The electrical messages bouncing across your brain at any given time outnumber the messages zipping through the world’s telecommunications networks. All that activity requires enough electricity to power a dim light bulb. That might not sound like much until you consider the brain uses 20 percent of the body’s energy but is only about 2 percent of its weight.
The brain consumes a huge amount of energy compared to other organs, 20–25% of total consumption, whether we are resting or physically active, and despite being only 2% of our total weight. Most vertebrates devote 2–8% of total energy to their brain, but in primates the percentage is much higher, with humans using the most. From this we can probably conclude that high energy use is a requirement for intelligence.
Picture Credit : Google
