Laborious Learning

It is a common belief in educational circles that teaching people new ideas and facts works best when the learning process is made smooth and relatively easy. Teachers in schools usually assume that lessons have been successful when the concepts are easy to grasp—and today we have so many high-tech ways of simplifying learning, with computer graphics, animation, and other eye-catching techniques.

Yet current scientific research is showing that our brains respond better and learn more thoroughly when they face some difficulty. When classroom material is not easy to absorb, students tend to retain it better over the long run, as well as grasp it on a deeper level. It seems that when we force our gray matter to struggle, we actually become better learners. One experiment at Princeton University, for example, showed that students absorbed material to a greater degree when it was printed in a difficult font that forced them to work harder.

This result, of learning better when we struggle, is sometimes called “desirable difficulties,” to describe the idea that learning should be a challenge. Students at the University of Washington found that handwriting activated more of their brain than keyboard writing. Some teachers have noted that composing essays or poetry easily on computers—rather than experiencing the struggle of writing them out by hand—leads to much longer (and more boring) compositions.

Here are a few additional examples of laborious learning: The internet brings us riches of information, but it does not necessarily mean that we retain more knowledge or can express ourselves better. Hand calculators make an instant math whiz of anyone, and yet many youngsters today don't really grasp the mathematical concepts accomplished by that little whiz of a machine. Many artists find that their creativity is greater when they must struggle with the simple tools they have at hand, rather than gain access to high-tech tools. Modern recording studios offer a rich and easily accessible variety of electronic toys, which too often results in boring and pedestrian music.

When we face no obstacles—when life is easy—we are more likely to become unsure of what we really want or where we're headed. When we face distractions, however, it can cause us to dig a little deeper inside ourselves, to access greater cognitive ability. Our mind goes into high gear and we are more likely to generate unusual and creative connections, than when things are easy and our mind is on idle.

I'm an old man now. When I was a kid I remember my mom advising me that “you have to work hard in life, to get those things of value.” I guess Mom was either ahead of her time or was voicing an ancient truism that current scientific research is finding fascinating ways to validate.

Chickadee at the Feeder

He has just landed... his wings not yet folded. Click to enlarge.

Automatic Visual Smoothing

I wrote last time about how our brain receives a staggering amount of conflicting and imperfect information from our eyes, yet manages to sort it all out and provide us a reasonably accurate picture of our world. There's a similar task that our fabulous gray matter does, that helps us make sense or our world, in a slightly different manner. The brain receives a rapidly-varying amount of information. What keeps it from getting hopelessly lost in all the moment-to-moment jitter? Why doesn't the brain lose track of what our visual sense is trying to perceive, by getting confused with all the quivering information that comes in?

Recent research has discovered a key processing technique used by the brain, to keep from getting derailed by all the flickering data: our visual perception is strongly influenced by what we saw in the recent past—up to 15 seconds ago. The brain averages what's coming in at the moment with what it received 10-15 seconds ago. It's looking for consistency in our environment and throwing away the noisy, irrelevant stuff. It's smoothing or integrating the data, to pull out the necessary information that provides us a stable world.

By this process, the brain cleverly reduces the number of things we must deal with in our visual environment. Some researchers have dubbed it a “continuity field.” Think of approaching something on the ground when the light level is low. Is that a snake or coiled rope waiting there? As we cautiously proceed, many other visual signals get sent to the brain, but, remembering what we saw a few seconds ago, our attention hones in on the unknown object—ignoring extraneous information—until we see (whew!) that it's just a piece of rope. Our continuity field brought us the truth once again.

This phenomenon has another fascinating side to it. Because we pay attention to the one thing of interest, while we ignore the “clutter,” we become subject to what is sometimes referred to as “change blindness.” Trying to figure out if it's a snake or rope, we allow changes in our visual field—changes we're not expecting—to slip by unnoticed. We become blind to something that may, in fact, be intriguing, if not important.

For example, when movies are being filmed, numerous takes are often required by the director, to get the scene just right. The director—and later the editor—are focused on a particular desirable behavior of an actor, which they want to see. On the tenth take they may finally get it perfect—but something else has inadvertently slipped into the scene; an unexpected change that no one noticed. In take number 1, for example, the actor may have held a cup of tea, as he tried to respond to the director's guidance. By take number 10, the actor may now have his behavior perfect, but no one noticed that he now holds a glass of water. Change blindness has fooled everyone.

There's a famous psychological experiment in which subjects were directed to concentrate and count the number of times a basketball was passed between players with different colored shirts. Part way through the experiment someone dressed in a gorilla suit strolled slowly through the scene—even pausing to beat its chest. None of the participants ever saw the gorilla—so focused were they on counting. They had to be shown a film of the event to become convinced of their “gorilla blindness.”

Why do we miss the obvious? It's partly because of where our attention is directed, but also that our brain expects the world to follow certain rules—we believe that things don't arbitrarily change, while at the same time we know that inconsequential things can be ignored. But sometimes the world violates our rules, and because we're thinking so much about what happened 15 seconds ago, we miss an unexpected change. Be careful... next time that rope may actually be a rattlesnake.

Sweat Bee

Not sweet bee, but sweat bee.

Interpreting Eye Signals

Our brains receive massive amounts of information from our eyes. While that information has many distortions, alterations, and anomalies that the various components of our visual process creates, the brain has a marvelous way of massaging all those confusing and contradictory signals, to provide us a very workable representation of our world. Our eyes have several shortcomings that stem from either the fact that their capabilities are limited (for example, we lack Superman's X-ray vision or the ability to sense the infrared part of the visual spectrum, as some animals can), but mostly because of out-and-out “design” defects.

Evolution has done a magnificent job of gradually “designing” and developing our bodies over millions of years, acquiring some pretty amazing attributes along the way. But the evolutionary process is a sequential one that must add each tiny developmental step to those that went before. It is not a conscious process that has a goal, but a trial-and-error unfolding that must build upon what is already there. If an earlier incremental step worked in the past (that is, it previously was a useful addition to the organism), it gets locked in. There is no backing up and correcting an earlier innovation that does not make sense later on.

Our spine, for example, evolved to work well when we were moving on all four legs (and similar spines still do, for our horizontal mammal cousins), but when we came to stand up on two feet, the angle and curve of our spine created lots of aches and pains that a dog never experiences. But it's too late; evolution can't back up and start over, improving the basic design in the process. It's stuck with what is at hand.

Here are a few of the eccentricities of the human eye that got built in: anomalies that cause the brain to work hard to compensate:

1. Inverted retinal image—Light enters the eye through a lens. It is a physical property of lenses to invert the image, so the brain must correct for an upside-down signal. In fact, the brain must deal with two slightly different inverted images—one from each eye.
2. Eye movement—Our eyes constantly jitter about—several times a second. They send an unstable string of signals to the brain that must be accounted for by some sort of smoothing. The situation gets very complicated when we need to track a moving object across a stationary background. Somehow the brain compensates and gives us a stable visual world.
3. Blind spot—At the center of our retina a tiny signal transmission cable (that transmits visual information to the brain) does not allow the retina to register light falling on that point. This blind spot occurs at dead center of our visual field, but the brain compensates and provides us continuous coverage, even when the signal is absent at that point.
4. Obstructions—Between the lens and the retina is a jelly-like blob of fluid that is filled with various kinds of hindrances to the path of light. Nerve fibers, blood vessels, and those infamous floaters all get in the way and distort light waves, yet the brain manages to compensate for them and give us a clear image of what's out there... well, except for those pesky floaters, which flit around like little bugs in our field of vision.
5. Variable resolving power—Each eye has about 6 million cones clustered at its center. They are good at resolving detail and discerning color. Some 120 million rods encircle the cones. They are poor at resolution and are essentially color blind, but they do an excellent job at seeing in low-light conditions and noticing movement (which helped our ancestors to spot fast-moving threats like snakes and lions at the peripheral regions of their vision). The brain's job is to account for this varying resolving power and color sensitivity, to provide us an in-focus image, in all its color, across our whole visual field.
6. Depth vision—Each eye registers a two-dimensional image that is unable to distinguish between a close, small object and a farther-away, large object. The brain receives both (slightly different) two-dimensional images and creates a 3D version, giving us depth perception.
7. Time—Finally, the brain must account for the fact that light travels to our eyes at an incredibly fast speed (nearly 200,000 miles per second), but then the signal creeps along nerve pathways from our eyes to the brain (at about 50 feet per second). The result: our brain must adjust for the fact that the signal it receives is already history... it's nearly a half-second old. How does a batter in baseball manage to connect, when the pitched ball takes about that same amount of time to reach him? That wonderfully compensating brain again.

It is amazing that our sense of vision (which we rely upon more than any other sense) serves us as well as it does. In doing so, the brain must process conflicting signals from each eye that are distorted and incomplete, and give us a steady, flowing experience. This raises a final question: After all this processing by the brain, is the world we perceive in our head an accurate “picture” of what's really out there? Or do we experience an illusion—not at all like what the real world is?

These and similar questions are at the center of ongoing research into human consciousness. No, the world we perceive is not fully real—our senses cannot give us complete accuracy; just, it seems, the accuracy we need to survive. The world we perceive is a construct, but the system works for us. We manage to get along quite well with the visual world that our brain gives us—despite the conflicting information it receives from those odd sensing organs, the eyes. The brain essentially must make up a story, and it does a pretty good job of it.

Fringe Tree

As the photos show, fringe tree is a very good name for this Appalachia understory tree. The blooms smell heavenly... like the sweetest honey. It's in the olive family.

Backyard Ethology

For three decades now I have observed the local wildlife—in the woods, at the bird feeder, in the garden, and at any other nearby wilderness spot where nature's critters cavort. I have come to know and understand who they are and what they're doing, to a far greater degree than when I first moved to this rural retreat. I have learned much, but also understand that I've only begun to scratch the surface of fully appreciating my wildlife community.

There are two principle ways by which I've studied the local fauna: reading what scholars have written and through simple observation. I can gain much knowledge through surfing on the internet, and I have acquired a good-sized library of books on wildlife. They've helped me identify and learn a lot.

When I observe wildlife directly, I practice a form of ethology: the science of animal behavior—the whys and wherefores of their conduct and actions. An intimate understanding of their behavior comes from extended periods of observation—simply watching, while constantly questioning what is going on. It is crucial to keep an open mind, because so much can be missed if you decide too soon that you know what their actions are about, and thus close your mind to going any deeper. We humans have a propensity to anthropomorphize: attributing human behavior and characteristics to the animals. Even numerous scientists have made this mistake.

One of my champion ethologists is Jane Goodall, who spent decades patiently observing the behavior of chimpanzees in Africa. In her early years many esteemed zoologists rejected her conclusions about chimps' behaviors, but her keen observations gradually earned her an honored reputation and changed our comprehension of chimp culture.

As for what's going on with my local critters, I can get only so much from a book or Wikipedia. When I observe the particular behavior of a particular bird, it may be a general behavior of that species that I'm seeing, but it may also simply be how that individual has come to behave in my backyard. It is a unique being. The thing it is doing is unique. No other bird in the world is doing precisely what it is doing.

So I watch... and watch. What's going on? Can I be certain of what I perceive? Is it typical of this species I'm observing? Have I seen this particular bird do this before? What could be the reason for this behavior? The bird can't explain itself to me, so the keener my observation, the deeper I delve into its world. With understanding comes appreciation, awe, reverence... even love. The natural world possesses beauty beyond explanation. Give me three more lifetimes of sharp-eyed study and I'd still find myself a beginner.

Time to Move On

        Here are two photos of Carolina wren babies getting ready for life. The top photo shows five babies near a nest placed in the garden shed. Wrens like to locate their nests in odd locations. What's interesting is that the birds have left the nest for a spot on the shelf nearby. The parents were very upset with me when I took the photos. I tried to tell them that I'd not send them to the newspaper (but then violated my trust by posting them here).
         The bottom phot shows one fledgling a couple of days later, having flew from the previous perch to an overturned flower pot--just beginning to fly on its own, but not yet ready to leave the safety of the shed.