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Case Report
Psychopathology 2005;38:144–150
DOI: 10.1159/000085845
‘Internet Delusions’: A Case Series and
Theoretical Integration
Vaughan Bell
a
Ethan Grech
b
Cara Maiden
b
Peter W. Halligan
a
Hadyn D. Ellis
a
a
School of Psychology, Cardiff University, and
b
Cardiff and Vale NHS Trust, Cardiff , UK
en the rich sources of information available, they may be
well suited to treatment with cognitive behavioural ther-
apy.
Copyright © 2005 S. Karger AG, Basel
Introduction
The widespread public availability of the internet has
brought about signifi cant changes to commerce and social
communication. It is now a standard method of commu-
nication for many and is regularly referenced in commer-
cials, news stories and academic study. It is not surprising
therefore, that delusions have been reported in the psy-
chiatric literature in which the internet has featured as a
central theme (see table 1 ). Broad sociocultural infl uenc-
es on delusional beliefs are well known and previous re-
search has shown an infl uence on the presentation of de-
lusions depending on country [9–12] , gender and social
class [13] and social environment [14] . Considering that
the DSM-IV diagnostic criteria for a belief to be consid-
ered delusional are culturally relative (one of the criterion
being that the belief ‘is not one ordinarily accepted by
other members of the person’s culture or subculture’
[15]
), it is perhaps unsurprising that cultural factors might
cause differences in the prevalence of certain themes be-
tween localised populations.
Key Words
Internet delusion Cultural infl uences Pathoplasticity
Collaborative empiricism
Abstract
Background: Delusions involving the internet have been
reported as examples of the infl uence of cultural innova-
tions on delusion formation, although there has been
some debate as to whether such innovations simply af-
fect surface content, or whether they have more substan-
tial clinical or psychopathological implications. Sam-
pling and Methods: Four cases of patients with delusions
involving the internet were identifi ed following a gen-
eral request to local consultant psychiatrists for referrals.
Results: The internet had a specifi c effect on aetiology in
one case, and knowledge of the internet seemed to con-
strain the type of delusion formed in two others. The
presence of an internet-related delusion in the fi nal case
was used to frame a successful clinical intervention
based on the ‘collaborative empiricism’ method, using
cognitive behavioural therapy and collaborative use of
the internet to resolve the delusional belief. Conclusions:
Cultural technical innovations may have specifi c infl u-
ences on the form, origin and content of delusional be-
liefs. For some patients the presence of internet-themed
delusions may be a good prognostic indicator since, giv-
Received: June 11, 2004
Accepted after revision: November 30, 2004
Published online: May 19, 2005
Vaughan Bell
School of Psychology, Cardiff University
Park Place, Cardiff, CF10 3YG (UK)
Tel. +44 29 2087 6504, Fax +44 29 2087 4858
E-Mail BellV1@cardiff.ac.uk
© 2005 S. Karger AG, Basel
0254–4962/05/0383–0144$22.00/0
Accessible online at:
www.karger.com/psp
Internet Delusions
Psychopathology 2005;38:144–150
145
More intriguing have been reports of people whose
delusions have incorporated recent cultural and/or tech-
nical innovations. Several reports of ‘rock and roll’ delu-
sions have been reported, where patients have believed
themselves to be owed money by, persecuted by, or in a
romantic relationship with specifi c and recently popular
musicians or singers [16–18] . More specifi c still, Forsyth,
Harland et al. [19] reported on a patient with the delu-
sional belief that he was a character in a particular com-
puter game. Notably, the game in question was released
only a short time before the report was published. There
is no clear understanding of how long it takes for cultural
innovations to infl uence delusional beliefs, although as
can be seen from fi gure 1 , delusions about the internet
were not reported until the internet was discussed quite
widely in national publications, suggesting, not surpris-
ingly, that a level of cultural salience (or perhaps social
concern) has to be achieved before such concepts typi-
cally become incorporated into paranoid or psychotic ex-
periences.
Commenting on the case of ‘computer game delu-
sions’, Spence [20] argued that such themes, however, are
simply a surface change to the same ‘underlying biologi-
cal signal’, echoing Jaspers’ [21] distinction between form
Table 1. Previous reports of delusions about the internet from the psychiatric literature
Reference Age Sex Psychiatric history Reported delusions
Tan et al. [1] 27 M Body dysmorphic
disorder
Feeling that his life was being controlled by the internet,
concern about ‘double-talk on the internet’, neighbour
putting information about his life online.
Catalano et al. [2]
Case 1 40 M None reported Sexual photographs and video of him/girlfriend on internet,
mind and body control by ‘internet bugs’ and ‘links’ from a
web page.
Case 2 41 M None reported Believed he was a witch and ran an online service for witches
and could ‘surf the net using only his mind’. Received
‘magnetism’ from the internet each day.
Podoll et al. [3]
Case 1 32 M 1st presentation Receiving messages over the internet threatening to expose
his use of internet pornography.
Case 2 19 M 1st presentation Bill Gates was destroying his fi les, spying and following him.
Personal fi les were duplicating themselves and being
broadcast over the internet beyond his control.
Kobayashi et al. [4] 57 F Schizoaffective disorder Heard commanding voices from two men, sent via radio
waves originally emanating from a satellite and transmitted
through the internet.
Duggal et al. [5] 31 M Paranoid schizophrenia Sister-in-law was controlling his thoughts and actions,
sending voices and reading his thoughts through the internet.
Margolese et al. [6] 26 M Schizophrenia People follow his activities via internet chat-rooms devoted
to him and several well-known web sites are dedicated to
him because of similarities with his name and theirs.
Compton [7]
Case 1 53 F ‘Previous hospitalisation’ Internet controlling her (via implanted microchips) and
home appliances for past 3 years.
Case 2 21 F 1st presentation Photographs and recordings of her were being broadcast on
the internet.
Case 3 64 F 1st presentation Being followed by ‘www’ (World Wide Web) people.
Schmid-Siegel et al. [8] 36 F Paranoid schizophrenia Activities were being broadcast via webcam to the internet.
Chip implanted in her brain broadcasts everything she saw
on the internet.
Bell/Grech/Maiden/Halligan/Ellis
Psychopathology 2005;38:144–150
146
and content in psychopathology [Spence, pers. commu-
nic.]. In this formulation, an infl uence on the psycho-
pathological form would entail a change to the phenom-
enological structure of an experienced symptom, includ-
ing the type of psychological constructs involved (e.g.
beliefs, perceptions, thoughts). Conversely, an infl uence
on psychopathological content suggests a difference in the
colouring of experience, for example, affecting exactly
what is delusionally believed or hallucinated. The psycho-
pathological form is the basis upon which psychiatric di-
agnosis is made, having implications for prognosis and
treatment, whereas the content is largely considered ir-
relevant in deciding upon such matters [22] .
Reports of delusions about the internet, however, may
suggest that cultural and environmental infl uences can
represent more than superfi cial substitutions in content,
with the internet in particular having an infl uence on psy-
chopathological form and aetiology, and being important
for decisions on treatment methodology.
As can be seen from a review of published cases ( table
1 ), delusions involving the internet can vary considerably
in presentation. It is notable that the role of the internet
in such delusional beliefs is largely restricted to two major
themes. The fi rst is the use of the internet as an explana-
tory tool to account for unusual experiences, such as ex-
periences of control, voice hearing or having one’s
thoughts read. This phenomenon was fi rst noted by Tausk
[23] in his seminal paper ‘On the Origin of the Infl uenc-
ing Machine in Schizophrenia’, where he noted that tech-
nology is often present as an explanatory device in psy-
chosis and takes the form of a diabolical machine, just
outside the technical understanding of the subject, usu-
ally claimed to be operated by enemies or persecutors of
the affected person. Catalano et al. [2] have argued that
a lack of knowledge about the relevant technology may
fuel internet-themed delusions, perhaps leading to the in-
ternet increasingly appearing as a modern-day incarna-
tion of Tausk’s ‘infl uencing machine’.
A second theme is the supposed use of the internet by
people who are thought to be conspiring against the af-
fected person. Note here that the internet is not repre-
sented as having a direct malign infl uence, but typically
is thought as a means of hosting chat rooms, photos or
recordings about the person concerned. Although delu-
sional ‘bizarreness’ is not a concept without diffi culties
[24], the difference between these two themes perhaps
refl ects the distinction between bizarre (impossible) and
non-bizarre (possible but false) delusions, although per-
haps further technological breakthrough might render de-
lusions previously considered bizarre as simply false.
Whether such differences account for more than the
trivial incorporation of themes into an otherwise well es-
tablished psychopathological process remains a matter of
debate. Stompe et al. [25] argued that sociocultural infl u-
Fig. 1. Mentions of the Internet in The
Times and Sunday Times from 1993 to
2003 and number of cases of reported ‘in-
ternet delusions’ in the medical literature.
Internet Delusions
Psychopathology 2005;38:144–150
147
ences on delusional presentation can be broken down into
a number of levels all of which, in different ways, could
be susceptible to the infl uences of cultural and social set-
ting. They argue that technological innovations only af-
fect the fi nal stages (‘concretization’) of a multi-stage
pathological process that culminates in the formation of
a delusion; therefore, like Spence, they suggest that the
infl uence of a technology such as the internet is relatively
unimportant as an aetiological factor in psychosis.
In contrast, Catalano et al. [9] suggest that ‘internet
delusions’ may represent a ‘new subtype of previously
reported psychiatric illnesses’, echoing similar ideas that
internet addiction may be a novel form of psychopathol-
ogy, due to the internet having unique features which may
lead people into heavy or even compulsive overuse [26,
27] . Other authors have taken somewhat of the middle
ground. Eytan et al. [28] presented two cases of delusions
where patients complained of being implanted with a mi-
crochip and further suggested that such technological de-
lusions may be a form of western culture-bound syn-
drome. The arguments put forward by Catalano et al. [9]
and Eytan et al. [28] seem diffi cult to defend in light of
the fact that they produce little persuasive evidence for a
signifi cant effect of technological innovation on the form,
aetiology or prognosis of the delusions they report. How-
ever, one recent case has suggested that technological
themes may be involved in the development of novel
forms of psychopathology, where previous symptom def-
initions and diagnostic criteria do not fully capture the
obviously aberrant experience.
Schmid-Siegel et al. [8] reported the case of a woman
diagnosed with paranoid schizophrenia who believed
that everything she saw was being broadcast over the in-
ternet. The authors labelled this as ‘perception broadcast’
and noted that, although seeming similar to thought
broadcast, it involved visual perceptions and not
thoughts, and did not involve the direct participation of
others, as the internet was believed to be a mediating
technology and, therefore, did not fulfi l Schneider’s [29]
thought broadcast criteria. In this case, a technological
innovation seems to have infl uenced the psychopatho-
logical form of a psychotic symptom, rather than content
alone.
Furthermore, a case reported by Duggal et al. [5] sug-
gests that the presence of internet-themed delusions may
be a specifi c prognostic indicator. They noted particular
success with using cognitive therapy to treat the delu-
sional belief, largely because of the ease by which reality
testing by ‘collaborative empiricism’ [30] can be used in
therapy. The authors reported that they were able both to
educate their client as to how the internet works (by using
a widely available book) and collaboratively to draw-up
criteria which would potentially disprove the reality of
the client’s delusions. Crucially, they were then able to
directly test these criteria by using the internet to gather
evidence with the client, leading to the rejection of the
delusional belief. The ubiquity of the internet makes it
possible to easily engage in these sorts of reality-testing
tasks, whereas doing the same for delusions concerning
(for example) spirits, magical forces or even microchips
or radio waves, may be diffi cult, if not impossible, to im-
plement practically.
Such cases suggest that technological concepts may
have specifi c infl uences on the aetiology, form and impli-
cations for the clinical management of people with such
delusional beliefs. Wishing to further explore these issues,
we sought to examine locally-occurring cases of internet-
themed delusions.
Patients and Methods
A letter was written to consultant psychiatrists (n = 21) in the
South Wales area, asking for any cases of ‘delusions involving the
internet’ or other recent technological developments. Over a period
of 1 year, 4 such cases were reported to us, which are described be-
low. One further case was reported to us but rejected for inclusion
in this case series as the patient’s initial clinical presentation was
put in doubt after further psychiatric assessment.
Case Reports
Case 1. W.L., a 31-year-old woman with a previous diagnosis
of bipolar affective disorder, was admitted to hospital after being
found in the street in a distressed state. On admission, she recount-
ed how she fi rst felt unwell 6 weeks earlier and became suspicious
when her credit card was refused in a shop, leading to a sense of
unease and increasingly intrusive thoughts. Subsequently, while
examining the packaging of a breath freshening product she noticed
the ingredient ‘phenylalanine’, which she proceeded to use as a
search term on an internet search engine. Her search resulted in
fi nding a webpage, containing many numbers, which outlined ex-
perimental studies on the chemical. Using the most personally sig-
nifi cant numbers from the initial page as search terms she further
found a website explaining an Aramaic system for divining special
meaning from numbers. She suspected this was signifi cant and
came to believe that she had found secret information about the
‘Al-Qaeda’ terrorist network. During the following days she be-
lieved that, because of her discovery of terrorist secrets, her com-
puter and telephone had been tapped in order to monitor her in-
ternet activity and phone calls, and that she was being bugged by
microphones and concealed cameras. W.L. was subsequently diag-
nosed as having a manic episode with psychotic symptoms. She has
had extensive experience using the internet over the previous 10
years and when asked how the internet worked, replied: ‘by linking
computers all over the world using energy and digital technology’.
Bell/Grech/Maiden/Halligan/Ellis
Psychopathology 2005;38:144–150
148
Case 2. K.D., a 42-year-old man, had consulted his GP 5 weeks
earlier for low mood and suspiciousness although he had no previ-
ous contact with mental health services. At interview K.D. claimed
that the websites of several international companies had a ‘darker
side’ and hidden sections that were being used by a secret organisa-
tion. K.D. believed the organisation had blackmailed his wife and
possibly his daughter into involvement with pornography and in-
decent images of them were being distributed across the internet,
partly as a ‘personal vendetta’ against him waged by the two lead-
ers of the organisation. He fi rst suspected that this might be the case
when he saw his wife turn their computer off in a hurry, but believed
that his wife had left a trail of clues for him to fi nd so he could pro-
tect her from danger. The clues were concealed in the names of the
websites which he believed were involved in the conspiracy against
him and his family. A diagnosis of schizophrenia was made during
admission to hospital. K.D. is a competent internet user and had
regularly used email and the web at home over the previous 2 years
for leisure and communicating with friends and family.
Case 3. A.Q., a 36-year-old woman with a previous diagnosis of
bipolar affective disorder, was admitted to hospital concerned that
she was being ‘tracked by cameras’ that had been placed around
her house that were transmitting images of her across radio, televi-
sion and the internet. She was particularly concerned that the in-
ternet was involved as she claimed her daughter had mentioned
that she had seen photographs and videos of her online. A.Q. had
also experienced ‘beams of light’ coming into her house, which she
believed were being controlled via the internet and were involved
in her surveillance. After admission to the hospital ward, she voiced
concerns about being watched by beams of light and was suspicious
of the electric lights in her room. A.Q. was subsequently diagnosed
as having a manic episode with psychotic symptoms. She denied
ever having used the internet before, and when questioned about
how she believed the internet worked she said it operated using
‘beams of light’. When asked in reference to a specifi c example
(sending an email), she said that cables might also be involved.
Case 4. D.S., a 19-year-old male with a previous diagnosis of
schizophrenia and a history of alcohol and substance abuse, was
seen while resident in a hostel shortly after discharge from hospital.
D.S. reported that he believed that the internet was being used to
tell others about a past ‘offence’ (a practical joke he had carried out
on a friend), and that he was followed by ‘thirty to forty’ people
who were disgusted at his past behaviour and wanted to see him
back in hospital. One of the authors of this study (E.G.) engaged
D.S. in cognitive-behavioural therapy to lessen his distress and con-
viction in his delusional beliefs. D.S. rated his conviction that he
was being followed at 90% and his conviction that the internet was
involved was 70–80%. In collaboration with the client, the therapist
used a popular book about the internet and World Wide Web to
explore how they worked, including the use of search engines. It
was established that the minimum information needed to fi nd out
about someone on the internet would be a name and geographical
location. Subsequently, a reality-testing exercise was undertaken
where people of a similar name and location to D.S. were identifi ed
via search engines and the information about them was examined
on-screen, all of which could be confi rmed as being unrelated to
D.S. in any way. His conviction about the internet being involved
in his supposed persecution dropped to 0%, causing him to report
signifi cantly less anxiety and guilt, with the number of people he
supposed were involved in his persecution reduced to ‘ten to
twenty’.
Discussion
The 4 case studies reported here are notable as differ-
ing presentations of internet-themed delusions, or as with
Case 4, an example of how a delusional belief involving
the internet may be resolved in light of Chadwick and
Lowe’s [30] method of reality testing by collaborative em-
piricism.
None of the cases reported here suggests a novel form
of psychotic symptom, as in the case of ‘perception broad-
cast’ reported by Schmid-Siegel et al. [15] . However, Case
1 is of interest because of the individual’s self-reported
use of an internet search engine during the initial stages
of delusion formation. It is quite possible that the content
of the delusion would have been different had another
search engine or method been used as different results
might have been returned, leading to the establishment
of different associations. In this way, the use of the inter-
net may affect the aetiology of delusion formation and
may promote the loosening of associations when used
during a psychotic episode. A jumping-to-conclusions
probabilistic reasoning style has been identifi ed as a fac-
tor in delusion formation [31, 32] , suggesting that even
relatively small amounts of tangential information, which
would not otherwise be encountered, might form the ba-
sis or provide a conducive framework for the formation
of delusional beliefs. K.D. (Case 1) is perhaps a striking
example of this tangential process as she managed to get
from a query about ‘phenylalanine’ to a belief concerning
a terrorist network after only a short period of time. From
this case alone it is not clear whether an effect on the loos-
ening of associations caused by using the internet in this
way would cause the resulting delusion to be any more or
less aberrant, leading to more extreme or, alternatively,
more benign beliefs as a result.
However, it has been noted [33] that people who are
likely to be psychotic may use the internet to form online
communities based around their delusional beliefs and
archive a large corpus of online information to support
their conjectures. Research on the social psychology of
the internet has suggested that people who strongly iden-
tify with a group identity or cause are more likely to have
their attitudes infl uenced to polar extremes if they are not
in the same physical location [34] . Combined with the
increasing availability of domestic internet access and the
fact that ‘on the internet, people who share your interest
and lean in the same direction as you are just a few key-
strokes away, regardless of the issue’s obscurity, social
desirability, or bizarreness’ [35] , people undergoing the
initial stages of psychosis may have delusional beliefs
Internet Delusions
Psychopathology 2005;38:144–150
149
primed, strengthened or deepened by using the internet,
where previously they might have encountered very few
people (if any) who would agree with their interpreta-
tions.
One way of countering potentially disabling delusion-
al beliefs may be through the use of cognitive behavioural
therapy. Both Duggal et al. [12] and the therapist involved
in Case 4 used remarkably similar techniques (although
the therapist reported here was unaware of the work of
Duggal et al. at the time) to implement Chadwick and
Lowe’s [30] collaborative empiricism, with remarkable
success in both cases. The educational aspect of the ther-
apy, where the technological limits of the internet are ex-
plored so the client becomes aware of what the internet
can and cannot do, seems important in shaking the delu-
sional conviction that the internet is involved in their ex-
perience in this case. For example, A.Q. (Case 3) reported
both that the internet was responsible for ‘beams of light’
entering her house, and that the internet relies on beams
of light for its operation. Although this is not entirely in-
accurate (fi bre optic cables provide much of the infrastruc-
ture for large computer networks) it seems in these cases
that an understanding of the technology (or rather, a lack
of understanding) and the delusional explanation are
linked. Scientist and science fi ction author Arthur C.
Clarke [36] noted that for people who do not understand
it, ‘any suffi ciently advanced technology is indistinguish-
able from magic’, implying that poor understanding of a
technology provides greater degrees of freedom in how it
can be used in an ‘explanation’ for an experience or event.
Dispelling ‘magical’ notions about internet technology
would seem to be something which could be easily and
powerfully demonstrated in a therapeutic situation by a
combination of both didactic and interactive exploration
of the internet. This suggests that in cases that involve the
internet as part of a delusional explanation for unusual
experiences, the prognosis may be more hopeful if such
therapeutic techniques are used.
However, as reported in Case 2, not all delusional be-
liefs about the internet may be as easily swayed in this
way if they are not based on a misunderstanding of the
technology. K.D. is notable for having a delusion about
the internet which is not practically falsifi able by educa-
tion about the internet’s workings or by practical use of
the internet. His assertion that there are hidden sections
to major websites is almost certainly accurate, as system
administrators need to be able to log into restricted areas
to administrate the website. In cases such as these, ther-
apy may need to focus on the unlikely nature of the con-
spiracy theory (the likelihood of a sinister organisation
trying to persecute him), rather than the role of technol-
ogy in his delusional explanation. It was notable that K.D.
and W.L. (Case 1) were already competent users and
therefore perhaps less likely to incorporate ‘magical’ ex-
planations of internet function into their concerns. This
suggests that the assertion of Catalano et al. [9] that igno-
rance about the internet may fuel ‘internet delusions’ per
se may be wrong, although an understanding of internet
technology may affect the type of delusional presenta-
tion.
The cases presented here, combined with the previous
reports in the literature, suggest that the internet may not
simply affect a surface change to the same ‘underlying
biological signal’ as Spence [20] claimed, but may infl u-
ence aetiology and form, and have implications for the
clinical management of the resulting symptomatology.
The extent of infl uence may not be equal for all aspects
of society and culture, although the fact that there is an
infl uence at all suggests that psychosis is only fully under-
standable in light of the wider social context. Clinicians
should be aware of the infl uence of the internet on delu-
sional beliefs, as it may occur as a factor in the aetiology
of delusion formation, as a feature of delusion content,
and have implications for the way in which therapy is
framed.
Acknowledgement
The authors would like to thank Professor Mike Owen for his
insightful comments during the preparation of this paper and Fe-
line Siedow for her help with German translation.
Bell/Grech/Maiden/Halligan/Ellis
Psychopathology 2005;38:144–150
150
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