Years ago, I had a young colleague who would steal a glance under the table at his WhatsApp every minute or two.
Today, that behavior has gone mainstream — many of us work with constantly buzzing notifications from apps like Slack and Microsoft Teams.
In this post, I would like to share the science explaining why that is a terrible idea.
When we work on any task, it activates a corresponding neural circuit/network in our brain. And when we switch our attention, our brain has to suppress the previous circuit and amplify another brain circuit, corresponding to the new task.
Unlike an electric switch going on and off, this process in our brain is messy. It is a bit like erasing and writing on a whiteboard again and again, which leaves a residue, making it hard to read.
In our brain, this exact thing happens. When we switch tasks, the brain networks corresponding to the previous task are not fully switched off. Hence it leaves a residue — Prof Sophie Leroy called it ‘attention residue.’
So with two different brain networks simultaneously activated, our brain is neither here nor there. That is why we feel scattered.
Here is what it does to you:
- You feel unfocused
- You struggle to grasp complex concepts or summarize information. If you have ever had to read the same paragraph in a book again and again, you know that feeling.
- You become inefficient and error-prone.
- You exhaust your cognitive resources, leading to stress and overwhelm
But this isn’t all the bad news. There are two more reasons to avoid multitasking:
- Zeigarnik Effect: Our brains tend to remember unfinished tasks better than completed ones. When you switch tasks midway, the lingering thoughts of the previous task will haunt you, diminishing your focus and productivity.
- “The 25-Minute Trap”: Prof. Gloria Mark found that it takes an average of 25 minutes to come back to the original task after switching. This 25-minute duration may vary, but the trap is real.
In short, the more you have to do, the less you should multitask. But what do we do? Exactly the opposite.
Talk about irony.
– Rajan