So, completely on accident and at the age of 32, I suddenly discovered this week that you can taste things with the underside of your tongue.
First, I took a salty tortilla chip, lifted my tongue and stuck it underneath, being certain that it didn't touch the top of the tongue. I held it under my tongue and discovered that I could definitely taste the saltiness of the chip. In fact, it tasted great!
I haven't experimented with other taste sensations yet (sweet, sour, etc.) but I will get to work on it and keep you updated.