Let me address your examples above: - We don’t stutter when we’re alone because there’s no conversational aspect to our speech - We don’t stutter when we sing because there’s constant airflow, and it uses a part of the brain not associated with stuttering - We don’t stutter when we whisper because the whispering doesn’t open the vocal folds enough for a stutter to even exist However, I think he’s on to something. If we tell ourselves we will stutter, we gain a lot of anxiety for fear of stuttering. This severely tightens the facial muscles and vocal folds, therefore causing a stutter.