Brain Rules (Updated and Expanded)

Brain Rule #8
Stimulate more of the senses at the same time.
•
We absorb information about an event through our senses, translate it
into electrical signals (some for sight, others from sound, etc.), disperse
those signals to separate parts of the brain, then reconstruct what happened,
eventually perceiving the event as a whole.
•
The brain seems to rely partly on past experience in deciding how to
combine these signals, so two people can perceive the same event very
differently.
•
Our senses evolved to work together—vision influencing hearing, for
example—which means that we learn best if we stimulate several senses at
once.
•
Smells have an unusual power to bring back memories, maybe because
smell signals bypass the thalamus and head straight to their destinations,
which include that supervisor of emotions known as the amygdala.

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vision
Brain Rule #9
Vision trumps all other senses.

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WE DO NOT SEE with our eyes. We see with our brains.
The evidence lies with a group of 54 wine aficionados.
Stay with me here. To the untrained ear, the vocabularies that wine
tasters use to describe wine may seem pretentious, more reminiscent of a
psychologist describing a patient. (“Aggressive complexity, with just a
subtle hint of shyness” is something I once heard at a wine-tasting soirée to
which I was mistakenly invited—and from which, once picked off the floor
rolling with laughter, I was hurriedly escorted out the door.)
These words are taken very seriously by the professionals, however. A
specific vocabulary exists for white wines and a specific vocabulary for red
wines, and the two are never supposed to cross. Given how individually we
each perceive any sense, I have often wondered how objective these tasters
actually could be. So, apparently, did a group of brain researchers in
Europe. They descended upon ground zero of the wine-tasting world, the
University of Bordeaux, and asked: “What if we dropped odorless, tasteless
red dye into white wines, then gave it to 54 wine-tasting professionals?”
With only visual sense altered, how would the enologists now describe their
wine? Would their delicate palates see through the ruse, or would their
noses be fooled? The answer is “their noses would be fooled.” When the
wine tasters encountered the altered whites, every one of them employed
the vocabulary of the reds. The visual inputs overrode their other highly
trained senses. Folks in the scientific community had a field day.
Professional research papers were published with titles like “The Color of
Odors” and “The Nose Smells What the Eye Sees.” That’s about as much
frat-boy behavior as prestigious brain journals tolerate, and you can almost
see the wicked gleam in the researchers’ eyes. Studies such as these point to
the nuts and bolts of Brain Rule #9. Visual processing doesn’t just assist in
the perception of our world. It dominates the perception of our world.

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Not like a camera
Many people think that the brain’s visual system works like a camera,
simply collecting and processing the raw visual data provided by our
outside world. Seeing seems effortless, 100 percent trustworthy, capable of
providing a completely accurate representation of what’s actually out there.
Though we are used to thinking about our vision in such reliable terms,
nothing in that last sentence is true. The process is extremely complex,
seldom provides a completely accurate representation of our world, and is
not 100 percent trustworthy. We actually experience our visual environment
as a fully analyzed 
opinion
about what the brain thinks is out there.
It starts with the retina, vying for the title of amateur filmmaker. We
used to think the retina acted like a passive antenna in an automated
process: First, light (groups of photons, actually) enters our eyes, where it is
bent by the cornea, the fluid-filled structure upon which your contacts
normally sit. The light travels through the eye to the lens, where it is
focused and allowed to strike the retina, a group of neurons in the back of
the eye. The collision generates electric signals in these cells, and the
signals travel to the back of the brain via the optic nerve for analysis. But, it
turns out, the retina isn’t just waving through a series of unaltered electric
signals. Instead, specialized nerve cells deep within the retina interpret the
patterns of photons, assemble the patterns into a collection of “movies,” and
then
send these movies for analysis. The retina, it seems, is filled with
teams of tiny Martin Scorseses. These movies are called tracks.
Tracks are coherent, though partial, abstractions of specific features of
the visual environment. One track appears to transmit a movie you might
call