The reasoning behind this seems circular and also not entirely true if I understand correctly . There are many many many cases of young children who stutter who are not aware of it until older and don’t display any feelings or negative emotions until later childhood. Secondly, having it be a neurological condition and then also saying it’s caused by emotional reactions seem contradictory. Yes emotions can exacerbate it but there’s little to no validated evidence as to say that emotions cause stuttering. Stuttering is not a learned behavior from high emotional situations which is what the 1967 article is essentially claiming. Also, stuttering has been tied to genetic inheritance within families, which explains the higher prevalence of people with multiple stuttering family members. It’s not from emotional disposition that is learned or taught. If I’m understanding the information correctly, which I may not be, it seems like stuttering supposedly is a learned process of speech which has been repeatedly disproven and moved away from in research. I am incredibly hesitant to support any of this information without seeing research to validate this information apart from a proposed theory.