Michaeleen Doucleff

Plus, they added all these things to capture your attention and hold you there, like lights, sounds, flashing images.

So over the course of about 20 years, the industry gradually and purposely increased the addictiveness of these games by tweaking their features based on user feedback.

Wait, who gave the user feedback?

The gamblers.

The gamblers.

The casinos essentially ran these large-scale experiments on all the millions of people gambling each year in Vegas.

They tweaked the device a bit and then see if those changes increased the time people spent gambling.

Then they just repeated the process for decades.

So they were performing essentially massive A-B testing on gamblers.

Pretty much.

And the result was truly extraordinary.

The industry created devices that some people stay on for remarkable periods of time.

24 hours, 48 hours, uninterrupted.

Sometimes not.

That anthropologist we just heard from, Natasha Dalshall, found that some people wear adult diapers to the casino so they don't have to stop gambling.

One casino worker told her that each night a bunch of the machines sit out in an alley for cleaning because people have peed in them.

Yeah, and the power they have on people's time and money as well.

In her 15 years of researching, Natasha found four features that when combined together can trigger a trance-like state in people.

You lose track of time, where you are, what you're doing.

Scientists call this the machine zone or dark flow.