Doug Noll teaches two exercises to sharpen emotion recognition: listen to radio ads and identify feelings from voice alone, then watch muted actors and read emotions from their bodies. Train both your ears and eyes.
Chapters
One practice is if you're listening to a radio commercial or on, um, I like radio best, even though people don't listen to radio much anymore. I like radio best because there's no visual. And what you're going to try to do is in that 15-second spot, how many emotions can you identify? Hmm. That's one. The other exercise is to turn down the volume on your screen and watch actors play out a scene and identify from their body language what emotions they're portraying. And these two exercises train— the audio exercise trains your ear to listen to tonality and speed and timbre, which all convey emotion. And the visual exercise teaches you how to pay attention to nonverbal cues.