But dopamine is only part of the story. Each time you switch between tasks—say, from writing an email to checking Instagram—your brain doesn't make a clean transition. Research from the University of Washington reveals that a residue of your attention remains stuck on the previous task. This "attention residue" can persist for up to 23 minutes, meaning you're never operating at full cognitive capacity.
Picture your attention like a computer with multiple browser tabs open. Even when you're focused on one tab, the others continue running in the background, slowing down your entire system. The average knowledge worker switches between apps and websites over 300 times per day. That's 300 opportunities for attention residue to accumulate, creating a fog of semi-distraction that persists throughout your day.