Some of these questions are hard to answer. It would be easier for me to describe how it "feels" to have ADHD if I had any idea how it felt not to have ADHD. As for my experiences with ADD ... well, that would be my life story. I decided to tackle this by considering my subjective experience of the world -- how I perceive it, internalize it, interact with it.
What I wrote is still pretty long, so I apologize if you have ADHD and find it overwhelming. To help with that, I've broken it into sections, which are titled in bold face. The sections describe my unmedicated brain on those rare "good" days, and then my unmedicated brain on "bad" days (which was most of them). This is followed by an attempt to put the ADD experience into an analogy that a non-ADDer might understand. Finally, there is a section about my experience with my ADD medication.
The Adult ADD Brain, Unmedicated: On Good Days
I have the "inattentive" subtype of ADHD. Some people refer to this as "ADD" -- attention deficit disorder -- because inattentives are not hyperactive. Referring to us as having "Attention Deficit Hyperactivity Disorder" seems kind of silly.
Before I was on medication, my good days were kind of like snorkeling. I love snorkeling. The whole point is just to let yourself drift and watch the pretty fish as they swim into your view. If you see a particularly interesting fish, you can follow it, until you see an even more interesting fish. Then you follow that one for awhile. No pressure to *do* anything in particular.
My mind does this sort of thing naturally. It drifts from one thought to another, with no particular place to go. If someone says to me, "what are you thinking about?", it takes great effort to remember where my mind had gotten off to and to tell them. Sometimes I can't do this at all.
When I'm in this state, I usually feel vaguely like I should be doing something, but I can't think of what it is, or if I can, I can't motivate myself to go do it. This is true even if I'm trying to accomplish something I enjoy. The process of getting off the couch and, for instance, going into my art studio, and mixing up some paint, and then painting something, is just too much to think about. I don't get a lot done in this state.
The Adult ADD Brain: On Bad Days
Most days, of course, I don't have the option of letting my mind drift. I really am supposed to be doing something. A shift at work (back when I had such things), errands to run, chores to do. Most days, the knowledge that I should be doing something -- and the fact that I can't remember what that something is -- overwhelms me enough to cause significant anxiety.
What am I supposed to get done today? I can't remember ... did I write it down somewhere? If so, where's the list? How can I find it in all this mess?
OK, I've got a few hours before I need to be at work. I know I'm supposed to drop off some packages on my way to my shift ... dammit, and there was something else I meant to do. And there's that curriculum I'm supposed to write up by Monday. And also that deadline for the art show; I need to finish that piece and then actually mail in the application.
God, I really need to vacuum in here. But I'd need to pick up all this crap first. And I should eat lunch before I do anything else. Eew, the kitchen counter hasn't been cleaned in I-don't -know-how-long! Where would I even start doing that? OK, OK, I'll have to deal with that later. Right now I'm hungry. I need to eat eat lunch, and I need to do that now. And I should really check my email while I'm eating ...
So I check my email. The things on my to-do list fade into the background. I click on an interesting link my friend sent me, and then on an interesting link in that article; then my interest in a completely unrelated topic is piqued. Before I know it I'm running late from work -- and dropping off the packages is out of the question.
OK, But What Does It Actually Feel Like?
Imagine you're working on an important and complicated project that's due tomorrow morning. In your workspace there's a TV that's receiving an image from one station, a ghost image from another station, and the audio from a third station. The radio is on too. Also, someone is running a vacuum cleaner. The phone rings, and you need to take an important call. Outside, someone keeps riding their Harley up and down the block while blasting their custom sound system at full volume. And the power company is doing something with a jackhammer, right outside your window.
That's what ADD feels like. Everything competes for your attention, and you are simply unable to screen any of it out to work on what's important (assuming you can even figure out what's important to begin with).
Now, imagine you can make this all go away just by putting down your work and playing a video game. Or reading a book. Or surfing the web. Or, for that matter, mixing a stiff drink or smoking a joint.
This is why I got distracted by my email a couple of paragraphs up. The internet is a pretty absorbing place, and while I'm surfing it all of the stress, all of the overwhelm, simply goes away. This also illustrates a very important point, and something most non-ADDers just don't understand -- when we look like we're "wasting time", we're actually self-medicating. Sometimes, we self-medicate by using drugs or alcohol; chemical dependency is common in people with ADHD. We're doing whatever we can to make the horrible sensory and cognitive overload just go away.
This issue causes a lot of friction between those with ADD and those without. "You can concentrate when you really want to," they say to us. "You spent hours playing that video game. Now you're trying to tell me 'you didn't have time' to take out the trash like I asked you to? You're lazy. You're immature. You're just downright selfish!".
Thanks. That sort of thing helps a lot.
Adult ADD on Medication
I started taking Vyvanse for ADHD about two and a half years ago. Vyvanse is a long-acting amphetamine that stays in your system for several hours (many people, like me, are lucky to get all-day coverage). Nonetheless, it's pretty much a fancy version of speed. In most people, speed improves cognitive performance, but usually at the cost of feeling jittery and unable to sleep.
Within a few hours of taking my first dose of Vyvanse, I suddenly realized that I felt calm. It was remarkable. I could look around my living room and observe the piles of books and papers, but I wasn't overwhelmed by them. I considered the piles and what to do with them, and realized that I wasn't quite up to dealing with them just yet. I would leave them as they were for now, and that was OK.
I went into my kitchen and saw the mess on the countertop. I remained calm. I decided to clean it, and was able to see that the first step was to put the dirty dishes in the dishwasher. The next step was to clean the dishes that needed to be washed by hand, dry them, and and put them away. By that point the countertops were clear, and I could thoroughly clean them. This took awhile, because I hadn't done it in quite some time, but I didn't get distracted in the middle of the task. Then I ran the dishwasher. And, lo, my kitchen was clean!
Then, that night, I fell asleep much more easily than usual, and I slept unusually well. That's what amphetamines do to my brain. I'd like to be able to tell this to every person who claims that ADHD isn't "real" because everyone gets improved performance out of stimulants. Does "everyone" sleep better on stimulants? No? Didn't think so.
As I titrated up on the Vyvanse, I continued to improve. I was able to prioritize, to break tasks down into manageable sequential steps, and then carry them to completion (instead of doing about 80% of a task and then getting bored or overwhelmed). I even learned to manage my time by breaking my days into chunks like "work", "computer time", "exercise", "chores", and "art". I even found I could be more social -- I could follow the conversation at a party, because I could tune out all the conversations going on around me.
Basically, my ADHD meds help me to function like a real, grown-up person. Right now, I'm struggling with a mutant mood disorder, relationship problems, and family drama; this, of course, has had an impact on my cognition, motivation, and ability to plan. Sometimes I forget things, but I'm more or less able to go about my day. If it weren't for my ADD medication, this would be impossible.