Written in layman terms that are approachable/readable: 2016 - [Seeking Clues to Stuttering Deep Within the Brain](http://dana.org/News/Seeking_Clues_to_Stuttering_Deep_Within_the_Brain/) 2011 - [Using Brain Imaging to Unravel the Mysteries of Stuttering](http://dana.org/Cerebrum/2011/Using_Brain_Imaging_to_Unravel_the_Mysteries_of_Stuttering/) Also, some of Steven Pinker's writing on language development (like *The Language Instinct*) may indirectly educate you on this topic. It doesn't focus specifically on stuttering, but learning how age impacts language development (for example) may provide insight into stuttering's heritability. And I'll second [Dennis Drayna's](https://www.nidcd.nih.gov/about/staff/dennis-drayna-phd) research. His publications are listed at the bottom of that link.