The tongue can perceive five tastes—sour, sweet, bitter, salty, and umami.

Experiencing these sensations occurs because receptors on the surface of taste bud cells are activated by food, triggering the nerve fibers to transmit signals to the brain, letting you know whether it's tasty barbecue or fresh strawberries.

However, the function of your tongue extends beyond this. The tongue is sensitive to temperature, pressure, and chemicals, giving rise to these peculiar sensations known as chemosensory perceptions. One of the most intriguing examples is pepper. When you eat it, your mouth starts to tingle, followed by a strange numbing sensation. This is caused by a substance called hydroxy-alpha sanshool. This compound attaches to the cell membranes of tongue neurons, producing this peculiar sensation.

In fact, in a 2013 paper, researchers applied this substance to volunteers' lips and asked them to indicate which frequency resembled the sensation caused by pepper. The unanimous answer was around 50 Hertz, suggesting a specific nerve is associated with this feeling and is highly sensitive to a particular frequency. Another substance that can temporarily alter your sense of taste is capsaicin, found in the chili pepper. Capsaicin attaches to receptors responsible for detecting temperature and sending pain signals.

Similar receptors and related ones can be activated by piperine in black pepper, the compound you might sprinkle on your eggs every morning.

When you consume these foods, your body heats up, as these receptors typically need temperatures above 42 degrees Celsius or acidic conditions to transform. However, capsaicin and other spicy compounds won't harm your tongue; you can eat as much as you like. You might notice that the burning sensation diminishes after consuming a lot of spicy food. This is known as capsaicin desensitization, a phenomenon that has intrigued scientists for a long time as they discovered that capsaicin can alleviate pain.

For example, capsaicin creams are used to treat arthritis-induced pain. The connection between receptors and pain perception is fascinating. Mint, which produces a cool sensation in contrast to the fiery heat of chili, is also due to a peculiar coincidence.

When there's mint in your mouth, the temperature in your oral cavity drops, triggering receptors.

Of course, all this isn't confined to your mouth. Similar receptors exist in your skin. If you bathe with peppercorns, you'll experience the same sensations, and rubbing your eyes with hands that have touched peppercorns will provide an unforgettable experience.