I discussed the circuitry involved and I linked a paper that provides the evidence for the mechanisms in a post I made. Here's a link to that post: [https://www.reddit.com/r/Stutter/comments/1hpmdhg/dopamine\_and\_its\_role\_in\_stuttering/?utm\_source=share&utm\_medium=web3x&utm\_name=web3xcss&utm\_term=1&utm\_content=share\_button](https://www.reddit.com/r/Stutter/comments/1hpmdhg/dopamine_and_its_role_in_stuttering/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button) Here's another link for a review on pharmacological research in stuttering - There is a ton more research but this is a good place to start. [https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2020.00158/full](https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2020.00158/full) Please note that the post and the review mainly discuss how increases in dopamine can lead to stuttering. Low dopamine represents a different set of consequences to the circuitry I laid out in the post but it can also lead to stuttering too.