questionnaire, the Questionnaire sur la
sante
´.
8
People with a potential anxiety disorder, depressive
disorder, substance abuse disorder, or psychotic disorder
were excluded. The final sample consisted of 30 participants
(14 females, 16 males). The average age was 33.1 (SID ¼8.2;
range 22–49). Educational levels were as follows: 3.3% had
a primary education, 0.0% had a secondary education, 36.7%
had a postsecondary preparatory college education, and
60.0% had a university education. Marital status was as fol-
lows: 56.7% married or cohabiting, 40.0% single, and 3.3%
divorced or separated.
Questionnaires
Cambridge Depersonalization Scale–Trait Version (CDS-
T). The CDS-T
9
measures the frequency and duration of
DP=DR symptoms over the previous 6 months (trait version).
It was tested on a sample of 77 patients suffering from a DSM-
IV depersonalization disorder (35), an anxiety disorder (22),
or a temporal lobe epilepsy (20).The scale consists of 29 items
capturing the frequency (0, never,to4,all the time) and general
duration of symptoms (1, few seconds,to6,more than a week).
The scale showed good discriminant validity (r¼0.25–0.29),
convergent validity (r¼0.80), and high internal consistency
(a¼0.89).
9
In addition, the total score of the scale differenti-
ates patients with DSM-IV depersonalization disorder from
the other groups.
Cambridge Depersonalization Scale–State Version
(CDS-S). The CDS-S
9
has 22 items representing clinical
manifestations of depersonalization symptoms using a visual
analogue scale that requires the participant to mark answers
along a numerically anchored 100-millimeter line. The scale
ranges from 0% (‘‘I’m not having it at all’’) to 100% (‘‘It’s as
bad as it gets’’). Most of the items correspond to the trait
version but were adapted by the original authors to allow for
the state measurement of symptoms of depersonalization.
The total score is calculated by adding the item scores. The
scale showed excellent internal consistency and reliability in
the present study (a¼0.92).
Adapted Igroup Presence Questionnaire (AIPQ). The
AIPQ is an adapted version of the Igroup Presence Ques-
tionnaire (IPQ).
10
The IPQ and its modified version, the AIPQ,
contain original items from previously developed question-
naires.
11–14
The original IPQ was constructed using a large
pool of items and two survey waves with approximately 500
participants. Items are answered on a 6-point scale (3to3).
The AIPQ used only those items from the original IPQ whose
contents allowed for the measurement of sense of presence in
objective external reality as well as in a virtual environment. In
some cases, items were rephrased so that they could apply to
both objective reality and a virtual environment. In addition,
because one purpose of the present study was to measure
sense of presence in both virtual and objective reality, two
different versions of the AIPQ were used, and while there were
no differences in the item set, each version had a slightly dif-
ferent instruction. For the measurement of presence in objec-
tive reality, the instruction was as follows:
Now you’ll see some statements about experiences. Please
indicate whether or not each statement applies to your expe-
rience in the last 5 minutes. You can use the whole range of
answers. There are no right or wrong answers, only your
opinion counts. Note that the expression ‘‘world surround-
ings’’ refers to the physical, ‘‘real’’ world.
For the measurement of presence in a VR environment, the
phrase ‘‘physical ‘real’ world’’ was replaced with ‘‘the virtual
world only.’’
The AIPQ consisted of nine items answered on a scale
ranging from 3 to 3. Item-total correlations of the AIPQ for
the first measurement (in objective reality) ranged from 0.23
to 0.66 (Cronbach’s a¼0.73). Item-total correlations of the
AIPQ for the second measurement (in the virtual environ-
ment) ranged from 0.12 to 0.86 (Cronbach’s a¼0.86). Higher
(recoded) scores indicate a greater sense of presence in ob-
jective reality, or alternatively, if the instruction applied to
VR, higher scores indicated a greater sense of presence in VR.
Immersive Tendency Questionnaire (ITQ). The ITQ
15
measures the tendency or capability to be involved or im-
mersed in activities, including the ability to concentrate and
block out distractions. Typical items include ‘‘Do you ever
become so involved in a daydream that you are not aware of
things happening around you?’’ ‘‘How good are you at
blocking out external distractions when you are involved in
something?’’ The scale consists of 18 items answered on a 7-
point scale. Reliability of the questionnaire is satisfactory
(a¼0.75).
Dissociative Experiences Scale (DES). The DES
16,17
is a
self-report questionnaire designed to identify patients with
dissociative psychopathology and to provide a means of
quantifying dissociative experiences. Content for the scale’s
28 items was garnered from interviews with dissociative
patients and from consultations with clinical experts. The
scale taps a broad range of dissociative experiences, including
2 AARDEMA ET AL.
CPB-2009-0164-Aardema_2P.3D 01/27/10 6:20pm Page 2
disturbances in memory, identity, and cognition and feelings
of derealization, depersonalization, absorption, and imagi-
native involvement. The final score is calculated by dividing
the total score by 28. Reliability findings from various studies
range from 0.85 to 0.93. Factor analysis performed on data
from nonclinical samples yields a different factor structure
than on clinical samples.
18
Specifically, in nonclinical sam-
ples, most of the variance is explained by an absorption factor
with factor loadings from 10 DES items (12, 14, 15, 16, 17, 18,
20, 22, 23, and 24). Hence, for the current study, only the
subscale Absorption was used (DES-AB), which reflects a
higher degree of dissociative experiences characterized by
absorption and imaginative involvement (e.g., ‘‘Some people
have the experience of not being sure whether things that
they remember happening really did happen or whether they
just dreamed them’’). The total score on the DES-AB is de-
termined by calculating the average score for all items.
Inferential Confusion Questionnaire–Expanded Version
(ICQ-EV). The ICQ-EV
19
is a 30-item questionnaire based
on the original version of the Inferential Confusion Ques-
tionnaire.
20
The total score represents a tendency to confuse
reality with imagination, including a distrust of the senses
and a tendency to easily get absorbed in the imagination. The
ICQ-EV has strong psychometric qualities with a high reli-
ability (a¼0.96) and validity.
Beck Depression Inventory II (BDI). The BDI
21
is a 21-
item measure that assesses the severity of depressive symp-
toms experienced by respondents during the previous 2
weeks. The BDI is highly reliable and valid (a¼0.92).
Beck Anxiety Questionnaire (BAI). The BAI
22
is a 21-item
anxiety symptom checklist on a 0 to 3 scale. The instrument
shows high internal consistency (a¼0.91), good test–retest
reliability (r¼0.75), moderate convergent validity (r¼0.51),
and good discriminant validity (r¼0.25).
Procedure
At the beginning of the experiment, participants were
asked to fill in the consent form and complete the entire
battery of questionnaires. This included a measurement of
sense of presence in objective reality during the last 5 minutes
(AIPQ). Upon completion of the first battery of question-
naires, participants were instructed to explore the virtual
environment at will for the next 15 minutes. To enhance im-
mersion, participants were asked to note the number of
people and cars encountered in the VR environment.
Following 15 minutes of exploring the VR environment,
participants were removed from the environment and asked
to fill in the AIPQ with the instructions pertaining to the VR
environment (e.g., how he or she felt during the last 5 minutes
while inside the VR environment). Once the AIPQ was
completed, participants were asked to explore the VR envi-
ronment once more for another 10 minutes. Therefore, in
total, each participant spent 25 minutes in the VR environ-
ment, which was considered sufficient time for immersion
into a VR environment without triggering confounding fac-
tors such as cybersickness.
Once the last 10 minutes of exploration of the VR envi-
ronment was completed, participants were asked to stay in the
room for 5 minutes before completing the post-questionnaires
(CDS-S and AIPQ). During post-measurement, the AIPQ was
administered to measure presence in objective reality for the
last 5 minutes. The participant was then debriefed and given
an explanation of the study’s purpose.
Material
The VR environments were displayed using a computer
with Windows 2000 (Pentium III, 4.2 GHz, 1 GB of RAM, with
a nVidia GeForce4 Ti 4200 128 MB), anIntertrax2 motion
tracker from Intersense (USB model, 3DOF, update rate
256 Hz), an I-Glass SVGA head-mounted display by IO-
Display (800600, 268FoV diagonal), and a Gyration wireless
mouse. The VR environments were created using a 3D game
editor (see www.uqo.ca=cyberpsy for demos).
Results
Means and standard deviations
Means and standard deviations of the administered ques-
tionnaires before exposure to a VR environment are shown in
Table 1.
Baseline intercorrelations between the questionnaires
To provide further insight into the relationships among the
various constructs and to better interpret the results of the
experimental manipulation, we calculated the intercorrela-
tions among the measures in the total sample (n¼30).
Most of the questionnaires measuring imaginative pro-
cesses were strongly related to each other (Table 2). While the
magnitude of correlations must be interpreted carefully due
to the small sample size, this result is not surprising. To some
extent, all the questionnaires relate to absorption or imagi-
native involvement. In particular, immersion tendencies, as
measured by the ITQ, were strongly related to dissociative
experiences characterized by absorption as well as feelings of
DP=DR, as measured by the CDQ. Likewise, a tendency to
confuse the imagination with reality, as measured by the
ICQ-EV, was significantly related to most other imaginative
measures. Sense of presence in objective reality related most
strongly to depression, as measured by the BDI, and related
moderately to feelings of DP=DR as measured by the CDQ.
However, sense of presence did not relate to any of the
measures such as the ICQ-EV, the ITQ, and the DES-AB. Most
of the other measures related to general distress, as measured
by the BAI and BDI. However, a tendency to become more
Table 1. Means and Standard Deviations
Instrument Mean SD
Adapted Presence Igroup Questionnaire 20.00 6.10
Cambridge Depersonalization
Questionnaire–State
48.80 110.90
Cambridge Depersonalization
Questionnaire–Trait
17.60 19.10
Dissociative Experiences Scale–Absorption 13.20 13.11
Immersive Tendencies Questionnaire 63.30 15.70
Inferential Confusion Questionnaire 61.70 28.60
Beck Anxiety Inventory 4.10 4.29
Beck Depression Inventory 4.63 7.16
VIRTUAL REALITY AND DISSOCIATIVE EXPERIENCE 3
CPB-2009-0164-Aardema_2P.3D 01/27/10 6:20pm Page 3
easily immersed, as measured by the ITQ, was not signifi-
cantly related to the BAI and BDI.
Effects of VR on DP=DR
The effects of VR on symptoms of DP=DR (as measured by
the CDS-S) are shown in Figure 1(A). Paired samples ttest
revealed a significant difference between pre- and post-
measures of symptoms of DP=DR: t(1, 29) ¼3.03; p¼0.003,
one-tailed. Overall, there was a significant increase in
symptoms of DP=DR as the result of exposure to a virtual
environment (4.9–14.5%).
To investigate the effects of VR in subgroups, participants
were divided into high and low DP=DR subgroups on the basis
of preexisting trait levels of DP=DR using the median score
(11.69) of the CDS-T. The effects of VR for these subgroups
on symptoms of DP=DR, as measured by the CDS-S, are shown
in Figure 1(B). Repeated measures of variance revealed a
FIG. 1. (A) Effects of virtual reality on depersonalization and derealization (CDS-S) in the total sample (n¼30). (B) Effects of
virtual reality on depersonalization and derealization in high and low subgroups (CDS-T).
Table 2. Interrelationships Between Dissociative Experience and Imaginative Processes Measures
CDQ-S CDQ-T DES-AB ITQ ICQ-EV BAI BDI
AIPQ 0.48** 0.41* 0.28 0.10 0.21 0.42** 0.62***
CDQ-S 1.00 0.73*** 0.77*** 0.43** 0.75*** 0.70*** 0.71***
CDQ-T — 1.00 0.77*** 0.47** 0.67*** 0.51** 0.62***
DES-AB — — 1.00 0.69*** 0.65*** 0.49** 0.62***
ITQ — — — 1.00 0.69*** 0.31 0.35
ICQ-EV — — — — 1.00 0.64*** 0.54**
BAI — — — — — 1.00 0.32
BDI — — — — — — 1.00
Note.*p<0.05; **p<0.01; ***p<0.001; BDI, Beck Depression Inventory; BAI, Beck Anxiety Questionnaire, ICQ-EV, Inferential confusion
Questionnaire-Expanded Version; CDS-T, Cambridge Depersonalisation Scale-Trait Version; DES-AB, Dissociation Experiences Scale-
Absorption Subscale; AIPQ, Adapted Igroup Presence Questionnaire; CDS-S, Depersonalisation Scale-Trait Version.
4 AARDEMA ET AL.
CPB-2009-0164-Aardema_2P.3D 01/27/10 6:20pm Page 4
significant interaction effect: F(1, 28) ¼3.85, p¼0.03, one-tailed;
Z
2
¼0.12; observed power ¼0.47). Those with higher initial
levels of symptoms of DP=DR showed a greater increase in
state symptoms (M
pre
¼89.8, SD ¼147.2; M
post
¼245.8, SD ¼
318.9) than those with lower initial levels of symptoms of
DP=DR (M
pre
¼7.9, SD ¼15.1; M
post
¼44.7, SD ¼75.3).
Effects of VR on sense of presence
For the total sample, level of presence before, during, and
after exposure to VR is represented in Figure 2. Level of
presence in VR was significantly lower than in objective re-
ality: t(1, 29) ¼6.26 (1, 29); p<0.001, one-tailed. Participants
felt considerably less present in the virtual environment than
they did in actual objective reality. Immediately after expo-
sure to the VR environment, however, participants did not
reach the same level of presence in objective reality as they
had before: t(1, 29) ¼3.64; p<0.001, one-tailed).
In addition, repeated measures of variance showed that
both subgroups (low and high on symptoms of DP=DR) felt
considerably less present in objective reality after exposure to
VR: F(1, 28) ¼38.09; p<0.001, one-tailed; Z
2
¼0.58; observed
power ¼1.00. However, there was no significant interaction
effect between the groups when comparing preexisting levels
of presence in objective reality with levels of presence in VR:
F(1, 28) ¼0.04; p<0.42, one-tailed; Z
2
¼0.00; observed pow-
er ¼0.05. In addition, when comparing the levels of presence
in objective reality before and after VR, both the group high
on symptoms of DP=DR (M
pre
¼17.9, SD ¼6.8; M
post
¼8.5,
SD ¼12.2) and the group low on symptoms of DP=DR
(M
pre
¼22.2, SD ¼4.4; M
post
¼16.7, SD ¼12.1) showed a de-
crease in sense of presence in objective reality: F(1, 28) ¼13.15;
p<0.001, one-tailed; Z
2
¼0.32; observed power ¼0.94. How-
ever, neither group showed a significantly greater reduction
in level of presence than the other: F(1, 28) ¼0.86; p<0.18,
one-tailed; Z
2
¼0.03; observed power ¼0.15.
Correlates of change in presence
and dissociative experience
What are the main variables that relate to change in symp-
toms of DP=DR symptoms and change in presence in objective
reality as the result of an immersion in VR? To answer this
question, we calculated the relationship between change in
symptoms of DP=DR and level of presence in objective reality
with all of the other measures. Results showed that change in
symptoms of DP=DR due to VR exposure, as measured by the
CDQ-S, was most strongly related to preexisting levels of
DP=DR as measured by the trait version of the CSQ (r¼0.71;
p<0.001, two-tailed). Change in symptoms of DP=DR was
also significantly related to the DES-AB (r¼0.52; p<0.01, two-
tailed). Immersive tendencies, as measured by the ITQ, were
also significantly related to change in symptoms of DP=DR
(r¼0.42; p<0.05, two-tailed). In addition, change in symp-
toms of DP=DR was significantly related to a tendency to ab-
sorb oneself in imaginary possibilities, as measured by the ICQ
(r¼0.45; p<0.05, two-tailed). No significant relationship was
observed with preexisting moodstates as measured by the BAI
(r¼0.33; p¼0.08) and BDI (r¼0.29; p<0.13). Finally, change
in symptoms of DP=DRwas quite strongly related to change in
presence in objective reality before and after immersion in VR
(r¼0.58; p<0.001, two-tailed). The greater the increase in
symptoms of DP=DR, the greater the decrease in one’s sense of
presence in objective reality. Change in presence was not re-
lated to any of the other variables.
Discussion
The current study used an innovative experimental ap-
proach to investigate the effects of VR on dissociation experi-
ence and sense of presence in objective reality. Dissociative
symptoms were measured before and after exposure to a VR
environment, and results showed an increase in symptoms of
DP=DR following VR exposure. In particular, those with initial
higher levels of dissociative symptoms showed a greater in-
crease in dissociative symptoms following exposure to VR than
did those with lower levels of dissociative symptoms. Sense of
presence in objective reality also decreased as the result of ex-
posure to VR. However, this time, preexisting levels of DP=DR
did not mitigate the effects of VR on level of presence.
The current results shed light on various imaginative fac-
tors involved in the production of dissociative symptoms.
They showed that the feeling of presence in a virtual envi-
ronment, which implies detachment from objective reality,
may temporarily compromise one’s connection with outer,
objective reality. A tendency toward immersion or ab-
sorption, as measured by several different scales, related
significantly to level of change in dissociative symptoms as
the result of VR. The current results provide support for the
FIG. 2. Effect of virtual reality on presence (AIPQ) in the total sample (n¼30).
VIRTUAL REALITY AND DISSOCIATIVE EXPERIENCE 5
CPB-2009-0164-Aardema_2P.3D 01/27/10 6:21pm Page 5
notion that dissociative symptoms can be triggered through
discontinuity in perceptual environments (in this case, from
VR to objective reality), especially among those prone to ex-
periencing dissociative symptoms.
4
Increasing the person’s
ability to tolerate perceptual discontinuities and adopting a
less rigid stance toward perception has been proposed as a
treatment target for those with DP=DR.
3
However, results suggest that the processes that increase
dissociative symptoms as the result of a VR immersion may
not be just pathological. As noted earlier, dissociative expe-
riences lie on a continuum and may refer to completely nor-
mal imaginative processes like daydreaming. The effects of
VR on dissociative symptoms were not in the clinical range or
even within subclinical levels of dissociative experiences. The
effects observed in the current study may be similar to
spending several hours working at a computer and tempo-
rarily feeling more detached from objective reality than usual.
It appears likely that the effects of exposure to VR disappear
rapidly following subsequent immersion into objective real-
ity. In addition, the dissociative effect itself may be dependent
on the duration of VR exposure. Future studies need to shed
light on the duration of the effect by following up with par-
ticipants after VR exposure.
Nonetheless, it is possible that prolonged periods of dis-
continuity in objective perception may have harmful effects
in vulnerable individuals. There are reports in popular
media on Internet and computer game addiction being as-
sociated with neglect and suicide, sometimes inexplicably
so.
23,24
Of course, these anecdotal reports await further in-
vestigation, but the current findings may have bearing on
such incidences if exposure to highly absorbing experiences
such as Internet activity lead to a sense of detachment, a
lowered sense of presence, and potentially an increase in
depressive feelings.
25
Another potential implication of the current results lies in
the use of VR environments to treat anxiety disorders with
gradual exposure.
26
Those with higher preexisting levels of
dissociative symptoms appeared to be more vulnerable to
increases in symptoms of DP=DR as the result of VR. While
the magnitude of these effects are unclear and may last for
only a short duration after exposure to VR, it would be wise
to take those results into consideration when using VR im-
mersions with people who have preexisting clinical levels of
dissociation. Alternatively, a controlled increase in symptoms
of DP=DR could be viewed as a potential avenue for therapy,
including the use of VR in exposing the individual to tran-
sient symptoms of DP=DR and correcting catastrophic mis-
interpretations of symptoms through cognitive-behavior
therapy.
6
One limitation of the current study is the use of a non-
clinical sample and a relatively small sample size. The current
results provide only a preliminary account of the effects of VR
on dissociative experiences and sense of presence in objective
reality. In particular, the effects of VR on dissociative expe-
riences appear to be exacerbated by higher preexisting levels
of dissociation and the individual’s propensity for immer-
sion. Sense of presence in objective reality seems to suffer as
well. Future research should establish the exact relationships
among these variables as well as the exact clinical implica-
tions of the current findings.
Acknowledgments
The study was supported with a Fellowship Award from
the Fonds de la Recherche en Sante
´du Quebec (FRSQ) to the
first author and Grant No. MOP67059 from the Canadian
Institutes of Health Research (CIHR) to the second author.
Disclosure Statement
No competing financial interests exist.
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Address correspondence to:
Dr. Frederick Aardema
Fernand-Seguin Research Center
7331 Hochelaga
Montre
´al, Que
´bec
H1N 3V2 Canada
E-mail: faardema@crfs.rtss.qc.ca
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