Not knowing when a stimulus is going to happen also triggers a dopamine release. This is why when our phone buzzes we usually instantly look at it. It's a thrill of finding out who wants to talk to us. This is considered a Pavlovian Reflex.

Research shows that dopamine is most effective when released in small amounts, such as a limited character count (Twitter).

These releases can motivate us to search more, look through more tweets, pictures, and posts, which all feed back creating a dopamine loop. These loops are most easily broken by stepping outside and giving technology a break.