I read the most fascinating analysis about ADHD from a highly regarded (and highly compassionate) Canadian physician, Gabor Maté. He says ADHD traits like tuning out and distractibility first develop as emotional defense mechanisms against distress (anxiety, sorrow and pain). The stages go something like this:
As a child:
You grow up in a stressful parenting environment (abuse, addiction, poverty, etc.)
You can't fight back, escape or ask for help
While your brain is developing—you tune out
The tuning out gets wired into your brain
The tuning out becomes the "default setting" of your brain
As an adult:
You're diagnosed with ADHD
Unfortunately, we don't yet know if ADHD is a permanent condition. For example, how malleable is the brain in adulthood? One thing seems to be certain: Expose yourself to a more nourishing environment and it leads to positive changes in the structure of the brain of adults.
I've suffered from ADHD for as long as I can remember. And yes, I grew up in a very stressful environment, impoverished—with parents and siblings fighting all the time. There is one positive, though. The little focus I do have goes to things that are very important to me—that I'm interested in—such as educating myself about ADHD, Depression and Anxiety, as well as my few hobbies, such as photography, screenwriting and filmmaking.
The British Psychiatrist R.D. Laing wrote that there are three things human beings are afraid of:
Death, other people, and their own minds.