For anyone interested in this guy I recommend this ~3 hour long playlist, pick a video that looks interesting to you and check if you like his style. (It was recorded during a workshop (?) for parents.) https://www.youtube.com/playlist?list=PLzBixSjmbc8eFl6UX5_wW...
I can't agree strongly enough with this suggestion. Understanding the regulatory prefrontal cortex role in ADHD is key to getting a handle on the disorder, and Barkley does a fantastic job of presenting the evidence and conclusions.