Posted in Psychology & Medicine

Laughter Epidemic

It is said that laughter is infectious. In 1962, an extreme case of “laughter infection” happened in village in Tanzania. The phenomenon originated in a boarding school for girls. On January 30, three girls spontaneously burst out in laughter and could not stop themselves from laughing. Soon after, the whole class was suffering from fits of uncontrollable laughter. The “infection” then spread throughout the school, claiming 95 of the 159 students over a stretch of two months. This strange symptom of uncontrollable laughter lasted anywhere from a few hours to 16 days. Interestingly, teachers were not affected and only girls between the ages of 12 to 18 were affected. By March 18, the school was forced to close down due to students not being able to focus during class.

The laughter epidemic was not localised to the school. After the school shut down and the girls returned home, fellow villagers were afflicted by the laughing disease, resulting in 217 villagers being “infected” by May (mostly children and teenagers). By June, the laughing epidemic spread to another nearby school, affecting 48 girls. The epidemic then went on to claim two more schools, forcing them to close down. By the time the epidemic died down (6 to 18 months after “patient zero”), it had affected over a 1000 people and shut down 14 schools.

So what was this strange disease? Was it some new viral infection causing neurological symptoms? Was it a toxin in the water supply? The answer was even simpler: mass psychogenic illness, also known as mass hysteria. Mass hysteria is a psychological phenomenon that occurs in groups placed in high-tension situations, such as within an airplane. This setting is perfect for triggering a mass delusion, causing the person to believe they are suffering from a physical disease. The trigger is usually another “patient” and the hysteria spreads like wildfire, usually by people seeing affected victims. Although the above case makes mass hysteria look like a harmless, amusing phenomenon, psychosomatism (when the mind tricks the body into thinking it is sick) can cause symptoms such rashes, fevers, vomiting and even paralysis. In fact, all of these symptoms were also reported during the Tanganyika laughter epidemic.

Posted in Psychology & Medicine

Symptom Reporting

Some people always complain of symptoms, claiming that they are sick, while some people never seem to complain even if they have a whole list of symptoms. Why is there a difference in symptom reporting between people? For example, women are more likely to recognise symptoms and report them compared to men. This is because men are generally under the social pressure of needing to appear strong and healthy, so they become stoic and less sensitive to pain and disease. Women are usually more sensitive to internal bodily changes and worry more about their health.

According to a psychological theory called the competition for cues hypothesis, there are two signals that compete for attention when we recognise symptoms. The first is bodily changes, i.e. internal cues, while the other is external stimuli from what happens around us. Awareness of symptoms follows a ratio between these two signals: if there is a strong internal cue such as severe pain, we notice symptoms more quickly, while if there are many distractions, we may not notice the symptom. For example, according to a study people can run faster when listening to music and running through a forest with plenty to see. This is because music and the scenery distract the runner from internal cues. As we can only process a certain amount of information at a given moment, the more distractions there are the less sensitive we become to signals from inside our body.

Another factor that affects symptom reporting is illness labelling. The more information we have about a disease, the more we search for those symptoms. For example, if you yawn or scratch yourself, people around you will do the same. This is because they see you yawning and subconsciously believe that they should yawn too. This can be a powerful effect, as seen in mass hysteria. This strange phenomenon occurs when a person observes a sick person and their brain believes they are sick too, beginning to show symptoms despite being healthy. A similar example is seen in medical student disease, where medical students, with their extensive knowledge of diseases, match their own symptoms to symptom lists of rare diseases. For example, they might think that their high blood pressure is due to a phaeochromocytoma or renal artery stenosis, rather than just hypertension.

However, the opposite can occur where people fail to notice important symptoms and suffer serious consequences as a result. For instance, not all cases of heart attacks (myocardial infarction) cause unconsciousness and a patient may believe they are fine when only chest pain occurs. Failure to get treated as soon as possible at a hospital may result in ventricular fibrillation, leading to sudden death.

Posted in Psychology & Medicine

Hysteria

Hysteria is a disease that was believed until the late 19th century to be a disease unique to women due to a pathology of the uterus (hystera is Greek for uterus). The most common symptom was mental disturbance (such as extreme moods) accompanied by shortness of breath, vaginal dryness, nervousness, insomnia, oedema, faintness and many more. The treatment back then was for a physician to massage or stimulate the patient’s vagina to induce an orgasm. By the 19th century, the treatment evolved and involved vibrators and water massage machines.

This disease was first noted by Hippocrates, the father of modern medicine. Galen, another famous physician in the 2nd century, believed it to be caused by sexual deprivation. Thus, sexual intercourse was prescribed as treatment in the Middle Ages.

Modern medicine no longer recognises hysteria as a medical condition and is now referred to as sexual dysfunction (the sexual treatments described above are no longer used either). However, there is a condition called mass hysteria that indeed exists.
This is a psychological phenomenon rather than a disease, commonly occurring in closed spaces such as planes or in crowds in a state of panic. When a high tension situation arises, people easily become delusional and believe that they are suffering from a disease. The body reacts to this with actual symptoms such as a psychosomatic rash. These symptoms can be as severe as fevers, vomiting and even paralysis.

If many people are all complaining of similar symptoms and infectious disease seems unlikely, there is an easy way of diagnosing mass hysteria. Tell the patients that they have a rare disease and begin listing the symptoms they complain of. At the end, make up a false symptom (e.g. “shaking of the left hand”). If the patients all suddenly start to shake their left hands (which causes them to panic more), it is likely that their panicking brain is causing the symptoms rather than some pathogen. Symptoms subside after the patients relax.

Interestingly, mass hysteria affects women much more than men.