At least 15 percent of human females possess a genetic mutation that gives them an extra (fourth) type of color photoreceptor - and this allows them to discriminate between colors that look identical to the majority of us with a mere three types of color photoreceptors.
David EaglemanThe conscious mind is not at the center of the action in the brain; instead, it is far out on a distant edge, hearing but whispers of the activity.
David EaglemanAfter all, across the population there are slight differences in brain function, and sometimes these translate directly into different ways of experiencing the world. And each individual believes his way is reality.
David EaglemanIf an epileptic seizure is focused in a particular sweet spot in the temporal lobe, a person wonยดt have motor seizures, but instead something more subtle. The effect is something like a cognitive seizure, marked by changes of personality, hyperreligiosity (an obsession with religion and feelings of religious certainity), hypergraphia (extensive writing on a subject, usually about religion), the false sense of an external presence, and, often, the hearing voices that are attributed to a god. Some fraction of historyยดs prophets, martyrs, and leaders appear to have had temporal lobe epilepsy.
David Eagleman