Body language and facial expressions have always been thought of as the prime channels for conveying emotion. But over the years we've learned that there are countless ways to manipulate them and mask what we really feel. Everyone has pulled a smile when they didn't feel like it, or acted like they were having fun when they actually just wanted to go home. It's almost instinctive.
But what about voice?
Turns out it's much tougher to disguise your true emotions when you speak. Not only do you have to measure what words you're going to say, but also control your facial expressions, body language, and several vocal cues—like pitch, cadence, speed and volume. It's a lot to spin at the same time, which makes your voice the most accurate medium for listeners to perceive your emotional state.