Zynga agreed to lock her out of her account but, Carrie says, she was able to log back in a couple of days later. “Zynga deliberately uses the same techniques that bookmakers do with slot machines to feed people’s addiction and now I find myself addicted with no way out,” she told the company. Where once she got her dopamine hit from online casinos and fixed-odds betting terminals (FOBTs), she now had mobile gaming. She craved dopamine, a chemical released by the brain that exacerbated by her ADHD. Carrie had begun playing obsessively through the night, spending thousands of pounds in the game and racking up huge debts.