In a recent study, participants listened to sentences read by two different people and were asked to judge which one was taller. Nearly two-thirds of the time, they correctly identified the taller talker. That’s significantly better than chance, which means there’s some voice-height connection. You know how blowing into a bottle makes a sound that gets lower the less liquid there is inside? The researchers think a similar principle, applied to a sound produced deep in the lungs, called subglottal resonance, could explain the height effect.

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