This Is Your Brain Under Anesthesia

When you are awake, your neurons talk to each other by tuning into the same electrical impulse frequencies. One set might be operating in unison at 10 hertz, while another might synchronize at 30 hertz. When you are under anesthesia, this complicated hubbub collapses into a more uniform hum. The neurons are still firing, but the signal loses its complexity. A better understanding of how this works could make surgery safer, but many anesthesiologists don't use an EEG to monitor their patients.