Why is that significant? “Our cortex is already changing the raw visual information before that information gets into our consciousness,” Voytek concluded.

You’re not only seeing what is actually before you; you’re seeing what your brain is telling you is there.

Specifically, the cortex is sending a cascade of predictions about what should be seen at all the different layers of complexity. So what travels back up from the eyes is not raw visuals of the environment, but how the world deviates from what the brain is expecting.