Stuttering is a physiological diorder at its core, with many psychological layers. It is a well documented fact that many stutterers do in fact stutter way less or don't stutter at all in certain situations. Such as but not limited to: Talking to themselves, talking to animals, whispering etc The fact remains that stuttering has an unknown cause and each stutterer is unique. I went to camperdown and it has shown some improvement. But of course, my stutter remains. Situations of high stress can definitely make it worse. This is the psychological aspect of it. Although, if you realise, people do stutter even in very comfortable situations such as talking to parents and close friends. I believe over time, certain patterns reinforce themselves. Some people may find ordering coffee to be very challenging. Some people maybe find certain letters to be challenging. This can eventually cause an anticipation of a stutter when the person realises that certain word is coming up. Even if they have be relatively fluent all along. Many have told me stuttering may be purely psychological, and it may be. But current research shows no strong evidence towards that.