Dr. V. Ramachandran and Sandra Blakeslee, in their book, Phantoms in the Brain, say it nicely (p. 134). "At any given moment in our waking lives, our brains are flooded with a bewildering array of sensory inputs, all of which must be incorporated into a coherent perspective that's based on what stored memories already tell us is true about ourselves and the world." Imagine the incredible volume of detail available to our brains each second. The art of successful living is knowing what to ignore. People who lack this skill quickly become dysfunctional. They appear overwhelmed, unable to make decisions, even lost. We often give them psychiatric labels.
Inventing story is the default mode of our brains. Whenever we encounter novel data, we make up a story to explain it. Story is also the most efficient way to store information. For example, the story about Pocahantas contains vastly more information than a 20 digit number, but is much easier to remember.
Ramachandran and Blakeslee (p. 89) say, "The mind, like nature, abhors a vacuum and will apparently supply whatever information is needed to complete the scene""If a person having a migraine attack glances around the room and his scotoma [blind spot] falls on a large clock or painting on the wall, the object will disappear completely. But instead of seeing an enormous void in its place, he sees a normal looking wall with paint or wallpaper. The region corresponding to the missing object is simply covered with the same color of pain or wallpaper." This illustrates what we do so expertly revise the world to fit our expectations. We can do this because we are always one step removed from the world. We are seeing the world through a map (or a story) created by our brains to explain the barrage of perceptual information flooding us at any instant. When necessary, we invent. People with Korsakoff's syndrome are a marvelous example of this. These people suffer from the inability to transfer short-term to long-term memory based upon a thiamine deficiency, often related to excess alcohol intake. When asked a question, they completely seriously invent wonderful and usually plausible answers, which change each time the question is asked, for they don't remember what story they've already told. And, given the nature of social interaction, they feel compelled to answer the question, which usually requires the invention of a story.
Ramachandran and Blakeslee say, "In order to generate coherent actions, the brain must have some way of sifting through the superabundance of detail and of ordering it into a stable, internally consistent "belief system' a story that makes sense of the available evidence." As we grow up, we absorb the stories told to us by the important people in our lives. These are the stories that have survival value those that keep us safe. Stories that help us understand that we can't fly, what might happen if we play in the middle of a busy street, and even why not to be outside after dark.
However, some of the stories we absorb are not necessarily helpful or even shared by much of the world. Many people object to the Taliban story about women. Yet, to those children who grow up within these stories, their truth seems self-evident. Gender roles arise from stories into which we are born and are quite arbitrary in many ways.
Ramachandran and Blakeslee say, "Each time a new item of information comes, we fold it seamlessly into our preexisting window." Generally, we incorporate new data into the existing stories by which we are already living. It would be terribly inefficient for our brains to have to revise all of our stories everytime we receive new information, so generally we modify the information rather than our stories whenever possible. This explains how people come to "twist the facts". We need to do this for efficiency of brain function. Fact twisting is occasionally glaringly obvious in medicine. A colleague of mine recently ordered a patient out of his office when she told him her cancer had gone away. "No it hasn't," he shouted. She came to see me in tears. In fact, her MRI scan had revealed a complete absence of tumor. My colleague couldn't accept her explanation that a traditional healer had cured her. Therefore, he insisted that her cancer had not gone away. He couldn't incorporate this fact into his relatively rigid story that said that traditional healers are quacks who don't do anything to help real disease.