December 22, 2025
As we return to work after New Years, there’s a phenomenal book that’s been on my mind: Stolen Focus by Johann Hari.
The insights in this book are impossible to ignore. Especially when it comes to how we work and focus in our daily lives.
What the research reveals about multitasking and distraction might completely change how you approach your workday.
The ideas in this book connect deeply with my own principles about intentional living.
IQ Drop
A small study commissioned by Hewlett-Packard looked at workers’ IQ in two situations:
- When they were not being distracted or interrupted
- When they were receiving emails and phone calls
The results were startling.
Technological distraction caused a drop in the workers’ IQ by an average of ten points. Just from getting emails and calls.
That’s twice the knock to your IQ that you get when you smoke cannabis.
So this suggests you’d be better off getting stoned at your desk than checking your texts and Facebook messages a lot. In terms of being able to get your work done.
From there, the research shows it gets worse.
Screw-Up Effect
The second way switching harms your attention is the screw-up effect.
When you switch between tasks, errors start to creep in. Errors that wouldn’t have happened otherwise.
I’ve written more about this in I Tested Google’s NotebookLM.
Here’s what happens: Your brain has to backtrack a little bit. It has to pick up and figure out where it left off. And it can’t do that perfectly.
Glitches start to occur.
Instead of spending critical time really doing deep thinking, your thinking becomes more superficial. You’re spending a lot of time correcting errors and backtracking.
Creativity Drain
Then there’s a third cost to believing you can multitask. The creativity drain.
You’ll only notice this one in the medium or longer term. But you’re likely to be significantly less creative.
Why?
Because where do new thoughts and innovation come from? They come from your brain shaping new connections. Connections from what you’ve seen and heard and learned.
Your mind needs free undistracted time. It will automatically think back over everything it absorbed. And it will start to draw links between them in new ways.
But if you spend a lot of this brain-processing time switching and error-correcting, you’re giving your brain less opportunity. Less opportunity to follow your associative links down to new places. Less opportunity to really have truly original and creative thoughts.
Diminished Memory
There’s a fourth consequence. The diminished memory effect.
A team at UCLA got people to do two tasks at once. They tracked them to see the effects.
The results? People couldn’t remember what they had done as well as people who did just one thing at a time.
This seems to be because it takes mental space and energy to convert your experiences into memories. If you’re spending your energy on switching very fast instead, you’ll remember and learn less.
Conclusion
So if you spend your time switching a lot, the evidence suggests:
- You will be slower
- You’ll make more mistakes
- You’ll be less creative
- You’ll remember less of what you do
The costs of multitasking are real and measurable. They affect everything from your IQ to your ability to innovate and remember.
The science is clear. Our brains simply aren’t built for constant task-switching and distraction. If you want to do your best work, create meaningful innovations, and actually remember what you accomplished, single-tasking is the way forward.
Want to read this book? Get your copy of Stolen Focus by Johann Hari here and discover more insights on how to protect your attention in a distracted world.