They guessed that they had found something interesting. When Avicenis analyzed the monitoring

They guessed that they had found something interesting. When Avicenis analyzed the monitoring data for several days, he found that the network remained at the same level of activity for short periods more often than for long periods. Later they found that small areas of activity are more common than large ones. "My jaw dropped," says Avicenis, because they first extracted a power law from their device. Power laws describe mathematical relationships in which one variable changes as the degree of the other. They are applied to systems in which larger scales, longer events are less common than small and shorter ones, but are not common. Per Buck, a Danish physicist who retired in 2002, first proposed power law as a distinguishing feature of all kinds of complex dynamic systems that can be organized on large scales and long distances. Such behavior, he said, indicates that a complex system balances and functions on the golden middle between order and chaos, in a state of "criticality", and all its parts interact and are linked for maximum efficiency. As predicted by Buck, sedentary behavior was observed in the human brain: in 2003, Dietmar Plenz, a neurophysiologist at the National Institutes of Health, observed that groups of nerve cells activated others, which in turn activated others, often launching systemic cascades of activations.