Default Mode Network
Also known as: DMN
The brain network that lights up when you're daydreaming, reflecting, or imagining the future — your mind's 'background processing' system.
A network of brain regions that becomes most active when you are NOT focused on the outside world — during daydreaming, mind-wandering, remembering the past, and imagining the future. In ADHD, this network may be unusually active even during tasks that require focus, contributing to mind-wandering. It is also associated with creativity and self-reflection.
How it works
When you're not focused on a specific task, this network takes over — processing memories, thinking about others' perspectives, and planning ahead. In ADHD, this network may not quiet down properly when focus is needed, which explains why daydreaming intrudes during tasks.
Think of it like
It's like a screensaver that's supposed to stop when you start working, but sometimes keeps playing over your spreadsheet.
What it feels like
You drift into thought mid-conversation or mid-task, not because you don't care, but because your background processor is louder than most people's.