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Writings relating to pathological lying first appeared in the psychiatric literature over 100 years ago and have been given names such as "pseudologia fantastica" and "mythomania" and often used interchangeably. There is some consensus that Dr. Anton Delbruck, a German physician, was the first person to describe the concept of pathological lying in 1891 after publishing an account of five of his patients.
Despite the long history of research, pathological lying is not included in either the American Psychiatric Association’s Diagnostic and Statistical Manual (DSM-5) or the World Health Organization’s International Classification of Diseases (ICD-10). The only mention of pathological lying in the DSM is in association with Factitious Disorder (discussed below), however, many psychologists and psychiatrists claim that it is a distinct psychiatric disorder, as highlighted in the many papers that have been published on the topic over the last two decades.
At a very simplistic level, pathological lying refers to a person that incessantly tells lies. However, Dr. Charles Dike and his colleagues in a 2005 issue of the Journal of the American Academy of Psychiatry and Law define it as "falsification entirely disproportionate to any discernible end in view, may be extensive and very complicated, and may manifest over a period of years or even a lifetime, in the absence of definite insanity, feeble-mindedness or epilepsy."
However, there are other psychiatric conditions (such as people with manipulative personality) that may also engage in pathological lying as part of a wider set of behaviours and symptoms. In fact, there is a lot of debate as to whether the behaviour is really a discrete and unique entity or whether it typically manifests itself as an adjunct to other recognized psychological and/or psychiatric conditions. Dr. Dike and colleagues note that:
“Pathological liars can believe their lies to the extent that, at least to others, the belief may appear to be delusional; they generally have sound judgment in other matters; it is questionable whether pathological lying is always a conscious act and whether pathological liars always have control over their lies; an external reason for lying (such as financial gain) often appears absent and the internal or psychological purpose for lying is often unclear; the lies in pathological lying are often unplanned and rather impulsive; the pathological liar may become a prisoner of his or her lies; the desired personality of the pathological liar may overwhelm the actual one; pathological lying may sometimes be associated with criminal behavior; the pathological liar may acknowledge, at least in part, the falseness of the tales when energetically challenged; and, in pathological lying, telling lies may often seem to be an end in itself. However, it is evident that no single descriptive tableau of a pathological liar settles all the nosological and etiological questions raised by the phenomenon of pathological lying.” (p.344)
Dike and colleagues then went on to list a wide range of psychiatric conditions that have been associated with pathological lying in an attempt to contextualize how the lying behaviour is manifested within these known conditions. The list of psychological and psychiatric conditions included: (i) Malingering, (ii) Confabulation, (iii) Ganser’s Syndrome, (iv) Factitious Disorder, (v) Borderline Personality Disorder, (vi) Antisocial Personality Disorder, (vii) Histrionic Personality Disorders. Arguably, it is these last three disorders with which pathological lying is most associated. The following briefly describes the symptoms and context of each of these conditions as outlined by Dr. Dike and his colleagues:
- Malingering: This is deliberate lying where the person grossly exaggerates or totally lies about physical and/or psychological symptoms. Unlike "archetypal" pathological liars, malingerers are typically motivated to tell lies for a specific purpose, such as to obtain financial compensation, to avoid working, to avoid military service, to avoid criminal prosecution, etc.
- Confabulation: This is where people tell lies incessantly as a way of covering up memory lapses caused by specific memory loss conditions (e.g., organically derived amnesia). In archetypal pathological liars, the condition is psychological (rather than organic) in origin.
- Ganser’s Syndrome (GS): GS is a rare dissociative disorder (only 101 recorded cases ever) characterized by affected people giving nonsensical answers to questions (and goes under many other names including "nonsense syndrome" and "balderdash syndrome"). Unlike the elaborate and sometimes fantastical stories told by archetypal pathological liars, the lies told by those with GS are very simplistic and approximate.
- Factitious Disorder (FD): FD is the deliberate use of lies and/or exaggerations concerning psychological and/or physical symptoms solely for the purpose of assuming the role of a sick person (formerly known as Munchausen’s Syndrome). In contrast, the archetypal pathological liar doesn’t want to appear sick to other people.
- Borderline Personality Disorder (BPD): BPD is a condition where people have long-term patterns of unstable and/or turbulent emotions. Pathological lying and being deceitful are not core characteristics of BPD, according to the DSM, but some with BPD do engage in lies. BPD patients typically lack a consistent self-identity and impulse control, which may facilitate the distortions or lies told.
- Antisocial Personality Disorder (APD): APD is the condition in which the sufferer has a long-term pattern of manipulating, exploiting, or violating the rights of others (and is often criminal). Those with APD often lie repeatedly and consistently for personal satisfaction alone. Although those with APD are often pathological liars, archetypal pathological liars rarely have disordered antisocial personalities.
- Histrionic Personality Disorder (HPD): Those with HPD act in a highly emotional and dramatic way to draw attention to themselves. They often lie as a way to enhance and/or facilitate their dramatic and attention-seeking behaviour. In contrast, archetypal pathological liars do not constantly seek attention.
Based on the list above, it is evident that the symptom of pathological lying can occur in some mental disorders (e.g., FD) and could be called secondary pathological lying. However, it is much less clear whether it can occur independently of a known psychiatric disorder and be seen as primary pathological lying. Unlike the other forms of lying outlined above, Dr. Dike says pathological lying appears to be unplanned and impulsive. Despite all the speculation, there is still relatively little known, although it’s thought to affect men and women equally, with an onset in late adolescence. There are no reliable prevalence figures, although one study estimated that one in 1,000 repeat juvenile offenders suffered from it.
On a biological and neurological level, a paper published in the Journal of Neuropsychiatry and Clinical Neurosciences by Dr. J.G. Modell and colleagues reported the case of a pathological liar who was given a brain scan. Results showed that his condition was associated with right hemithalamic dysfunction. This supported the hypothesized roles of the thalamus and associated brain regions in the modulation of behavior and cognition.
A 2007 study published in the British Journal of Psychiatry by Dr. Y. Yang and colleagues reported differences in brain structure between pathological liars and control groups. Pathological liars showed a relatively widespread increase in white matter (approximately one-quarter to one-third more than controls) and the authors suggested that this increase may predispose some individuals to pathological lying.
Those working in the mental health system need to pay attention to pathological lying so that they can inform legal practitioners about whether pathological liars should be held responsible for their behaviour. Whether pathological liars are aware of the lies they tell has major implications for forensic psychiatry practice. Dr. Dike says it could help determine how a court deals with pathological liars who provide false testimony while under oath.
