Very much like in case the with both stuttering and dyslexia, I proposed that there might be a positive correlation between the presence of traditions of vocal polyphony and the later acquisition of phonology by children. This idea was the third offshoot of my idea of asynchronous shift to the speech of different human populations. You can see here relevant excerpts from my 2006 and 2011 books.
- “My child said today ‘biscu-it’: Cross-Cultural Aspect of the Acquisition of Phonological System” from the 2006 book Who Asked the First Question?.
- “Acquisition of the Phonological System” excerpt from the 2011 book Why do People Sing?.