According to a new brain study, the sensation of eating Szechuan peppercorn is the equivalent of 50 light taps on the skin every second. In other words, ingesting spicy Asian food is a lot like getting groped.
Chili picture from Shutterstock
In a bid to better understand how the brain constructs sensory experiences, researchers from University College London analysed the somatosensory perception of tingling in humans by applying Szechuan peppers to participants' lower lips.
At the same time, the 28 participants were tasked with comparing the frequencies of mechanical vibrations applied to their right index finger to the 'pins-and-needles' sensation on their lips. The study found that the application of Szechuan pepper mimics the sense of physical touching (and lots of it):
Szechuan pepper is common ingredient of many Asian cuisines, known for the characteristic tingling feeling it causes in the mouth. Here, we show that this tingling is due to the Szechuan pepper sending the equivalent information to the brain as a light tap on the skin at the rate of 50 times per second.
By using an unusual chemical stimulus to activate a class of tactile receptor, we have been able to identify a discrete population of ‘labelled lines’ in the somatosensory system, based on their psychophysical properties.
The report concludes that the specific somatosensory effects of Szechuan pepper may contribute to flavour in a similar gastronomical manner to colour, temperature and sound. (i.e. -- By mimicking touch, spicy food boosts taste perception for a fuller sensory experience.)
What's the spiciest food you've ever eaten and how frazzled did you feel after the first taste? Share your experiences in the comments section below.
Food vibrations: Asian spice sets lips trembling [Royal Society, Biological Sciences]