Imagine yourself inside a room full of tunnels. You can look down any of them. Maybe you like this sense of freedom and maybe you also find it distracting.
But now you have your ADHD medication. Walls go up over all the tunnels except the one you’re facing.
When you turn your head, the wall for the last tunnel you faced slides up. The wall for the tunnel you now face slides down.
You can switch which tunnel you look down, but you can see only one tunnel at a time.
You can also see the tunnels with obstacles. The tunnels you may have avoided.
On medication, you find it’s easier to enter these previously-avoided tunnels (maybe because the more appealing tunnels have their walls up, keeping their temptations out of sight).
And once you enter one of these “harder” tunnels, the medication helps you stay there.
This is part of the experience of ADHD medication for many of those with ADHD, on the one that’s working for them.