At the University of Minnesota, they've been doing studies on gamblers like Theodore. And they think what they've found can explain other obsessions too.

It appears that people who have a difficulty with compulsive shopping, compulsive gambling, even people who go to sporting events compulsively, all have a similarity in brain circuitry.

In gamblers like Theodore, a casino triggers the release of neurochemicals that stimulate the areas that process pleasure and urge. This is the way we all recognize and enjoy pleasure. But in people who get obsessed, this process seems to physically change their brains. The pleasure pathways start to, dominate, and any tiny reminder of a casino sets off an uncontrollable urge to gamble. It's these abnormal changes which scientists here believe cause obsessions.

What these changes result in then is behavior that seems to take on a life of its own. It actually can't be controlled by the person on a conscious, voluntary basis. The person, if you will, actually becomes a sort of robot to their brain, which has a life of its own.

If I'm 100% honest, I don't ever want to stop gambling. It's so exciting and so invigorating when I'm there. I don't know what I would be able to put in its place. But it is an obsession. And it's destroying my life.

Desperate to control his gambling, Theodore has enrolled for an experimental treatment. He'll be given medication to block the pleasure giving chemicals in his brain.

The medication that we use affects chemicals in your brain. It will decrease your urges to gamble. It will also affect the pleasure that you receive from it.

If it suppresses that pleasure—

Mm hmm?

I mean, how is that going to affect my everyday life?

You're not turned into a zombie who can't experience pleasure. What this does is it dampens the pleasure associated with the pathological behavior. In this case, that's the gambling.

The medication Theodore's been prescribed is normally used to treat drug addiction. But his gambling has such a grip that he'll need a much higher dose than even a hardened heroin addict.

I take one pill for the first five days. And then after that—

The treatment is so new, no one really knows what the optimum dose should be.

And then after that, they'll decide. Regulate it from there. It could be up to three pills.

This is the medication for the obsession.

The university has asked Theodore to keep a daily record to see if the drug is working.

I laid there and I thought, I can't fall asleep. Everybody else is asleep. I want to go to the casino.

The thoughts of gambling, going to the casino to have something to do have been in my mind quite a bit. I was able to actually not go, even though I had almost $40 in my pocket.

Saturday night, I just urged over and over and over. It was so bad when I went to bed that I couldn't sleep. I ended up going to the casino. Monday I started taking two pills, and the urge, even the thoughts, haven't been there.

Five weeks later, Theodore, still on medication, is searching for something to replace the thrill he used to get in the casino. He used to be in the military flying in helicopters. He's taken to the air again to try to get the same buzz.

Something like flying over the Grand Canyon, I don't think it would be able to fulfill the same rush that I get from gambling. It's different. I would probably have to get in the helicopter, fly over the Grand Canyon, zoom in, zoom up, down, go through the turbulence, all of it to be able to equate with the same thrill and excitement that I get from gambling.

But is the thrill and excitement still there? Theodore is in for a shock. Now on the highest possible dose of his anti-obsession drug, he decides to test out his reactions to the casino.

My hands used to shake. I'm not sweating.

Also a big thing about me walking into a casino would be this overwhelming feeling of I'm home. I'm comfortable. This is where I am. This is the most comfortable place that I ever am.

And I did not have that sense walking in here today. And that, to me, that's huge. Because that was the whole draw.

How can this one little pill do all of this? And I have to admit, in a lot of ways, I'm amazed.