The science of learning is, at bottom, a study of the mental muscle doing the work the living brain and how it manages the streaming sights, sounds, and scents of daily life. That it does so at all is miracle enough. That it does so routinely is beyond extraordinary.
Think of the waves of information rushing in every waking moment, the hiss of the kettle, the flicker of movement in the hall, the twinge of back pain, the tang of smoke. Then add the demands of a typical layer of multitasking say, preparing a meal while monitoring a preschooler, periodically returning work emails, and picking up the phone to catch up with a friend.
Insane.The machine that can do all that at once is more than merely complex. It’s a cauldron of activity. It’s churning like a kicked beehive.
Consider several numbers. The average human brain contains 100 billion neurons, the cells that make up its gray matter. Most of these cells link to thousands of other neurons, forming a universe of intertwining networks that communicate in a ceaseless, silent electrical storm with a storage capacity, in digital terms, of a million gigabytes. That’s enough to hold three million TV shows. This biological machine hums along even when it’s “at rest,” staring blankly at the bird feeder or some island daydream, using about 90 percent of the energy it burns while doing a crossword puzzle. Parts of the brain are highly active during sleep, too.
The brain is a dark, mostly featureless planet, and it helps to have a map. A simple one will do, to start. The sketch below shows several areas that are central to learning: the entorhinal cortex, which acts as a kind of filter for incoming information; the hippocampus, where memory formation begins; and the neocortex, where conscious memories are stored once they’re flagged as keepers.
The entorhinal cortex does one thing, and the hippocampus does another. The right hemisphere performs different functions from the left one. There are dedicated sensory areas, too, processing what you see, hear, and feel. Each does its own job and together they generate a coherent whole, a continually updating record of past, present, and possible future.
In a way, the brain’s modules are like specialists in a movie production crew. The cinematographer is framing shots, zooming in tight, dropping back, stockpiling footage. The sound engineer is recording, fiddling with volume, filtering background noise. There are editors and writers, a graphics person, a prop stylist, a composer working to supply tone, feeling the emotional content as well as someone keeping the books, tracking invoices, the facts and figures.
And there’s a director, deciding which pieces go where, braiding all these elements together to tell a story that holds up. Not just any story, of course, but the one that best explains the “material” pouring through the senses. The brain interprets scenes in the instants after they happen, inserting judgments, meaning, and context on the fly. It also reconstructs them later on what exactly did the boss mean by that comment? scrutinizing the original footage to see how and where it fits into the larger movie.
It’s a story of a life our own private documentary and the film “crew” serves as an animating metaphor for what’s happening behind the scenes. How a memory forms. How it’s retrieved. Why it seems to fade, change, or grow more lucid over time. And how we might manipulate each step, to make the details richer, more vivid, clearer.
Remember, the director of this documentary is not some film school graduate, or a Hollywood prince with an entourage. It’s you.
The science of learning to take just one implication casts a different light on the growing alarm over distraction and our addiction to digital media. The fear is that pulled in ten directions at once by texts, tweets, and Facebook messages, cannot concentrate well enough to consolidate studied information. Even worse, that all this scattered thinking will, over time, somehow weaken their brains’ ability to learn in the future. This is a red herring. Distractions can of course interfere with some kinds of learning, in particular when absorption or continued attention is needed when reading a story, say, or listening to a lecture and if gossiping on social media steals from study time. Yet we now know that a brief distraction can help when we’re stuck on a math problem or tied up in a creative knot and need to shake free.
In short, it is not that there is a right way and wrong way to learn. It’s that there are different strategies, each uniquely suited to capturing a particular type of information. A good hunter tailors the trap to the prey.