The Emotional Channel

Researchers call the voice the "leaky channel" because it reveals emotional information that speakers often try to conceal.

The vocal channel runs independently of your words, carrying a parallel stream of emotional data that is hard to fake and impossible to fully suppress. That is the heart of why the voice matters so much: every time you speak, you are sending two messages at once. One you choose, and one your body sends whether you want it to or not.