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Virtual reality study of paranoid thinking in the general population

  • Daniel Freeman (a1), Katherine Pugh (a1), Angus Antley (a2), Mel Slater (a3), Paul Bebbington (a4), Matthew Gittins (a5), Graham Dunn (a5), Elizabeth Kuipers (a1), David Fowler (a6) and Philippa Garety (a7)...



Judging whether we can trust other people is central to social interaction, despite being error-prone. A fear of others can be instilled by the contemporary political and social climate. Unfounded mistrust is called paranoia, and in severe forms is a central symptom of schizophrenia.


To demonstrate that individuals without severe mental illness in the general population experience unfounded paranoid thoughts, and to determine factors predictive of paranoia using the first laboratory method of capturing the experience.


Two hundred members of the general public were comprehensively assessed, and then entered a virtual reality train ride populated by neutral characters. Ordinal logistic regressions (controlling for age, gender, ethnicity, education, intellectual functioning, socio-economic status, train use, playing of computer games) were used to determine predictors of paranoia.


The majority agreed that the characters were neutral, or even thought they were friendly. However, a substantial minority reported paranoid concerns. Paranoia was strongly predicted by anxiety, worry, perceptual anomalies and cognitive inflexibility.


This is the most unambiguous demonstration of paranoid ideation in the general public so far. Paranoia can be understood in terms of cognitive factors. The use of virtual reality should lead to rapid advances in the understanding of paranoia.

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Corresponding author

Dr Daniel Freeman, Department of Psychology, PO Box 77, Institute of Psychiatry, King's College London, Denmark Hill, London, SE5 8AF, UK. Email:


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Declaration of interest

None. Funding detailed in Acknowledgements.



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Virtual reality study of paranoid thinking in the general population

  • Daniel Freeman (a1), Katherine Pugh (a1), Angus Antley (a2), Mel Slater (a3), Paul Bebbington (a4), Matthew Gittins (a5), Graham Dunn (a5), Elizabeth Kuipers (a1), David Fowler (a6) and Philippa Garety (a7)...
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The experience of paranoia deserves centre stage

Daniel Freeman, Wellcome Trust Fellow & Consultant Clinical Psychologist
17 April 2008

All too often the presence of paranoid thinking has only been given significance in relation to diagnosing illness. It has been viewed as a symptom that leads to a diagnosis and that, more or less, is the end of it. An alternative view is that the experience itself should take centre stage (1, 2). Persecutory thinking is important to understand and treat inits own right. Evidence is accumulating that paranoid ideation is on a spectrum of severity in the general population. The current study concernsthe milder end of the experience, but it is of interest for understanding clinical paranoia.

Braithwaite's suggestion of an 'erroneous use of the word paranoia' contains an example of the problems of the traditional diagnostic approachto psychosis. The history outlined in the e-letter of the term paranoia was originally described by Sir Aubrey Lewis (3). Lewis began his review of the fluctuations in the use of the word by noting that Hippocrates applied it to describe the delirium of high fever. Braithwaite doesn’t wish to revert to this early use of the term, but takes a very traditionalpsychiatric delusion definition. This view is that paranoia only refers toa fixed false belief that the person cannot conceive of as a symptom. The problems with such a view of delusions have been laid out in many places over many years (4). A simple illustration of the difficulties is providedby asking: how strongly does the idea have to be held to be delusional (100% conviction, 99%, 90% etc)? Studies show that approximately one half of people with clinical delusions can conceive that they might possibly bemistaken. The empirical evidence indicates that delusions are complex multi-dimensional experiences that are not easily dichotomised into being present or absent. The other aspect of the objection is that paranoia can refer to all delusion subtypes. Undoubtedly psychiatric researchers have used the term variably. In our work the definition of the experience beingstudied - called persecutory or paranoid ideation - is made explicit for readers, based upon an earlier review (5). Therefore the most salient point is that the phenomenon being explained is always clear.

The e-letter by Ghosh focuses on one of the predictors of paranoia inVR: previous gaming experience. She provides helpful comment on the association. However there are perhaps more interesting aspects of the study for psychiatry. Persecutory ideation in VR was predicted by everydayoccurrences of paranoid thought, suggesting the results are more generallyapplicable to understanding the paranoia spectrum. Therefore the identification of a number of emotional and cognitive processes (eg. worry, self-esteem, cognitive flexibility) that predict paranoia is where the interest should lie for clinical practice. These factors could be changed and thereby may lead to reductions in persecutory ideation. More broadly, the study highlights the large affective component to paranoid experience. It is hoped that these aspects of the study also generate interest and debate.

(1). Freeman, D., Bentall, R., & Garety, P. (Eds.) (2008). Persecutory Delusions: Assessment, Theory and Treatment. Oxford: Oxford University Press.

(2). Freeman, D. & Freeman, J. (2008). Paranoia: the 21st CenturyFear. Oxford: Oxford University Press.

(3). Lewis, A. (1970). Paranoia and paranoid: a historical perspective. Psychological Medicine, 1, 2 – 12.

(4). Van Os, J. & Verdoux, H. (2003). Diagnosis and classification of schizophrenia: categories versus dimensions, distributions versus disease. In The Epidemiology of Schizophrenia (Editors, R.M. Murray, P.B. Jones, E.Susser, J. van Os, & M. Cannon). pp 364-410. Cambridge: Cambridge University Press.

(5). Freeman, D. & Garety, P.A. (2000). Comments on the content of persecutory delusions: does the definition need clarification? British Journal of Clinical Psychology, 39, 407-414.
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Conflict of interest: None Declared

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Erroneous use of the word "paranoia"

Richard Braithwaite, Specialist Registrar in Adult Psychiatry
15 April 2008

Freeman et al have used an innovative technique in a non-clinical population to confirm a high background prevalence of negative, mistrustful and fearful thoughts about others (1). Their paper may be helpful in encouraging healthcare professionals in their attempts to normalise rather than medicalise such thoughts, which are particularly common and pronounced in patients with neurotic and personality disorders (2).

I am concerned, however, by the authors’ use of the word “paranoia” to describe these thoughts. Freeman et al define paranoia as “the unfounded fear that others intend to cause you harm”, with reference only to an earlier publication by the main author; later in the paper the words“persecutory” and “paranoid” are used synonymously. This definition and usage are erroneous.

Varying definitions of paranoia exist in the literature but the correct meaning of “paranoid” is “delusional” (3). With a Greek derivationand a literal meaning of “out of the mind”, German psychiatrists revived the term in the mid-nineteenth century to describe conditions characterised by delusions, not only of persecution but also of grandeur (4). Later, Kraepelin, Bleuler and others variously attempted to classify paranoia, but central to all concepts was that it referred only to delusional rather than non-delusional ideation, and could include grandiose, jealous or somatic, as well as persecutory, delusions (4). Indeed, the “paranoid” subtype of schizophrenia, still in use presently, refers to an illness dominated by hallucinations and delusions, whilst thelatter need not be persecutory in nature (5).

Of course, over the twentieth century, the word has taken on an entirely different meaning outside psychiatry. Anecdotally, patients frequently report “paranoia” as an unpleasant presenting complaint, despite the fact that, by its very nature, a fixed false belief cannot be viewed by its sufferer as a symptom. Similarly, mental health professionals commonly use the term erroneously, sometimes resulting in non-psychotic patients being inappropriately referred to specialist services for those with psychosis. I fear that Freeman et al’s rejection of the longstanding psychiatric definition of paranoia, in favour of its lay meaning, will only add to this unnecessary confusion.

1.Freeman D, Pugh K, Antley A, Slater M, Bebbington P, Gittins M, Dunn G, Kuipers E, Fowler D, Garety P. Virtual reality study of paranoid thinking in the general population. British Journal of Psychiatry 2008; 192: 258-63.

2.Reid W H, Thorne S A. Personality disorders and violence potential. Journal of Psychiatric Practice 2007; 13: 261-8.

3.Hamilton, M (Ed). Fish’s Clinical Psychopathology (2nd Edition). Butterworth-Heinemann, 1985.

4.Gelder M, Gath D, Mayou R, Cowen, P. Oxford Textbook of Psychiatry(2nd Edition). Oxford University Press, 1996.

5.World Health Organisation. The ICD-10 Classification of Mental andBehavioural Disorders: Clinical Descriptions and Diagnostic Guidelines. World Health Organisation, 1992.

Declaration of interest: None

Richard BraithwaiteSpecialist Registrar in Adult PsychiatryPortsmouth City Teaching Primary Care TrustCavendish House18 Victoria Road SouthSouthseaHampshirePO5 2BZ

Tel: 023 9229 1867Fax: 023 9287 2932
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Virtual Reality: A neutral environment for computer game playing population?

Sunanda Ghosh, Specialty Registrar 4
09 April 2008

The use of virtual reality to create a 'laboratory' is promising. As someone who has played computer games and has used the Tube almost daily for four years, I was interested in the observations that those who used the tube regularly were less likely to have persecutory thinking in virtual reality, while an experience of playing computer games was a strong predictor of paranoid thinking.

I am not sure if the observations can be justified by an assumption that the game-playing individuals were reacting because they automaticallyprocessed the computer characters as real. The use of a virtual reality environment may have introduced a bias not taken into account just by estimating the duration of game play.

Cognition and automatic thoughts are based on prior experiences. Has this study taken into account how prior gaming experience may affect one'sperception to a virtual reality environment, as opposed to a generalised cognition easily translated to the real world? Is there a possibility thatthey automatically processed the environment as being hostile thus making the findings 'a strong predictor of paranoid thinking' only in a virtual world?

The data provided in the paper fails to show the nature of gaming experience these people have had. Is it possible that a person who plays non violent strategy games, or gambles online will have a different experience of virtual reality as compared to someone who plays first person shooters where one of the primary objectives of the game would be to survive, keep safe distance and of course, to 'kill' other players whenthey are in range? Also, would the findings be different if some of these people who played computer games spent their time in virtual reality social networking worlds such as 'Second Life'?

If an experience of travelling in the tube regularly shows less likelihood of feeling persecuted in a virtual train ride, can it be said that a prior experience of threatening virtual reality environment make those who play games more likely to feel persecuted in the chosen medium than they would otherwise be in the real life?
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