Is your smartphone changing your brain chemistry? New research suggests that constant notifications from our devices makes our brains less efficient because we’re anticipating the next interruption. If you get nervous from not checking your phone, it’s because you’ve been hit with the stress hormone cortisol. Even worse, our brain feels rewarded each time we check our phones, thanks to the “feel good” hormone, dopamine. Trying to stop the cycle often leads to withdrawal symptoms. Experts say your brain needs downtime to get used to actually not being at work. I think I’ve just found a great excuse for not having a smartphone.