Your are right that one meaning of “sensation” is related to the senses. But there is a second meaning as well: namely, “something that attracts a lot of attention and excitement from the public.” Maybe there is a relationship between the two words — because people use their eyes to see the thing creating the sensation, or their ears to hear it — but I’m not sure. For example, the book is a sensation or “creates a sensation” because lot’s of people are talking about it, or because you see articles about it in lots of newspapers, magazines, and blogs. Either way, you should accept the second meaning of “sensation.”

Why can we call a best-seller a “sensation”?