With appliances like used lingerie vending machines and attractions like “Love Hotels,” it’s clear some Japanese don’t regard unconventional sexuality as very taboo as the rest of the world. Not only is there a subculture in Japan embracing all things sexually taboo, apparently they research it. A recent study from the island nation used MRI scans to find exactly what was causing a man's underwear fetish. The conclusion? Decreased blood flow to the brain.

The test subject of the Japanese study is arguably more interesting than the actual results. According to Discover Magazine, the 24-year-old patient was referred to the hospital after being caught once again stealing women’s underwear. “The patient had stolen women’s underwear on multiple occasions since the age of 11 years, although he showed no interest in underwear that belonged to his mother, sister, and girlfriend's,” explained lead researcher Koji Masuda and their colleagues.

The researchers used a Single Photon Emission Computed Tomography (SPECT) scan of the patient’s brain to see if there was a biological explanation for his abnormal obsession. The scan revealed that he did, in fact, have a slightly less than normal brain layout. The cerebral blood flow was decreased in the temporal and occipital lobes.

However, as pointed out by Discover, this decrease in blood flow may or may not have anything to do with the patient's extracurricular activities. Still, the researchers went on to “diagnose” the patient with fetishism, based on a combination of his history and the brain scan’s results. According to the report, he went on to be “successfully treated with behavioral therapy.”

As noted by Discover, this particular study lacked multiple comparisons in their statistical testing, which greatly comprised the accuracy of their results. The findings, although interesting, explain a correlation between brain flow and fetishes, rather than causation. Further research is required before any definitive results may be concluded.

Fetishism is characterized as a disorder when there is a pathological assignment of sexual fixation, fantasies, or behaviors toward an inanimate object. As explained by Psychology Today, the object of affection is commonly an item of clothing, such as a high-heeled shoe, or in this case, female underwear.

As for explaining the cause of fetishes, most experts agree that they begin early in life due to an incident, not a biological oddity. Fetishes can be a hindrance, such as in the case of this young Japanese man constantly getting arrested, or in relationships where one partner finds themselves incompatible with the other’s fetish. For the most part, though, they are regarded as harmless and not considered as a condition warranting treatment.

Source: Masuda K, Ishitobi Y, Tanaka Y, Akiyoshi J. Underwear fetishism induced by bilaterally decreased cerebral blood flow in the temperoccipital lobe. BMJ Case Reports. 2014.