This is a very interesting paper. Thanks for sharing. It's interesting that animals show stuttering-like behaviours. I have long thought that stuttering is not simply a dysfunction of the speech production parts of the brain, but must have correlates in non-human animals. The impact of gut microbiome on neurodevelopmental disorders as well as mental health has been increasingly explored in recent years. Personally, I have found great benefits to my mental health and, by extension, to my ability to speak, by dramatically reducing my intake of refined sugar and ultra-processed food. This study doesn't give information about food intake, but eating a healthy diet is worthwhile for anyone. The paper mentioned that brain scans of PWS show higher levels of iron, which suggests that it may not be metabolised efficiently. I wonder if there's a connection between iron intake and stuttering.