It's been about 15-minutes since you've checked your smartphone. Do your fingers itch to pick it up? You try to resist, but pangs of anxiousness gnaw at you until finally, you give in and check your favorite apps.

It's not just you. Former Google product manager, Tristan Harris, told Anderson Cooper in a recent 60 Minutes interview that Silicon Valley is engineering apps, smartphones, and other devices to get you hooked. Some programmers call it brain hacking: programmed methods of hijacking peoples' minds to form a habit. In response to your behavior, design techniques are embedded inside the products to make smartphones so appealing that you will use them, and other devices, more often.

Most people check their smartphones at least every 15-minutes; even when no notifications have prompted them to pick it up. This habit is so deeply ingrained that it's likely your cortisol levels will rise if you ignore the urge, making you mildly anxious and distracted. Of course, you want to get rid of the anxiety, so you grab your cell phone and immediately feel at peace.

Obviously, having your nose in your smartphone doesn't do much for you socially, but the frequent overload of cortisol caused by anxiety poses a health risk. While we need cortisol, as it has many functions, elevated levels interfere with learning and memory, lower immune function and bone density, increase weight gain, blood pressure, cholesterol, and odds of heart disease. It also increases risk for depression and lowers life expectancy.

Harris calls the use of brain hacking techniques a race to the bottom of the brain stem. The closer the tech companies can get you to fear, anxiety, and loneliness, the closer they are to winning the race for your frequent attention. Why is it so important? With advertisers spending more than thirty-one-billion-dollars, the aim to please them is high.

Programmers use a playbook of techniques to keep the addiction going, according to Harris. As an example, Snapchat, the app that teens rank as "most important social network," according to a Piper Jaffray report, is keeping teens hooked by design. Snapchat knows that teens don't want to break their streaks--the number of days in a row two people have volleyed photos back and forth. Reportedly this is causing kids such great stress that they give their password to friends to keep the volley going on their behalf when they go on vacation.

Anderson refers to it as an addiction code. With every chance to receive cute emoji's, Facebook likes, retweets, and mentions we are being conditioned by rewards, and thousands of engineers work diligently to update your phone daily to be more and more persuasive.