During the 1980s and 1990s, scientists made dramatic strides in our ability to detect the brain’s activity. Magnetic resonance imaging (MRI), positron emission tomography (PET), single photon emission computed tomography (SPECT), and magnetoencephalography MPG), are relatively recent inventions that have enabled us to map the brain’s electrical activity, and we are actually able to watch the brain think in real time. Neuroscientists have estimated that over 90% of what we know about the brain, we have learned in the last 20 years. Perhaps even more startling, is that much of what we thought we knew about the brain turns out to be false.