30. The Brain's Dark Energy
On p.158 of The Mind of God, it is noted that our brains function at one tenth capacity, in a similar proportion to what is thought to be the visible portion of the universe (one tenth visible). This concept has been given some strength by recent discoveries of neuroscientists. Using MRI scans, scientists have discovered that the brain uses up to 20 times more energy at "rest" than it does when one consciously acts. Noting the terminology of Astronomy, they have called this the brain's "dark energy." More formally titled the DMN, or default mode network, it represents different areas of the brain that "chatter away" to each other when one is either asleep, daydreaming, or under anesthesia. It has also been noted that, of the 10 billion bits of information reaching the retina of the eye each second, only six million bits leave the retina because there are only one million output connections in the optic nerve. Only 10,000 bits reach the visual cortex of the brain. After more processing, it is thought that only 100 bits per second are consciously perceived. The number of synapses or contact points between neurons devoted to incoming visual information is less than 10% of the synapses present in that area of the brain. In other words, there are far more brain connections used to process the data than there are to collect it! As the ancient philosophers recognized, our brain may limit or prevent us from knowing what is really out there.
(The Brain's Dark Energy, by Marcus E. Raichie, Scientific American; Mar. 2010, Vol. 302, Issue 3, p. 44-49)