Not all flavors hit the brain with equal force. When blindfolded participants taste sugar, salt, lime juice, and bitter chocolate one at a time, most identify bitter chocolate as the strongest. That result suggests the tongue sends more intense signals to the brain for bitter flavors than for sweet or salty ones.

The tongue does not respond to every flavor equally. Blindfolded participants tasted four samples one at a time — sugar, salt, lime juice, and bitter chocolate — rinsing between each. They reported which taste felt the most intense. Most identified bitter chocolate as the strongest. The results show that the tongue may be more sensitive to bitter flavors than to sweet, salty, or sour ones.