Hi there, I just joined so I could add to this thread.
I feel there is some clarification needed here. ADHD is the updated and correct way to refer to this condition. ADD is not longer being used by physicians or psychologists, but it is still very commonly used to refer to ADHD-PI (predominantly inattentive) or some people call it the "passive" ADHD.
I grew up with this condition. However, since there were no awareness of it when I was growing up, I struggled not knowing about that the challenges I was facing had nothing to do with lack of will or laziness. Fortunately for me, I had a good surrounding and my condition is moderate. ( I was able to keep my jobs, relationships, etc).
I was diagnosed being an adult, and with this information I was able to read about the condition and develop some strategies to deal with it. I am also having medication that has really helped especially at work.
I also know that it is hereditary. My 7 year old son also has it.
ADHD is a disorder, but it has some interesting characteristics. Basically we struggle to control the thoughts that appear almost simultaneously in our minds and drift from one thought to another causing sometimes feeling overwhelmed and unable to act. We struggle to control our impulses , and that is why we have difficulties focusing. We can focus, but for that we need to be very very motivated with the task at hand.
Once we develop certain techniques, we can take advantage of this condition as it is a perfect situation for creativity work. Personally I deal with my flavor of ADHD by keeping two lists. One is the todo list that keeps me in the path of what I need to do (Smartphones are very good for this). Checking the items in this list prevents me to drift away from my tasks. The second list which is very important, is where I write down all those thoughts that come to mind while I am performing the main task. Here is where I get the most of my condition as this is the creative part. Since I wrote down the idea, I can continue working on what I was doing. Once I finish, I can check out those notes and usually they are incorporated later in my todo list.
I don't believe there is a relation between having ADHD an being INFJ. Maybe there could be some personality traits that develop in a child as a response from the mind to the ADHD condition (like introversion), but they surely are also dependent on the surroundings, each person's mind may decide to cope with the condition differently.
Cheers,
Obijuan