Most biological, social, and psychological systems are based on interactions between an activator and an inhibitor. The patterns which emerge depend upon the relative rates at which the activator and inhibitor spread. Three main cases occur, depending on whether the activator's diffusion rate is much less than, roughly equal to, or greater than the rate at which the inhibition spreads. In these three cases we observe, respectively, isolated patches like zebra stripes or leopard spots, moving complex patterns like Belusov-Zhabontinsky scrolls, or seething chaos. Applying this to the activator-inhibitor patterns in the human brain, if you inhibit new thoughts, you are left with a few highly stimulated patches: obsessions and fixed ideas. If you manage to create new thought associations at about the same rate you inhibit them, you develop creative complexity. And too high a rate of activation leads to unproductive mania. Exercise: apply this notion to spread of good and bad news in society.
Rucker's Law of Morphogenesis