variables that improve the ability to detect weak associations may improve insight solving. In short, insights tend to involve connections between small numbers of neurons....Just as it is hard to hear a quiet cell phone at a loud party, it is difficult to notice signals that have less energy than the general energy level already present in the brain. Hence, we tend to notice insights when our overall activity level in the brain is low. This happens when we’re not putting in a lot of mental effort, when we’re focusing on something repetitive
Which reminded me of one of my favorite Nietzsche quotes:
All truly great thoughts are conceived by walking.