Hypothesis for Scientist Dr. Edward Paginilli's Experiment

"My hypothesis is that the tongue has specific regions that only can taste sweet, bitter, sour, and salty."

I agree to this hypothesis because when I did the experiment with the vinegar, sugar, salt, and black coffee, I seemed to taste stronger tastes on the different bits of the tongue for each flavor. Although I couldn’t taste it that well in general for some of the things I could taste, I tasted it more strongly on a certain bit of the tongue, than overall. Even though I did taste it more on the certain places, you could still taste it on other places, I believe there’s not only one particular part that you can taste the sweetness, or saltiness etc. So I believe the hypothesis above is correct but incorrect.