The Skeptics Society & Skeptic magazine

Penis Panics:
The Psychology of Penis Shrinking
Mass Hysterias

by Robert E. Bartholomew

It sounds like something from a poor B movie. It might even make the 1978 cult film Attack of the Killer Tomatoes seem plausible. I’m referring to scares where communities are swept up in the fear that their sex organs are rapidly shrinking. In parts of Asia and the Orient entire regions are occasionally overwhelmed by terror-stricken men who believe that their penises are shriveling up or retracting into their bodies. Those affected often take extreme measures and place clamps or string onto the precious organ or have family members hold the penis in relays until an appropriate treatment is obtained, often from native healers. Occasionally women are affected, believing their breasts or vaginas are being sucked into their bodies. Episodes can endure for weeks or months and affect thousands. Psychiatrists are divided as to the cause of these imaginary scares. Some believe that it is a form of group psychosis triggered by stress, while others view it as mass hysteria. How can groups of people come to believe that their sex organs are shrinking? We will try to unravel this mystery by briefly describing several genital-shrinking scares, their similarities, and the factors involved in triggering them.

While genitalia-shrinking is known by a variety of names in different cultures, psychiatrists refer to it with the generic term “koro.” A Malay word of uncertain derivation, koro may have arisen from the Malay word “keruk,” meaning to shrink (Gwee, 1968, 3), although it is more likely a reflection of the Malaysian-Indonesian words for “tortoise” (kura, kura-kura, and kuro). In these countries, the penis, especially the glans or tip, is commonly referred to as a tortoise head. This led Dutch scientist P.M. Van Wulfften-Palthe to conclude that this is how the modern term “koro” most likely got its name: “The fact that a tortoise can withdraw its head with its wrinkled neck under its shell literally into its body, suggested…the mechanism…in ‘koro’ (‘kura’) and gave it its name” (1936, 536).

The Anatomy of a Mass Hysteria

The first well-documented outbreak in modern times occurred in October and November, 1967, when hospitals on the tiny Southeast Asian island nation of Singapore were inundated by frantic citizens who were convinced that their penises were shrinking and would eventually disappear, at which time, many believed, death would result. “Victims” used everything from rubber bands to clothes pins in desperate efforts to prevent further perceived retraction. These methods occasionally resulted in severe organ damage and some pretty sore penises. At the height of the scare the Singapore Hospital treated about 75 cases in a single day. The episode occurred amid rumors that eating pork vaccinated for swine fever prior to slaughter could trigger genitalia shrinkage. One erroneous report even claimed that a pig dropped dead immediately after inoculation when its penis suddenly retracted!

The panic abruptly ended when the Singapore Medical Association and Health Ministry held public news conferences to dispel fears. Writing in the prestigious British Journal of Psychiatry, Singaporian doctor C.T. Mun described two typical cases. In one, a pale 16 year-old boy rushed into the clinic accompanied by his parents and clutching his penis. After providing reassurance and a sedative, there was no recurrence. The frightened boy said that he had heard the rumors of contaminated pork at school, had eaten pork that morning, and upon urinating, his penis appeared to have shrunk. At that point he hung on for all he was worth and shouted for help. In a second case, a mother dashed into the clinic clutching the penis of her 4-month-old baby frantically seeking help. Dr. Mun said that “The child had not been well for two days with cold and a little diarrhoea. The mother was changing his napkin…when the child had colic and screamed. The mother saw the penis getting smaller and the child screamed and [she] thought he had koro. She had previously heard the rumors. The mother was first reassured, and the baby’s cold and diarrhoea treated. The child was all right after that.”

Most Singaporeans are of Chinese origin where there is a common belief in the reality of shrinking genitalia. Chinese medical texts from the 19th century even describe such cases as caused by an actual disease. Pao Sian-Ow’s book, New Collection of Remedies of Value published in 1834, states that episodes occur when “the penis retracts into the abdomen. If treatment is not instituted at once and effective, the case [patient] will die. The disease is due to the invasion of cold vapors and the treatment is to employ the ‘heaty’ drugs.”

At least 5,000 inhabitants in a remote area of southern Guangdong province, China, were affected by a genital-shrinking panic between August 1984 and the summer of 1985 (Jilek, 1986, 273). Male residents of the region are reared to practice restraint in matters of sexual desire and activity, as excessive semen discharge is believed to cause poor physical and mental health, even death. If that wasn’t enough to worry about, many residents believe that certain spirits of the dead, especially female fox maidens, wander in search of penises that will give them powers. Each of the 232 “victims” surveyed by University of Hawaii psychiatrist Wen-Shing Tseng and his colleagues, was convinced that an evil female fox spirit was the culprit, while 76 percent of those affected had witnessed others being “rescued.” Most of these cases occurred at night following a chilly sensation which would appear before a feeling of penile shrinkage. Tseng and his researchers reported: “Thinking this [chill] to be a fatal sign and believing that they were affected by an evil ghost, they [koro “victims”] became panic stricken and tried to pull at their penises, while, at the same time, shouting for help” (Tseng et al., 1988, 1540). Interestingly, several children reported shrinkage of their tongue, nose and ears, reflecting the prevalent ancient Chinese belief that any male (yang) organs can shrink or retract. Tseng investigated a separate episode in 1987, affecting at least 300 residents on the Leizhou Peninsula of Guangdong province. Genital-shrinking panic is well-known in southern China, with episodes recorded in 1865, 1948, 1955, 1966, and 1974, all involving at least several hundred residents (Bartholomew, 1998).

Dr. Tseng has sought to determine why episodes repeatedly occur in the vicinity of Leizhou Peninsula and Hainan Island, but never spread to the principal section of Guangdong province or other parts of China, and why it is that only certain residents in a region report koro, while others do not. It was found that those affected held the more intense koro-related folk beliefs relative to a control group from the adjacent nonaffected area (Tseng et al. 1992, 122), helping to explain “why each time the koro epidemic spread from the Peninsula, it would cease when it reached the urban area of Guangzhou, where the people are more educated and hold less belief in koro.” While recognizing the importance of rumors and traditional beliefs in precipitating episodes, Tseng considers koro outbreaks in southern China to be a psychiatric disorder (“genital retraction panic disorder”) which primarily affects susceptible individuals, such as the poorly educated and those possessing below normal intellectual endowment who are experiencing social crisis or tension (1988, 1542; 1992, 117).

Another koro episode happened in northeast Thailand between November and December, 1976, affecting about 2,000 people, primarily rural Thai residents in the border provinces of Maha Sarakham, Nakhon Phanom, Nong Khai, and Udon Thani. Symptoms included the perception of genitalia shrinkage and impotence among males, while females typically reported sexual frigidity, with breast and vulva shrinkage. Other symptoms were panic, anxiety, dizziness, diarrhea, discomfort during urination, nausea, headaches, facial numbness, and abdominal pain. Some patients temporarily lost consciousness, and many were fearful of imminent death. Of 350 subjects studied in detail, irrespective of whether they sought treatment from native healers or physicians, “most patients had recovered within one day and all within one week” (Suwanlert and Coates, 1979, 65).

The episode began at a technical college in Udon Thani province, with rumors that Vietnamese immigrants had deliberately contaminated food and cigarettes with a koro-inducing powder. During this period, there was a strong anti-Vietnamese sentiment throughout Thailand following communist victories in Southeast Asia in 1975, the growing influence of the Communist Party of Thailand, and the perceived control of Cambodia and Laos by the Vietnamese. Anti-Vietnamese sentiments in the region were especially strong in the month before the episode (Andelman, 1976a, 1976b), with allegations by Thailand’s Interior Minister that there was “solid evidence” of a plot whereby “Vietnamese refugees would incite rioting in northeast Thailand, providing Vietnam with an excuse to invade” on February 15 (Andelman, 1976c). As the episode continued, the poisoning rumors became self-fulfilling as numerous Thai citizens recalled that previously consumed food and cigarettes recently purchased from Vietnamese establishments had an unusual smell and taste. However, an analysis of suspected sources by the Government Medical Science Department “detected no foreign substance that could possibly cause sexual impotence or contraction of the male sex organ” (Jilek and Jilek Aall, 1977a, 58).

Koro rumors, combined with pre-existing awareness of the “disease,” served to foster and legitimate its plausible existence. Suwanlert and Coats (1979, 65) found that 94 percent of “victims” studied “were convinced that they had been poisoned.” Negative government analysis of alleged tainted substances was undermined by contradictory statements issued by authority figures in the press. Security officials attributed the tainting substances believed responsible for causing the koro in food to a mixture of vegetable sources undetectable by medical devices (1977a, 58).

Another outbreak occurred in northeastern India from July to September, 1982. Cases numbered in the thousands, as many males believed their penises and testicles were retracting while women felt their breasts “going in.” Indian psychiatrist Ajita Chakraborty said the panic reached such proportions that medical personnel toured the region, reassuring those affected with loud speakers (Chakraborty et al., 1983). Some parents tied string to their sons’ penises to reduce or stop retraction, a practice that occasionally produced penile ulcers. Authorities even went to the extent of measuring penises at intervals to allay fears. A popular local remedy was to have the “victim” tightly grasp the affected body part, drink lime juice and be dowsed with buckets of cold water, (Sachdev and Shukla, 1982, 1161). While there was evidence of pre-existing kororelated beliefs among some residents, the episode spread across various religious and ethnic groups, social castes, and geographical areas by way of rumors. Based on interviews with 30 “victims,” investigating physicians were unable to identify obvious signs of psychological disturbance (Sachdev and Shukla, 1982).

Magical Genitalia Loss in Nigeria

If koro panics now top your ranking of the most bizarre human delusions, you may have to rejuggle your list. For in parts of Africa, there is an even stranger belief—vanishing genitalia! “Magical” genitalia loss in Nigeria has also been interpreted as an exotic, unambiguous example of isolated individual mental disturbance. The influence of socio-cultural context is evident in collective episodes of magical genitalia loss in Nigeria reported over the past 20 years. Psychiatrist Sunny Ilechukwu (1988) writes in the Transcultural Psychiatric Research Review that while working at a teaching hospital in Kaduna, northern Nigeria in 1975, he was approached by a police officer who was accompanied by two men. One of the men made the startling claim that the other had caused his penis to vanish; the officer, acting on orders from his superior, was to obtain a medical report to settle the dispute. The patient explained that he was walking along a street and “felt his penis go” after the robes worn by the other man had touched him. Incredulous, Ilechukwu initially refused to handle the case, but later agreed to conduct a physical exam, which transpired in full view of the concerned parties. The patient stood and stared straight ahead until it was announced that his genitals were normal. Reacting in disbelief, the patient glanced down at his genitals and suggested that they had just reappeared! The policeman then indicated that charges would be filed against the man for falsely reporting an incident.

This case may appear to be a clear case of isolated individual mental disturbance, as it is beyond Western credulity that people could believe that entire body parts were missing when clearly they were not. Yet, Ilechukwu reports on “epidemics” of temporary magical penis loss in Nigeria during the mid-1970s, and again in 1990. A major Nigerian episode of “vanishing” genitalia in 1990, mainly affected men, but sometimes women, while walking in public places. Accusations were typically triggered by incidental body contact with a stranger that was interpreted as intentionally contrived, followed by unusual sensations within the scrotum. The affected person would then physically grab their genitals to confirm that all or parts were missing, after which he would shout a phrase such as “Thief! my genitals are gone!” (Ilechukwu, 1992, 95). The “victim” would then completely disrobe to convince quickly gathering crowds of bystanders that his penis was actually missing. The accused was threatened and usually beaten (sometimes fatally) until the genitals were “returned.” While some “victims” soon realized that their genitalia were intact, “many then claimed that they were ‘returned’ at the time they raised the alarm or that, although the penis had been ‘returned,’ it was shrunken and so probably a ‘wrong’ one or just the ghost of a penis” (95). In such instances, the assault or lynching would usually continue until the “original, real” penis reappeared.

Ilechukwu reports that incidents quickly spread like wildfire across the country. “Men could be seen in the streets of Lagos holding on to their genitalia either openly or discreetly with their hands in their pockets. Women were also seen holding on to their breasts directly or discreetly by crossing the hands across the chest. It was thought that inattention and a weak will facilitated the ‘taking’ of the penis or breasts. Vigilance and anticipatory aggression were thought to be good prophylaxis.”

The role of socio-cultural traditions in triggering episodes is evident as many Nigerian ethnic groups “ascribe high potency to the external genitalia as ritual and magical objects to promote fecundity or material prosperity to the unscrupulous. Ritually murdered persons are often said to have these parts missing” (Ilechukwu, 1988, 313). The belief in the reality of vanishing genitalia is institutionalized to such an extent that during the 1990 episode, several influential Nigerians, including a court judge, protested vehemently when police released suspected genital thieves, and many knowledgeable citizens “claimed that there was a real—even if magical—basis for the incidents” (Ilechukwu, 1992, 96–97). One Christian priest supported cultural beliefs in genital theft by citing a biblical passage where Christ asked “Who touched me?” because the “power had gone out of him,” claiming that it was a reference to genital stealing (101–102). Ilechukwu concludes that socio-cultural beliefs related to magical genitalia loss in Nigeria render sexually maladjusted individuals susceptible to “attacks.”

Unravelling the Mystery

There have been a few sporadic reports of individual penis-shrinking occurring in widely separated cultural settings, but there is little doubt that most of these people are seriously disturbed. Common themes include preoccupations with masturbation and nocturnal emissions, perceived sexual inadequacies or excesses, and ignorance, inexperience or insufficient confidence in sexual relationships. These factors may be reinforced by social and cultural beliefs about sexuality. Unlike “epidemics,” individual cases can persist for months or years in people with obvious psycho-sexual problems and psychiatric disturbance. For instance, Emsley (1985) describes the case of a man who became mentally traumatized and developed a great fear of impotence after being unwillingly circumcised in a tribal ritual. He then failed to get an erection while trying to have sex—at which point he could feel his penis shrinking. Many disturbed men who believe their penis is shrinking suffer from schizophrenia, where over-valued notions or delusions regarding damaged or impaired sexual organs can occur (Gittelson and Levine, 1966; Edwards, 1970; and Devan and Hong, 1987). In one case recorded by psychiatrists Edward Kendall and Peter Jenkins (1987) while working in a Columbia, SC, hospital, a 35 year-old schizophrenic man was hospitalized after experiencing delusions of having “the largest penis in the world.” A few days later, he tied cloth around his penis to prevent retraction, believing he was changing into a woman!

Large-scale genitalia-shrinking episodes are typified by the symptoms of anxiety persisting for a few minutes to several days and those affected always experience a complete “recovery” upon being convinced they are no longer in danger. Isolated singular cases experience more severe symptoms and may never recover. For instance, British psychiatrist Anne Cremona (1981), treated a man who at age 18 was unable to get an erection on three different occasions while attempting intercourse. He came to believe that his penis was abnormal and experienced great anxiety, violence, drug abuse, began hearing voices (schizophrenia), and became a hypochondriac. At age 21 in 1977, while walking down the street, he suddenly felt his penis shrink half an inch, and after two years of such delusions, Dr. Cremona reported that his koro symptoms were “as frequent and distressing as ever” and were unresponsive to drug treatment. In another case, an Englishman with koro was afraid to urinate in public, fearing that friends might spot him being “unable to find his penis when using a urinal,” and tease him. His symptoms persisted for 20 years but disappeared after he received psychotherapy and drugs (Berrios and Morley 1984). With cases like these on record, it’s no wonder that some psychiatrists have assumed that epidemic koro is also triggered by similar psychological disturbances. Yet, a closer look at mass outbreaks reveals that they result from an entirely different process (Bartholomew, 1984, 1998).

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The few isolated, individual cases often take years to recover, and do so only after the underlying sexual problems are addressed. Drug treatment can also sometimes be helpful. “Victims” of genitalia-shrinking panics recover within hours or days after being convinced that the “illness” is over or never existed, and most clearly lack any psycho-sexual problems. Episodes also share similar symptoms: anxiety, sweating, nausea, headache, transient pain, pale skin, palpitations, blurred vision, faintness, insomnia, and a false belief that body parts are shrinking. These symptoms are normal body responses to extreme fear. The penis, scrotum, breasts, and nipples are the most physiologically plastic external body parts, regularly changing size and shape in response to various stimuli from sexual arousal to temperature changes. Studies also reveal that stress, depression, illness, and urination can cause small but discernible penis shrinkage (Oyebode et al., 1986; Thase et al., 1988). Another key factor is the nature of human perception, which is notoriously unreliable (Ross et al., 1994). Perception is also preconditioned by a person’s mental outlook and social and cultural reference system. In each of the countries reporting epidemic koro, there were pre-existing beliefs that genitalia could shrivel up under certain circumstances.

Far from exemplifying group psychosis, disorder or irrationality, penis-shrinking panics are a timely reminder that no one is immune from mass delusions, and that the influence of culture and society on individual behavior is far greater than most of us would like to admit. This is a valuable lesson to remember at the dawn of a new millennium. It is all too easy to think of past or non-Western delusions with a wry smile as if we are somehow now immune or those involved were naive and gullible. Yet, the main reason for the absence of penis-shrinking epidemics in Western societies is their incredible nature. It is simply too fantastic to believe. But any delusion is possible if the false belief underlying it is plausible. So while we may laugh at the poor “misguided” Indian or Chinese for believing in penis and breast-shrinking panics, we are haunted by our own unique delusions of crashed saucers, alien abductors, and CIA cover-ups of just about everything.