Forget Eyes—It’s the Brain That Sees - Pay a Visit to The Strange Thing that Lives Inside Your Head

Think: Why You Should Question Everything - Guy P. Harrison 2013

Forget Eyes—It’s the Brain That Sees
Pay a Visit to The Strange Thing that Lives Inside Your Head

Let’s take a look at vision. Have you heard the old saying, “seeing is believing”? Well, it’s often a case of believing is seeing. It is well known by researchers that what we think we see can be strongly influenced by images and ideas we have been exposed to previously as well as our own thoughts and imagination. This probably explains why it’s the people who already believe in ghosts or UFOs who keep seeing ghosts or UFOs, and why so few nonbelievers do. Seeing things that are not there can happen to anyone because the human brain constructs and interprets the visual reality that is around it. What we see is something the brain has produced for us based on input it received via the eyes. It’s never a 100 percent true and complete reflection of what our eyes are pointed at. For this reason, we can’t always be sure about what we think we see. Yes, that might be an angel that you see up ahead. Or your brain could be showing you an angel that it has mistakenly constructed out of a bush or some other object.

Construct and interpret reality? It sounds crazy when you think about it. We don’t really “see” the things we look at? How can this be? Most people probably assume that the brain simply shows us or somehow faithfully relays whatever images come in through the eyes. But that’s just not how it works. What actually happens is that light patterns enter the eyes and electrical impulses are sent along optic nerves to the brain. Then the brain translates these impulses into visual information that you “see” in your head. Your brain doesn’t reflect or replay the scenery around you like a mirror or a camera and monitor would. It provides you with its own highly edited and customized sketch of the scene. Your brain gives you a version of what you look at. It’s as if your brain comes up with something like a Hollywood movie production that is loosely based on what is really going around you. You are not watching a video feed; you are watching a docudrama. The brain takes the liberty of leaving out what it assumes are unimportant details in the scene before your eyes. Just like memory, this is not necessarily bad most of the time. In fact, it’s necessary in order to avoid information overload. You don’t need to see every leaf in every tree and every blade of grass in full detail when you look around a park. That would be way too much data. It would clutter your thoughts and make you less efficient, if not incapacitate you. What you need in order to walk through a park and function well is to have a general picture of your surroundings, so that’s what your brain gives you. If you need more detail, then your eyes and brain zoom in and focus on a single leaf or an individual blade of grass.

It gets weirder. Not only do our brains leave out a tremendous amount of detail, they also routinely fill in gaps in our vision with images that you can’t possibly “see” or that maybe don’t even exist in reality at all. Your eyes might not be able to track a fast-moving object, for example, so your brain will sometimes conjure it up and show it to you anyway, figuring that it might be useful to you to see a projected version of reality. The brain also fills in missing elements that “should be there” in static scenes because, again, it can help us to navigate our way through the environment. Magicians have known about this for many years. Even if they don’t understand or care about the science behind it, they take full advantage of the way our vision works when they do their sleight-of-hand coin tricks, for example. Again, our brains don’t do any of this for a gag or to make fools of us. They do it because it is the most effective and efficient way to function in life most of the time.

In addition to filling in missing images, our brains also find patterns or connect the dots when we look around. They do this automatically and do it very well. It helps us to see things that otherwise might be difficult or impossible to recognize. It’s probably one of the main reasons you and I are alive right now. Like many other animals, our prehistoric ancestors relied on this ability to eat and to avoid being eaten. When they needed to spot well-camouflaged birds and rabbits hiding in the bushes in order to avoid starvation, this ability to see things through clutter was crucial. It was no less important, of course, for them to identify the vague outline of a predator hiding in ambush in order to avoid becoming dinner in the short term and avoid extinction in the long term.

Although city dwellers rarely, if ever, find themselves in need of locating a predator lurking in the distance, this type of seeing still seems to be deeply ingrained. For example, a friend of mine who does long-distance open-water swims in the Caribbean told me that she does not suffer from shark paranoia, but, regardless of how she feels about it, her brain doesn’t take sharks lightly. When her head is under water during long swims, she says her brain’s visual system seems to be scanning constantly for the outline of sharks in the distance. And it often “sees” shark outlines if something even comes close to the shark template, she explained, although 95 percent of the time it’s nothing, not even a fish.

Michael Shermer, founding publisher of the excellent magazine Skeptic, has studied and written about this skill/habit/obsession of our brain for many years. He calls it patternicity. Defined as “the tendency to find patterns in meaningless noise,” Shermer says our brains do this so often and so well that they ought to be thought of as “pattern-recognition machines.”3 It’s all good, of course, right up until patternicity starts pushing us beyond reality and causing us to see too many things that do not exist. That’s when we get ourselves into trouble.

If I were walking in a forest at sunset and there was by chance a shadow that was vaguely shaped like a bear, my brain might instantly serve up a more complete and convincing image of a dangerous bear lurking in the dark. He’s not there, but I just saw him. I swear, I could even see his sharp teeth and menacing eyes! Now, if a bear really was there, my brain might have saved my life by alerting me. If no bear had been there, however, I was startled briefly and it’s no big deal. But what if I was certain I had seen Bigfoot, a demon, an alien, or a god? That might complicate my life unnecessarily. Shermer explains:

Unfortunately, we did not evolve a Baloney Detection Network in the brain to distinguish between true and false patterns. We have no error-detection governor to modulate the pattern-recognition engine. Thus, the need for science with its self-correcting mechanisms of replication and peer review. But such erroneous cognition is not likely to remove us from the gene pool and would therefore not have been selected against by evolution.4

On one hand, it makes sense for us to see some patterns of things that aren’t really there in order to be very good at seeing real ones that matter. On the other hand, we need to be aware of this phenomenon because it can lead to a confident belief in things that are not real or true. Additionally, patternicity is not limited to vision. It impacts hearing and thinking, too. Good skeptics understand how the brain often creates false patterns, so we know to be very cautious when considering claims of UFO sightings, for example, or anything else that is unusual. It only makes sense to be skeptical and ask for additional evidence when people claim to have seen or heard extraordinary things. Maybe they did, maybe they didn’t. Given what we now know about the brain, however, are you going to believe someone who tells you she saw a flying saucer or Bigfoot last week? She doesn’t have to be lying to be wrong. Anyone with perfect vision can see poorly. Anyone with a bright brain can think and come to the wrong conclusions. Anyone with an excellent memory can have wildly inaccurate memories.