11. Prosopagnosia: the inability to recognize faces.
When a person suffers from prosopagnosia, their ability to recognize faces becomes impaired. The rest of their brain functions normally. Prosopagnosia occurs after acute brain damage or can be the result of a birth defect. An estimated 2.5% of the world’s population suffers from this medical condition.
Several attempts at remediation using therapies have not resulted in any lasting improvement on prosopagnosia patients. (source)
12. Auto-brewery syndrome: getting drunk eating any food.
A man named Nick Hess wakes up every day feeling drunk and vomiting. This unusual medical condition occurs when the stomach and intestines experience an overgrowth of yeast and turn the carbohydrates present in any food consumed into alcohol. The alcohol then spreads into the blood system making the patient experience dizziness, exhaustion and nausea. Hess was suffering from ‘auto-brewery syndrome’. (source)
13. Capgras delusion: false belief in identical-looking impostors.
This condition is a delusion where the patient believes that a loved one, be it a friend, parent, spouse or any close family member, has been replaced by an identical-looking impostor.
Capgras delusion is usually seen in people suffering from paranoid schizophrenia or dementia and can be caused by other kinds of brain injuries. It occurs more frequently among women and is often associated with migraine attacks and diabetes.
Individual therapy is the best way to deal with capgras delusion. (source)
14. Post-orgasmic illness syndrome: allergic to one’s own semen.
Some men are known to experience flu-like symptoms such as a runy nose, fever, severe exhaustion, or itching of eyes, immediately after ejaculation. They are suffering from “post-orgasmic illness syndrome” which takes up to three years to cure by undergoing hyposensitization therapy. In this therapy, the patients are injected with a solution containing a high concentration of their own semen over the course of a long period. (source)
15. Cotard delusion: A mental illness where you are completely sure that you are dead.
In this delusion, the patients are totally convinced that they are dead, literally or figuratively. A statistical analysis based on a hundred people who believe that they are walking corpses showed that 69% of the patients were living in denial of their own existence amid feelings of depression and self-loathing.
Once there was a women known as “Mademoiselle X” who was utterly convinced that she deserved to die an unnatural death. Eventually, she starved herself to death. (source)