I have long used the saying "Music is my mind-altering substance of choice."
It has always been said as a bit of a joke-- because I tend to be "squeaky-clean" when it comes to addictive behaviors-- but there's actually a hidden element of truth there.
I do use music to keep my mind on track-- and I have, for a very long time.
We all know that music has the ability to "create a mood," and perhaps to bring up old memories. There are good reasons they use scene-specific music in movies, and good reasons why they play the music they play at airports, shopping malls and store. Your mind is "being influenced."
The same holds true for my wife-- who has the better known and more studied "conventional" ADHD with hyperactivity.
We both discovered-- independently of each other-- that techno and trance music (electronica) enables is to focus much better on repetitive and "long" tasks. Somehow, the upbeat, rapid drum-synth beat provides some kind of "brain interrupt" that improves out ability to focus.
What's particularly interesting about this is that even though we have quite different "variants" of ADD, we successfully incorporate listening to the same genre of music as "productivity tools."
Unlike her, however, I tend to use a more "chilled" or slower music style for when I write. It feels like it helps me access long term memories, while still staying awake.
It does make sense to me-- we "use" meditative styles of music in conjunction with hypnosis; at the same time, shamans use a repetitive drumbeat (very similar beats-per-minute as trance music) to induce altered mind states for people they are helping with things like soul retrievals and shamanic journeying.
Like other ways I have found to help me stay focused in life, I started "using" it as a therapeutic helping tool long before anyone diagnosed me with ADD.