mass psychogenic illness mass psychogenic illness mass psychogenic illness (mpi), also called mass sociogenic illness, mass psychogenic disorder, epidemic hysteria, involves the spread of illness symptoms through a population where there is no infectious agent responsible for contagion. it 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 causes that are known. mass psychogenic illnessother namesmass hysteria, epidemic hysteria, mass sociogenic illness, mass psychogenic disorderdancing plagues of the middle ages are thought to have been caused by mass hysteria.specialtypsychiatry, clinical psychologysymptomsheadache, dizziness, nausea, abdominal pain, cough, fatigue, sore throatrisk factorschildhood or adolescence, intense media coveragedifferential diagnosisactual diseases, mass delusions, somatic symptom disorder causes mpi is distinct from other types of collective delusions by involving physical symptoms. it is not well understood and its causes are uncertain. qualities of mpi outbreaks often include: symptoms that have no plausible organic basis; symptoms that are transient and benign; symptoms with rapid onset and recovery; occurrence in a segregated group; the presence of extraordinary anxiety; symptoms that are spread via sight, sound or oral communication; a spread that moves down the age scale, beginning with older or higher-status people; a preponderance of female participants. british psychiatrist simon wessely distinguishes between two forms of mpi: mass anxiety hysteria "consists of episodes of acute anxiety, occurring mainly in schoolchildren. prior tension is absent and the rapid spread is by visual contact." mass motor hysteria "consists of abnormalities in motor behaviour. it occurs in any age group and prior tension is present. initial cases can be identified and the spread is gradual. ... he outbreak may be prolonged." while his definition is sometimes adhered to, others such as ali-gombe et al. of the university of maiduguri, nigeria contest wessely's definition and describe outbreaks with qualities of both mass motor hysteria and mass anxiety hysteria. the dsm-iv-tr does not have specific diagnosis for this condition but the text describing conversion disorder states that "in 'epidemic hysteria', shared symptoms develop in a circumscribed group of people following 'exposure' to a common precipitant." common symptoms timothy f. jones of the tennessee department of health compiles the following symptoms based on their commonality in outbreaks occurring in 1980–1990: symptom percent reporting headache 67 dizziness or light-headedness 46 nausea 41 abdominal cramps or pain 39 cough 31 fatigue, drowsiness or weakness 31 sore or burning throat 30 hyperventilation or difficulty breathing 19 watery or irritated eyes 13 chest tightness/chest pain 12 inability to concentrate/trouble thinking 11 vomiting 10 tingling, numbness or paralysis 10 anxiety or nervousness 8 diarrhea 7 trouble with vision 7 rash 4 loss of consciousness/syncope 4 itching 3 prevalence and intensity adolescents and children are frequently affected in cases of mpi. the hypothesis that those prone to extraversion or neuroticism, or those with low iq scores, are more likely to be affected in an outbreak of hysterical epidemic has not been consistently supported by research. bartholomew and wessely state that it "seems clear that there is no particular predisposition to mass sociogenic illness and it is a behavioural reaction that anyone can show in the right circumstances." intense media coverage seems to exacerbate outbreaks. the illness may also recur after the initial outbreak. john waller advises that once it is determined that the illness is psychogenic, it should not be given credence by authorities. for example, in the singapore factory case study, calling in a medicine man to perform an exorcism seemed to perpetuate the outbreak. research besides the difficulties common to all research involving the social sciences, including a lack of opportunity for controlled experiments, mass sociogenic illness presents special difficulties to researchers in this field. balaratnasingam and janca report that the methods for "diagnosis of mass hysteria remain contentious." according to jones, the effects resulting from mpi "can be difficult to differentiate from bioterrorism, rapidly spreading infection or acute toxic exposure." these troubles result from the residual diagnosis of mpi. there is a lack of logic in an argument that proceeds: "there isn't anything, so it must be mpi." it is an example of an argument from ignorance, with ignorance here intended to mean "an absence of contrary evidence". it precludes the notion that an organic factor could have been overlooked (i.e. that there may have been insufficient investigation), or the possibility that the answer may currently be unknown but known at a future point in time. nevertheless, running an extensive number of tests extends the probability of false positives. singer, of the uniformed schools of medicine, has summarized the problems with such a diagnosis: ou find a group of people getting sick, you investigate, you measure everything you can measure ... and when you still can't find any physical reason, you say "well, there's nothing else here, so let's call it a case of mpi." relationship to autism and mirror neurons due to the role of the visual and auditory systems in mpi, a link between mpi and mirror neurons has been suggested. in this context, mpi appears as the neurological opposite of autism, caused by an overactive, not underactive, mirror neuron system. this could in turn explain the gender difference bias observed in these two conditions, with autism predominantly affecting males (persons with autism show diminished activity in the mirror neuron system), and mpi predominantly affecting young girls, which appear have a more sensitive mirror system. in history middle ages the earliest studied cases linked with epidemic hysteria are the dancing manias of the middle ages, including st. john's dance and tarantism. these were supposed to be associated with spirit possession or the bite of the tarantula. those with dancing mania would dance in large groups, sometimes for weeks at a time. the dancing was sometimes accompanied by stripping, howling, the making of obscene gestures, or even (reportedly) laughing or crying to the point of death. dancing mania was widespread over europe. between the 15th and 19th centuries, instances of motor hysteria were common in nunneries. the young ladies that made up these convents were sometimes forced there by family. once accepted, they took vows of chastity and poverty. their lives were highly regimented and often marked by strict disciplinary action. the nuns would exhibit a variety of behaviors, usually attributed to demonic possession. they would often use crude language and exhibit suggestive behaviors. one convent's nuns would regularly meow like cats. priests were often called in to exorcise demons. in factories mpi outbreaks occurred in factories following the industrial revolution in england, france, germany, italy and russia as well as the united states and singapore. w. h. phoon, ministry of labour in singapore, gives a case study of six outbreaks of mpi in singapore factories between 1973 and 1978. they were characterized by (1) hysterical seizures of screaming and general violence, wherein tranquilizers were ineffective (2) trance states, where a worker would claim to be speaking under the influence of a spirit or jinn and (3) frightened spells: some workers complained of unprecedented fear, or of being cold, numb, or dizzy. outbreaks would subside in about a week. often a bomoh (medicine man) would be called in to do a ritual exorcism. this technique was not effective and sometimes seemed to exacerbate the mpi outbreak. females and malay people were affected disproportionately. especially notable is the "june bug" outbreak: in june 1962, a peak month in factory production, 62 workers at a dressmaking factory in a textile town in the southern united states experienced symptoms including severe nausea and breaking out on the skin. most outbreaks occurred during the first shift, where four fifths of the workers were female. of 62 total outbreaks, 59 were women, some of whom believed they were bitten by bugs from a fabric shipment, so entomologists and others were called in to discover the pathogen, but none was found. kerchoff coordinated the interview of affected and unaffected workers at the factory and summarizes his findings: strain – those affected were more likely to work overtime frequently and provide the majority of the family income. many were married with children. affected persons tended to deny their difficulties. kerchoff postulates that such were "less likely to cope successfully under conditions of strain." results seemed consistent with a model of social contagion. groups of affected persons tended to have strong social ties. kerchoff also links the rapid rate of contagion with the apparent reasonableness of the bug infestation theory and the credence given to it in accompanying news stories. stahl and lebedun describe an outbreak of mass sociogenic illness in the data center of a university town in the united states midwest in 1974. ten of 39 workers smelling an unconfirmed "mystery gas" were rushed to a hospital with symptoms of dizziness, fainting, nausea and vomiting. they report that most workers were young women either putting their husbands through school or supplementing the family income. those affected were found to have high levels of job dissatisfaction. those with strong social ties tended to have similar reactions to the supposed gas, which only one unaffected woman reported smelling. no gas was detected in subsequent tests of the data center. in schools mass hysteria affected schools in berry, alabama, and miami beach in 1974, with the former episode taking the form of recurring pruritus, and the latter initially triggering fears of poison gas (it was traced back to a popular student who happened to be sick with a virus). thousands were affected by the spread of a supposed illness in a province of kosovo in march to june 1990, exclusively affecting ethnic albanians, most of whom were young adolescents. a wide variety of symptoms were manifested, including headache, dizziness, impeded respiration, weakness/adynamia, burning sensations, cramps, retrosternal/chest pain, dry mouth and nausea. after the illness had subsided, a bipartisan federal commission released a document, offering the explanation of psychogenic illness. radovanovic of the department of community medicine and behavioural sciences faculty of medicine in safat, kuwait, reports: this document did not satisfy either of the two ethnic groups. many albanian doctors believed that what they had witnessed was an unusual epidemic of poisoning. the majority of their serbian colleagues also ignored any explanation in terms of psychopathology. they suggested that the incident was faked with the intention of showing serbs in a bad light but that it failed due to poor organization. rodovanovic expects that this reported instance of mass sociogenic illness was precipitated by the demonstrated volatile and culturally tense situation in the province. the tanganyika laughter epidemic of 1962 was an outbreak of laughing attacks rumored to have occurred in or near the village of kanshasa on the western coast of lake victoria in the modern nation of tanzania, eventually affecting 14 different schools and over 1,000 people. on the morning of thursday 7 october 1965, at a girls' school in blackburn in england, several girls complained of dizziness. some fainted. within a couple of hours, 85 girls from the school were rushed by ambulance to a nearby hospital after fainting. symptoms included swooning, moaning, chattering of teeth, hyperpnea, and tetany. moss and mcevedy published their analysis of the event about one year later. their conclusions follow. their conclusion about the above-average extraversion and neuroticism of those affected is not necessarily typical of mpi: clinical and laboratory findings were essentially negative. investigations by the public health authorities did not uncover any evidence of pollution of food or air. the epidemiology of the outbreak was investigated by means of questionnaires administered to the whole school population. it was established that the outbreaks began among the 14-year-olds, but that the heaviest incidence moved to the youngest age groups. by using the eysenck personality inventory, it was established that, in all age groups, the mean e and n scores of the affected were higher than those of the unaffected. the younger girls proved more susceptible, but disturbance was more severe and lasted longer in the older girls. it was considered that the epidemic was hysterical, that a previous polio epidemic had rendered the population emotionally vulnerable, and that a three-hour parade, producing 20 faints on the day before the first outbreak, had been the specific trigger. the data collected were thought to be incompatible