Conversion disorder (CD) is a diagnostic category used in some psychiatric classification systems. It is sometimes applied to patients who present with neurological symptoms, such as numbness, blindness, paralysis, or fits, which are not consistent with a well-established organic cause, which cause significant distress, and can be traced back to a psychological trigger. It is thought that these symptoms arise in response to stressful situations affecting a patient's mental health or an ongoing mental health condition such as depression. Conversion disorder was retained in DSM-5, but given the subtitle functional neurological symptom disorder. The new criteria cover the same range of symptoms, but remove the requirements for a psychological stressor to be present and for feigning to be disproved.
The theory of conversion disorder stems from ancient Egypt, and was formerly known as hysteria and hysterical blindness. The concept of conversion disorder came to prominence at the end of the 19th century, when the neurologists Jean-Martin Charcot and Sigmund Freud and psychologist Pierre Janet focused their studies on the subject. Before their studies, people with hysteria were often believed to be malingering. The term "conversion" has its origins in Freud's doctrine that anxiety is "converted" into physical symptoms. Though previously thought to have vanished from the West in the 20th century, some research has suggested that conversion disorder is as common as ever.
|Treatment||CBT, antidepressants, physical/occupational therapy|
Conversion disorder begins with some stressor, trauma, or psychological distress. Usually the physical symptoms of the syndrome affect the senses or movement. Common symptoms include blindness, partial or total paralysis, inability to speak, deafness, numbness, difficulty swallowing, incontinence, balance problems, seizures, tremors, and difficulty walking. These symptoms are attributed to conversion disorder when a medical explanation for the afflictions cannot be found. Symptoms of conversion disorder usually occur suddenly. Conversion disorder is typically seen in individuals aged 10 to 35, and affects between 0.011% and 0.5% of the general population.
Conversion disorder can present with motor or sensory symptoms including any of the following:
Motor symptoms or deficits:
Sensory symptoms or deficits:
Conversion symptoms typically do not conform to known anatomical pathways and physiological mechanisms. It has sometimes been stated that the presenting symptoms tend to reflect the patient's own understanding of anatomy and that the less medical knowledge a person has, the more implausible are the presenting symptoms. However, no systematic studies have yet been performed to substantiate this statement.
Conversion disorder is now contained under the umbrella term functional neurological symptom disorder. In cases of conversion disorder, there is a psychological stressor.
The diagnostic criteria for functional neurological symptom disorder, as set out in DSM-5, are:
Specify type of symptom or deficit as:
Conversion disorder presents with symptoms that typically resemble a neurological disorder such as stroke, multiple sclerosis, epilepsy or hypokalemic periodic paralysis. The neurologist must carefully exclude neurological disease, through examination and appropriate investigations. However, it is not uncommon for patients with neurological disease to also have conversion disorder.
In excluding neurological disease, the neurologist has traditionally relied partly on the presence of positive signs of conversion disorder, i.e. certain aspects of the presentation that were thought to be rare in neurological disease but common in conversion. The validity of many of these signs has been questioned, however, by a study showing that they also occur in neurological disease. One such symptom, for example, is la belle indifférence, described in DSM-IV as "a relative lack of concern about the nature or implications of the symptoms". In a later study, no evidence was found that patients with functional symptoms are any more likely to exhibit this than patients with a confirmed organic disease. In DSM-V, la belle indifférence was removed as a diagnostic criteria.
Another feature thought to be important was that symptoms tended to be more severe on the non-dominant (usually left) side of the body. There have been a number of theories about this, such as the relative involvement of cerebral hemispheres in emotional processing, or more simply, that it was "easier" to live with a functional deficit on the non-dominant side. However, a literature review of 121 studies established that this was not true, with publication bias the most likely explanation for this commonly held view. Although agitation is often assumed to be a positive sign of conversion disorder, release of epinephrine is a well-demonstrated cause of paralysis from hypokalemic periodic paralysis.
Misdiagnosis does sometimes occur. In a highly influential study from the 1960s, Eliot Slater demonstrated that misdiagnoses had occurred in one third of his 112 patients with conversion disorder. Later authors have argued that the paper was flawed, however, and a meta-analysis has shown that misdiagnosis rates since that paper was published are around 4%, the same as for other neurological diseases.
Conversion disorder is unique in ICD-10 in explicitly requiring the exclusion of deliberate feigning. Unfortunately, this is likely to be demonstrable only where the patient confesses, or is "caught out" in a broader deception, such as a false identity. One neuroimaging study suggested that feigning may be distinguished from conversion by the pattern of frontal lobe activation; however, this was a piece of research, rather than a clinical technique. True rates of feigning in medicine remain unknown. However, it is believed that feigning of conversion disorder is no more likely than of other medical conditions.
The psychological mechanism of conversion can be the most difficult aspect of a conversion diagnosis. Even if there is a clear antecedent trauma or other possible psychological trigger, it is still not clear exactly how this gives rise to the symptoms observed. Patients with medically unexplained neurological symptoms may not have any psychological stressor, hence the use of the term "functional neurological symptom disorder" in DSM-5 as opposed to "conversion disorder", and DSM-5's removal of the need for a psychological trigger.
There are many number of different treatments that are available to treat and manage conversion syndrome. Treatments for conversion syndrome include hypnosis, psychotherapy, physical therapy, stress management, and transcranial magnetic stimulation. Treatment plans will consider duration and presentation of symptoms and may include one or multiple of the above treatments. This may include the following:
There is little evidence-based treatment of conversion disorder. Other treatments such as cognitive behavioral therapy, hypnosis, EMDR, and psychodynamic psychotherapy, EEG brain biofeedback need further trials. Psychoanalytic treatment may possibly be helpful. However, most studies assessing the efficacy of these treatments are of poor quality and larger, better controlled studies are urgently needed. Cognitive Behavioural Therapy is the most common treatment, however boasts a mere 13% improvement rate.
Empirical studies have found that the prognosis for conversion disorder varies widely, with some cases resolving in weeks, and others enduring for years or decades. There is also evidence that there is no cure for conversion disorder, and that although patients may go into remission, they can relapse at any point. Furthermore, many patients who are 'cured' continue to have some degree of symptoms indefinitely.
Information on the frequency of conversion disorder in the West is limited, in part due to the complexities of the diagnostic process. In neurology clinics, the reported prevalence of unexplained symptoms among new patients is very high (between 30 and 60%). However, diagnosis of conversion typically requires an additional psychiatric evaluation, and since few patients will see a psychiatrist it is unclear what proportion of the unexplained symptoms are actually due to conversion. Large scale psychiatric registers in the US and Iceland found incidence rates of 22 and 11 newly diagnosed cases per 100,000 person-years, respectively. Some estimates claim that in the general population, between 0.011% and 0.5% of the population have conversion disorder.
Although it is often thought that the frequency of conversion may be higher outside of the West, perhaps in relation to cultural and medical attitudes, evidence of this is limited. A community survey of urban Turkey found a prevalence of 5.6%. Many authors have found occurrence of conversion to be more frequent in rural, lower socio-economic groups, where technological investigation of patients is limited and individuals may be less knowledgeable about medical and psychological concepts.
Historically, the concept of 'hysteria' was originally understood to be a condition exclusively affecting women, though the concept was eventually extended to men. In recent surveys of conversion disorder (formerly classified as "hysterical neurosis, conversion type"), females predominate, with between 2 and 6 female patients for every male.
The first evidence of functional neurological symptom disorder dates back to 1900 BC, when the symptoms were blamed on the uterus moving within the female body. The treatment varied "depending on the position of the uterus, which must be forced to return to its natural position. If the uterus had moved upwards, this could be done by placing malodorous and acrid substances near the woman’s mouth and nostrils, while scented ones were placed near her vagina; on the contrary, if the uterus had lowered, the document recommends placing the acrid substances near her vagina and the perfumed ones near her mouth and nostrils."
In Greek mythology, hysteria, the original name for functional neurological symptom disorder, was thought to be caused by a lack of orgasms, uterine melancholy and not procreating. Plato, Aristotle and Hippocrates believed that a lack of sex upset the uterus. The Greeks believed that it could be prevented and cured with wine and orgies. Hippocrates argued that a lack of regular sexual intercourse led to the uterus producing toxic fumes and caused it to move in the body, and that this meant that all women should be married and enjoy a satisfactory sexual life.
From the 13th century, women with hysteria were exorcised, as it was believed that they were possessed by the devil. It was believed that if doctors could not find the cause of a disease or illness, it must be caused by the devil.
At the beginning of the 16th century, women were sexually stimulated by midwives in order to relieve their symptoms. Gerolamo Cardano and Giambattista della Porta believed that polluted water and fumes caused the symptoms of hysteria. Towards the end of the century, however, the role of the uterus was no longer thought central to the disorder, with Thomas Willis discovering that the brain and central nervous system were the cause of the symptoms. Thomas Sydenham argued that the symptoms of hysteria may have an organic cause. He also proved that the uterus is not the cause of symptom.
In 1692, in the US town of Salem, Massachusetts, there was an outbreak of hysteria. This led to the Salem witch trials, where the women accused of being witches had symptoms such as sudden movements, staring eyes and uncontrollable jumping.
During the 18th century, there was a move from the idea of hysteria being caused by the uterus to it being caused by the brain. This led to an understanding that it could affect both sexes. Jean-Martin Charcot argued that hysteria was caused by "a hereditary degeneration of the nervous system, namely a neurological disorder".
In the 19th century, hysteria moved from being considered a neurological disorder to being considered a psychological disorder, when Pierre Janet argued that "dissociation appears autonomously for neurotic reasons, and in such a way as to adversely disturb the individual's everyday life". However, as early as 1874, doctors including W. B. Carpenter and J. A. Omerod began to speak out against the hysteria phenomenon as there was no evidence to prove its existence.
Sigmund Freud referred to the condition as both hysteria and conversion disorder throughout his career. He believed that those with the condition could not live in a mature relationship, and that those with the condition were unwell in order to achieve a "secondary gain", in that they are able to manipulate their situation to fit their needs or desires. He also found that both men and women could suffer from the disorder.
Freud's model suggested that the emotional charge deriving from painful experiences would be consciously repressed as a way of managing the pain, but that the emotional charge would be somehow "converted" into neurological symptoms. Freud later argued that the repressed experiences were of a sexual nature. As Peter Halligan comments, conversion has "the doubtful distinction among psychiatric diagnoses of still invoking Freudian mechanisms".
Pierre Janet, the other great theoretician of hysteria, argued that symptoms arose through the power of suggestion, acting on a personality vulnerable to dissociation. In this hypothetical process, the subject's experience of their leg, for example, is split off from the rest of their consciousness, resulting in paralysis or numbness in that leg.
Later authors have attempted to combine elements of these various models, but none of them has a firm empirical basis. In 1908, Steyerthal predicted that: "Within a few years the concept of hysteria will belong to history ... there is no such disease and there never has been. What Charcot called hysteria is a tissue woven of a thousand threads, a cohort of the most varied diseases, with nothing in common but the so-called stigmata, which in fact may accompany any disease." However, the term "hysteria" was still being used well into the 20th century.
Some support for the Freudian model comes from findings of high rates of childhood sexual abuse in conversion patients. Support for the dissociation model comes from studies showing heightened suggestibility in conversion patients. However, critics argue that it can be challenging to find organic pathologies for all symptoms, and so the practice of diagnosing patients who suffered with such symptoms as having hysteria led to the disorder being meaningless, vague and a sham diagnosis, as it does not refer to any definable disease. Furthermore, throughout its history, many patients have been misdiagnosed with hysteria or conversion disorder when they had organic disorders such as tumours or epilepsy or vascular diseases. This has led to patient deaths, a lack of appropriate care and suffering for the patients. Eliot Slater, after studying the condition in the 1950s, stated: "The diagnosis of 'hysteria' is all too often a way of avoiding a confrontation with our own ignorance. This is especially dangerous when there is an underlying organic pathology, not yet recognised. In this penumbra we find patients who know themselves to be ill but, coming up against the blank faces of doctors who refuse to believe in the reality of their illness, proceed by way of emotional lability, overstatement and demands for attention ... Here is an area where catastrophic errors can be made. In fact it is often possible to recognise the presence though not the nature of the unrecognisable, to know that a man must be ill or in pain when all the tests are negative. But it is only possible to those who come to their task in a spirit of humility. In the main the diagnosis of 'hysteria' applies to a disorder of the doctor–patient relationship. It is evidence of non-communication, of a mutual misunderstanding ... We are, often, unwilling to tell the full truth or to admit to ignorance ... Evasions, even untruths, on the doctor’s side are among the most powerful and frequently used methods he has for bringing about an efflorescence of 'hysteria'".
Much recent work has been done to identify the underlying causes of conversion and related disorders and to better understand why conversion disorder and hysteria appear more commonly in women. Current theoreticians tend to believe that there is no single cause for these disorders. Instead, the emphasis tends to be on the individual understanding of the patient and a variety of therapeutic techniques. In some cases, the onset of conversion disorder correlates to a traumatic or stressful event. There are also certain populations that are considered at risk for conversion disorder, including people suffering from a medical illness or condition, people with personality disorder, and individuals with dissociative identity disorder. However, no biomarkers have yet been found to support the idea that conversion disorder is caused by a psychiatric condition.
There has been much recent interest in using functional neuroimaging to study conversion. As researchers identify the mechanisms which underlie conversion symptoms, it is hoped that they will enable the development of a neuropsychological model. A number of such studies have been performed, including some which suggest that the blood-flow in patients' brains may be abnormal while they are unwell. However, the studies have all been too small to be confident of the generalisability of their findings, so no neuropsychological model has been clearly established.
An evolutionary psychology explanation for conversion disorder is that the symptoms may have been evolutionarily advantageous during warfare. A non-combatant with these symptoms signals non-verbally, possibly to someone speaking a different language, that she or he is not dangerous as a combatant and also may be carrying some form of dangerous infectious disease. This can explain that conversion disorder may develop following a threatening situation, that there may be a group effect with many people simultaneously developing similar symptoms (as in mass psychogenic illness), and the gender difference in prevalence.
The Lacanian model accepts conversion disorder as a common phenomenon inherent in specific psychical structures. The higher prevalence of it among women is based on somewhat different intrapsychic relations to the body from those of typical males, which allows the formation of conversion symptoms.
Anthony Feinstein (born December 14, 1956) is a Professor of Psychiatry at the University of Toronto and a neuropsychiatrist. His research and clinical work focuses on people with multiple sclerosis, traumatic brain injury and Conversion Disorder. He has undertaken a number of studies investigating how front-line journalists are affected by their work covering war and man-made and natural disasters.Astasia-abasia
Astasia-abasia refers to the inability to either stand or walk in a normal manner. Astasia refers to the inability to stand upright unassisted. Abasia refers to lack of motor coordination in walking. The term abasia literally means that the base of gait (the lateral distance between the two feet) is inconstant or unmeasurable. When seen in conversion disorder, the gait is bizarre and is not suggestive of a specific organic lesion: often the patient sways wildly and nearly falls, recovering at the last moment.
An acquired total inability to stand and walk can be seen in true neurological diseases, including stroke, Parkinson's disease, damage to the cerebellum, Guillain–Barré syndrome, normal pressure hydrocephalus and many others. In normal pressure hydrocephalus, for example, when the condition remains untreated, the patient's gait becomes shortened, with frequent shuffling and falls; eventually standing, sitting, and even rolling over in bed become impossible. This advanced state is referred to as "hydrocephalic astasia-abasia".Dissociation (psychology)
Dissociation is any of a wide array of experiences from mild detachment from immediate surroundings to more severe detachment from physical and emotional experiences. The major characteristic of all dissociative phenomena involves a detachment from reality, rather than a loss of reality as in psychosis.Dissociation is commonly displayed on a continuum. In mild cases, dissociation can be regarded as a coping mechanism or defense mechanisms in seeking to master, minimize or tolerate stress – including boredom or conflict. At the nonpathological end of the continuum, dissociation describes common events such as daydreaming. Further along the continuum are non-pathological altered states of consciousness.More pathological dissociation involves dissociative disorders, including dissociative fugue and depersonalization disorder with or without alterations in personal identity or sense of self. These alterations can include: a sense that self or the world is unreal (depersonalization and derealization); a loss of memory (amnesia); forgetting identity or assuming a new self (fugue); and separate streams of consciousness, identity and self (dissociative identity disorder, formerly termed multiple personality disorder) and complex post-traumatic stress disorder.Dissociative disorders are sometimes triggered by trauma, but may be preceded only by stress, psychoactive substances, or no identifiable trigger at all. The ICD-10 classifies conversion disorder as a dissociative disorder. The Diagnostic and Statistical Manual of Mental Disorders groups all dissociative disorders into a single category.Although some dissociative disruptions involve amnesia, other dissociative events do not. Dissociative disorders are typically experienced as startling, autonomous intrusions into the person's usual ways of responding or functioning. Due to their unexpected and largely inexplicable nature, they tend to be quite unsettling.Dissociative disorder
Dissociative disorders (DD) are conditions that involve disruptions or breakdowns of memory, awareness, identity, or perception. People with dissociative disorders use dissociation as a defense mechanism, pathologically and involuntarily. Some dissociative disorders are triggered by psychological trauma, but dissociative disorders such as depersonalization/derealization disorder may be preceded only by stress, psychoactive substances, or no identifiable trigger at all.The dissociative disorders listed in the American Psychiatric Association's DSM-5 are as follows:
Dissociative identity disorder (formerly multiple personality disorder): the alternation of two or more distinct personality states with impaired recall among personality states. In extreme cases, the host personality is unaware of the other, alternating personalities; however, the alternate personalities can be aware of all the existing personalities. This category now includes the old derealization disorder category.
Dissociative amnesia (formerly psychogenic amnesia): the temporary loss of recall memory, specifically episodic memory, due to a traumatic or stressful event. It is considered the most common dissociative disorder amongst those documented. This disorder can occur abruptly or gradually and may last minutes to years depending on the severity of the trauma and the patient.
Dissociative fugue (formerly psychogenic fugue) is now subsumed under the dissociative amnesia category. It is described as reversible amnesia for personal identity, usually involving unplanned travel or wandering, sometimes accompanied by the establishment of a new identity. This state is typically associated with stressful life circumstances and can be short or lengthy.
Depersonalization disorder: periods of detachment from self or surrounding which may be experienced as "unreal" (lacking in control of or "outside" self) while retaining awareness that this is only a feeling and not a reality.
Dissociative seizures also known as psychogenic non-epileptic seizures: seizures that are often mistaken for epilepsy but are not caused by electrical pulses in the brain and are in fact another form of dissociation. https://www.epilepsyqueensland.com.au/psychogenic-non-epileptic-seizures
The old category of dissociative disorder not otherwise specified is now split into two: Other specified dissociative disorder, and unspecified dissociative disorder. These categories are used for forms of pathological dissociation that do not fully meet the criteria of the other specified dissociative disorders, or if the correct category has not been determined.Both dissociative amnesia and dissociative fugue usually emerge in adulthood and rarely occur after the age of 50. The ICD-10 classifies conversion disorder as a dissociative disorder while the DSM-IV classifies it as a somatoform disorder.Functional neurological symptom disorder
A functional neurological disorder (FND) is a condition in which patients experience neurological symptoms such as weakness, movement disorders, sensory symptoms and blackouts. The brain of a patient with functional neurological symptom disorder is structurally normal, but functions incorrectly. According to consensus from the literature and from physicians and psychologists practicing in the field, functional symptoms are also called 'medically unexplained'. Historically, other terms have been used to describe these symptoms. Symptoms of functional neurological disorders are clinically recognisable, but are not categorically associated with a definable organic disease. The intended contrast is with an organic brain syndrome, although the terms imply a level of certainty about causation that is often clinically unconfirmed. Subsets of functional neurological disorders include functional neurological symptom disorder (FNsD), conversion disorder, and psychogenic movement disorder/non-epileptic seizures. Functional neurological disorders are common in neurological services, accounting for up to one third of outpatient neurology clinic attendances, and associated with as much physical disability and distress as other neurological disorders.
The diagnosis is made based on positive signs and symptoms in the history and examination during consultation of a neurologist (see below). Physiotherapy is particularly helpful for patients with motor symptoms (weakness, gait disorders, movement disorders) and tailored cognitive behavioural therapy has the best evidence in patients with dissociative (non-epileptic) attacks.Ganser syndrome
Ganser syndrome is a rare dissociative disorder characterized by nonsensical or wrong answers to questions and other dissociative symptoms such as fugue, amnesia or conversion disorder, often with visual pseudohallucinations and a decreased state of consciousness. The syndrome has also been called nonsense syndrome, balderdash syndrome, syndrome of approximate answers, hysterical pseudodementia or prison psychosis. The term prison psychosis is sometimes used because the syndrome occurs most frequently in prison inmates, where it may be seen as an attempt to gain leniency from prison or court officials. Psychological symptoms generally resemble the patient's sense of mental illness rather than any recognized category. The syndrome may occur in persons with other mental disorders such as schizophrenia, depressive disorders, toxic states, paresis, alcohol use disorders and factitious disorders. Ganser syndrome can sometimes be diagnosed as merely malingering, but it is more often defined as dissociative disorder.The discovery of Ganser syndrome is attributed to Sigbert Josef Maria Ganser (24 January 1853–4 January 1931). In 1898, he described the disorder in prisoners awaiting trial in a penal institution in Halle, Germany. He named impaired consciousness and distorted communication, namely in the form of approximate answers (also referred to as Vorbeireden in literature), as the defining symptoms of the syndrome. Vorbeireden involves the inability to answer questions precisely, although the content of the questions is understood.Ganser syndrome is described as a dissociative disorder not otherwise specified (NOS) in the DSM-IV, and is not currently listed in the DSM-V. It is a rare and an often overlooked clinical phenomenon. In most cases, it is preceded by extreme stress and followed by amnesia for the period of psychosis. In addition to approximate answers, other symptoms include a clouding of consciousness, somatic conversion disorder symptoms, confusion, stress, loss of personal identity, echolalia, and echopraxia.Glossary of psychiatry
This glossary covers terms found in the psychiatric literature; the word origins are primarily Greek, but there are also Latin, French, German, and English terms. Many of these terms refer to expressions dating from the early days of psychiatry in Croatia.Hoover's sign (leg paresis)
Hoover’s sign of leg paresis is one of two signs named for Charles Franklin Hoover. It is a maneuver aimed to separate organic from non-organic paresis of the leg. The sign relies on the principle of synergistic contraction.Hysteria
Hysteria colloquially means ungovernable emotional excess. Generally, modern medical professionals have abandoned using the term "hysteria" to denote a diagnostic category, replacing it with more precisely defined categories, such as somatization disorder. In 1980, the American Psychiatric Association officially changed the diagnosis of "hysterical neurosis, conversion type" to "conversion disorder".
While the word hysteria originates from the Greek word for uterus, hystera (ὑστέρα), the word itself is not an ancient one, and the term "hysterical suffocation" – meaning a feeling of heat and inability to breathe, was instead used in ancient Greek medicine. This suggests an entirely physical cause for the symptoms but, by linking them to the uterus, suggests that the disorder can only be found in women.Historically, hysteria was thought to manifest itself in women (female hysteria) with a variety of symptoms, including: anxiety, shortness of breath, fainting, insomnia, irritability, nervousness, as well as sexually forward behaviour. These symptoms mimic symptoms of other more definable diseases and create a case for arguing against the validity of hysteria as an actual disease, and it is often implied that it is an umbrella term for an indefinable illness. Through to the 20th century, however, the label hysteria was applied to a mental, rather than uterine or physical, affliction. Hysteria is no longer thought of as a real ailment.In modern usage, the term hysteria connotes mass panic (mass hysteria). Hysteria was often associated with events such as the Salem witch trials, or slave revolt.The term hysterical, applied to an individual, can mean that he or she is emotional or irrationally upset; applied to a situation that does not involve panic, it means that situation is uncontrollably amusing (the connotation being that it invokes hysterical laughter).List of blindness effects
There are several psychological and physiological effects that cause blindness to some visual stimulus.
Banner blindness or ad blindness, consciously or subconsciously ignoring banner-like advertisements at web pages.
Change blindness, the inability to detect some changes in busy scenes.
Choice blindness, a result in a perception experiment by Petter Johansson and colleagues.
Color blindness, a color vision deficiency.
Cortical blindness, a loss of vision caused by damage to the visual area in the brain.
Flash blindness, a visual impairment following exposure to a light flash.
Hysterical blindness (nowadays known as conversion disorder), the appearance of neurological symptoms without a neurological cause.
Inattentional blindness or perceptual blindness, failing to notice some stimulus that is in plain sight.
Motion blindness, a neuropsychological disorder causing an inability to perceive motion.Mass psychogenic illness
Mass psychogenic illness (MPI), also called mass sociogenic illness, mass psychogenic disorder, epidemic hysteria, or mass hysteria, is "the rapid spread of illness signs and symptoms affecting members of a cohesive group, originating from a nervous system disturbance involving excitation, loss, or alteration of function, whereby physical complaints that are exhibited unconsciously have no corresponding organic aetiology".Nosophobia
Nosophobia is the irrational fear of contracting a disease, a type of specific phobia. Primary fears of this kind are fear of contracting HIV, pulmonary tuberculosis, venereal diseases, cancer, and heart diseases.
Some authors have suggested that the medical students' disease should accurately be referred to as "nosophobia" rather than "hypochondriasis", because the quoted studies show a very low percentage of hypochondriacal character of the condition.The word nosophobia comes from the Greek νόσος nosos for "disease".Primary and secondary gain
Primary morbid gain or secondary morbid gain are used in medicine to describe the significant subconscious psychological motivators patients may have when presenting with symptoms. It is important to note that if these motivators are recognized by the patient, and especially if symptoms are fabricated or exaggerated for personal gain, then this is instead considered malingering.
Primary morbid gain produces positive internal motivations. For example, a patient might feel guilty about being unable to perform some task. If a medical condition justifying an inability is present, it may lead to decreased psychological stress. Primary gain can be a component of any disease, but is most typically demonstrated in conversion disorder – a psychiatric disorder in which stressors manifest themselves as physical symptoms without organic causes, such as a person who becomes blindly inactive after seeing a murder. The "gain" may not be particularly evident to an outside observer.
Secondary morbid gain can also be a component of any disease, but is an external motivator. If a patient's disease allows him/her to miss work, avoid military duty, obtain financial compensation, obtain drugs, or avoid a jail sentence, these would be examples of a secondary gain. An example would be an individual having stomach cramps when household chores are completed by a family. In the context of a person with a significant mental or psychiatric disability, this effect is sometimes called secondary handicap.Tertiary morbid gain, a less well-studied process, is when a third party such as a relative or friend is motivated to gain sympathy or other benefits from the illness of the victim.Pseudohallucination
A pseudohallucination (from Ancient Greek: ψευδής (pseudḗs) "false, lying" + "hallucination") is an involuntary sensory experience vivid enough to be regarded as a hallucination, but considered by the person as subjective and unreal, unlike "true" hallucinations, which are considered real by patients with psychological disorders. Unlike normal hallucinations, which occurs when one sees, hears, smells, tastes or feels something that is not there, with a compelling feeling or thought that it is real, pseudohallucinations are recognised by the person as unreal. In other words, it is a hallucination that is recognized as a hallucination, as opposed to a "normal" hallucination which would be perceived as real.
The term 'pseudohallucination' appears to have been introduced by Friedrich Wilhelm Hagen. Hagen published his 1868 book "Zur Theorie der Halluzination," to define them as "illusions or sensory errors".The term 'pseudohallucination' was then further explored by the Russian psychiatrist Victor Kandinsky (1849–1889). In his work "On Pseudohallucinations" (Russian: "О псевдогаллюцинациях" [o psevdogalljucinacijah]), he described his psychotic experience defining pseudohallucinations as "subjective perceptions similar to hallucinations, with respect to its character and vividness, but that differ from those because these do not have objective reality".The term is not widely used in the psychiatric and medical fields, as it is considered ambiguous; the term nonpsychotic hallucination is preferred. Pseudohallucinations, then, are more likely to happen with a hallucinogenic drug. But "the current understanding of pseudohallucinations is mostly based on the work of Karl Jaspers".A further distinction is sometimes made between pseudohallucinations and parahallucinations, the latter being a result of damage to the peripheral nervous system.They are considered a possible symptom of conversion disorder in DSM-IV (2000). In DSM-5 (2013), this definition has been removed. Also, pseudohallucinations can occur in people with visual/hearing loss, with the typical such type being Charles Bonnet syndrome.Railway spine
Railway spine was a nineteenth-century diagnosis for the post-traumatic symptoms of passengers involved in railroad accidents.
The first full length medical study of the condition was John Eric Erichsen's classic book, On Railway and Other Injuries of the Nervous System. For this reason, railway spine is often known as Erichsen's disease.
Railway collisions were a frequent occurrence in the early 19th century. Exacerbating the problem was the fact that railway cars were flimsy, wooden structures with no protection for the occupants.
Soon a group of people started coming forward who claimed that they had been injured in train crashes, but had no obvious evidence of injury. The railroads rejected these claims as fake.
The nature of symptoms caused by "railway spine" was hotly debated in the late 19th century, notably at the meetings of the (Austrian) Imperial Society of Physicians in Vienna, 1886. Germany's leading neurologist, Hermann Oppenheim, claimed that all railway spine symptoms were due to physical damage to the spine or brain, whereas French and British scholars, notably Jean-Martin Charcot and Herbert Page, insisted that some symptoms could be caused by hysteria (now known as conversion disorder).Erichsen observed that those most likely to be injured in a railway crash were those sitting with their backs to the acceleration. This is the same injury mechanism found in whiplash. As with automobile accidents, railway and airplane accidents are now known to cause posttraumatic stress disorder (PTSD) and other psychosomatic symptoms in addition to physical trauma.Somatic symptom disorder
A somatic symptom disorder, formerly known as a somatoform disorder, is any mental disorder which manifests as physical symptoms that suggest illness or injury, but which cannot be explained fully by a general medical condition or by the direct effect of a substance, and are not attributable to another mental disorder (e.g., panic disorder). Somatic symptom disorders, as a group, are included in a number of diagnostic schemes of mental illness, including the Diagnostic and Statistical Manual of Mental Disorders. (Before DSM-5 this disorder was split into somatization disorder and undifferentiated somatoform disorder.)
In people who have been diagnosed with a somatic symptom disorder, medical test results are either normal or do not explain the person's symptoms, and history and physical examination do not indicate the presence of a known medical condition that could cause them, though the DSM-5 cautions that this alone is not sufficient for diagnosis. The patient must also be excessively worried about their symptoms, and this worry must be judged to be out of proportion to the severity of the physical complaints themselves. A diagnosis of somatic symptom disorder requires that the subject have recurring somatic complaints for at least six months.Symptoms are sometimes similar to those of other illnesses and may last for years. Usually, the symptoms begin appearing during adolescence, and patients are diagnosed before the age of 30 years. Symptoms may occur across cultures and gender. Other common symptoms include anxiety and depression. However, since anxiety and depression are also very common in persons with confirmed medical illnesses, it remains possible that such symptoms are a consequence of the physical impairment, rather than a cause. Somatic symptom disorders are not the result of conscious malingering (fabricating or exaggerating symptoms for secondary motives) or factitious disorders (deliberately producing, feigning, or exaggerating symptoms). Somatic symptom disorder is difficult to diagnose and treat. Some advocates of the diagnosis believe this is because proper diagnosis and treatment requires psychiatrists to work with neurologists on patients with this disorder.Temporary blindness
Temporary blindness, a type of non-permanent vision loss, may refer to:
Amaurosis fugax, or fleeting blindness
Conversion disorder, formerly called hysterical blindness
Flash blindness, caused by exposure to high-intensity light.