Perception's Seat

The Neurological Underpinnings of Perceptual Intelligence

You're walking alone through a forest late on a windy night. You've been through these woods many times before and know the way, but you've never done so by yourself, and certainly never after dark. You arrive at a clearing and see something unusual in the distance. It blocks your path, so you proceed cautiously while squinting in the darkness to determine what lurks there. Suddenly, you freeze as you see the form take the shape of a large animal; its skin glistens in the moonlight. You can feel its glowing eyes bearing down on you, sizing you up and preparing to attack. Its razor-sharp fangs jut out. It approaches you, and your heart races while you debate whether your action will be fight or flight. As you are about to make a run for it, the creature lunges right at you and your reflexes kick in to protect your face. You scream at the top of your lungs until you realize that you have been scared out of your wits by a plastic garbage bag full of leaves and twigs that had been caught in a gust of wind. Brushing off the refuse, you laugh at yourself for having thought this stupid garbage bag was a monstrous animal. You continue on your way.

In this scenario, at what stage did your perception of the animal originate? Were you expecting to see something dangerous because you were alone in this dark forest for the first time? When the object first appeared in your line of vision, did you tense up and become fearful?

Misperceiving the bag reflects poor PI in that situation. From the beginning, the menacing object was merely a plastic bag full of leaves and twigs. It was harmless all along, but in the absence of light you couldn't discern what it was; then your imagination kicked in, filling in the missing details. Innumerable memories might have kicked in, presenting subliminal messaging: perhaps you had seen a horror film in which someone was attacked by a hideous animal in the woods; you may have read something in the news about a predator on the loose in that forest; when you were a child, perhaps your mother warned you about never going into the forest because she had a relative who had been harmed there by a wild animal; or, as is quite common, the forest evoked sinister images from fairy tales like "Little Red Riding Hood" or literary classics like Sleepy Hollow.

Every individual perceives things differently. The same circumstances may produce wildly different interpretations, depending on one's PI. Another person might have been in the same situation as you but determined right away that the bag was a harmless object taking the shape of an animal. On the other hand, a third person venturing forth might have panicked and closed his or her eyes the entire time out of fright. The plastic bag and its contents would have hit his or her unprotected face dead-on, causing scratches and bruises. This terrified individual would scurry off and post a story on the Internet about having been attacked by a supernatural monster.

In this chapter we will explore the world of human perception: what it means, how and where it originates, and how the brain functions and tries to make sense of it all.

Are We All Trapped in a Matrix?

In 1999 Andy and Larry Wachowski created an enormously successful science fiction film called The Matrix, which starred Keanu Reeves as Neo, a man who discovers that the world we live in isn't real. The human race is actually part of a vast computer simulation in which people's energy is being used to power machines ruling the "real world." While in the Matrix, everything humans experience is convincingly real; they see, feel, touch, taste, and smell everything. Their memories and emotions all originate from what occurs in the Matrix, and this has been their perception of reality for years ... until Neo joins a rebellion and battles to free the minds and bodies of humanity to join the real world, no matter how dark and precarious it might be.

The film's executive producer Andrew Mason distilled the movie down to this: "[It] is the question of whether or not what I am experiencing right now is real." The Matrix, of course, is just science fiction. (I hope — how would we prove otherwise?) But the notion that we might not have control over our perceptions or that we aren't living in the "true reality" is a fascinating one. As with the scenario of the bag of leaves, can we be so easily fooled?

Our brains are obviously our primary "matrix" and vital to our perception of the world around us at all times. The rest of our body sends inputs to the brain — from pain to pleasure and everything in between — which in turn responds with interpretations of them; not only does it tell us if and how we should react, but it stores the information for later recovery and analysis.

The brain is an organ, though it is often called a muscle because it "performs work" and rules all other muscles from its perch in the skull. The brain can be dissected, measured, and studied. But there's also something we refer to as the "mind," which gives rise to our consciousness. Unlike the brain, the mind is transcendent and nonquantifiable. Neuroscientist Sam Harris describes it as "what it's like to be you." Unlike a kidney, heart, or lung, you can't transplant consciousness from one person into another.

The vexing question is: What role does the mind play in perception and PI as opposed to that played by the brain? Is the mind the seat of perception within the brain itself? Perhaps it is microscopic or even invisible and located within some lobe or synapse? Or does it reside somewhere else?

These questions are further complicated when we add the body to the equation. Sometimes it seems the body is just the brain's personal chauffeur. But recent studies in neuroscience argue...