I turn off (or down) the radio when I'm driving and trying to look for an address in an area I'm not familiar, around accidents, detours, where I need full concentration. If you ask me a question about minutiae that requires some serious thinking, I may close my eyes to dig info out of my memory because I can think better without the visual distractions.
In the heyday of stereo systems, I read numerous reviews of equipment where the listener would be in a dark room or closed eyes to be able to discern the difference between to phono cartridges for example. Subtle differences that the brain couldn't pick out with the added data from the eyes coming in. I like to think of the brain as a CPU and all the senses take clock cycles. That's why people on cell phones drive like they have been drinking.
I have had several neurological tests done where they did dim the lights and said the results would be better if I fell asleep on one test, another test she said she would be asking goofy questions and feel free to just give a nutty answer. I don't do nonsense stuff well so asked her what the objective was. She said to keep my brain busy while they ran the test (with a bunch of wires hooked up to my head) and I could say anything, so I proceeded to tell her how I troubleshoot the stuff I work on. She said it worked and she learned something<g>.
YMMV...not in neuro field but spent numerous hours with a few of them.