Attention has 4 opportunities per second to change

The spotlight of attention is more like a strobe, say researchers

The researchers use different metaphors to describe this throb of attention, including a spotlight that waxes and wanes in its intensity. Four times per second — once every 250 milliseconds — the spotlight dims and the house lights come up. Instead of focusing on the action “onstage,” your brain takes in everything else around you, say the scientists.

“The question is: How can something that varies in time support our seemingly continuous perception of the world?” said Berkeley’s Randolph Helfrich, first author on the human-focused paper. “There are only two options: Is the data wrong, or is our understanding of our perception biased? Our research shows that it’s the latter. Our brains fuse our perceptions into a coherent movie — we don’t experience the gaps.”

Perhaps some experience some of those gaps :)