Tuesday, November 23, 2010

'Brain: The Inside Story' of an Incredible Organ

The anatomical illustration by Vesalius, above, shows the brain as the hub of the nervous system, a branching network of nerves that links all the parts of the body and connects with the outside world. Photo from AMNH/D. Finnin.

AS I write this story on my computer keyboard I am eating slices of Granny Smith apples. I know that I am eating a Granny Smith, of course, because I can see that it is green and can taste that familiar tart flavor.

I am also able to see it and taste it because of the workings of my cortex. This wrinkly part of the brain regulates not only my ability to see and taste, but to feel, hear and smell. Signals are sent to my visual cortex and gustatory cortex, where I receive the message that I am eating a Granny Smith instead of a Royal Gala.

Similarly, I am able to type without looking at the keyboard (except for the numbers) because in my high school typing class I repeatedly practiced where the letters are positioned on the keyboard. If I touch the "R" key instead of the "T" key, for instance, I know something is amiss because I have memories of the location of each key in my basil ganglia. This area in the center of the brain stores memory of routine activities such as typing or tying shoelaces.

No doubt I learned such scintillating facts in my high school science class – or was it junior high? In any case, it was not presented in such an accessible, interesting and interactive fashion. The world has the American Museum of Natural History (AMNH) to thank for “Brain: The Inside Story” on view until 14 Aug. 2011. Very few who pass through New York will have an excuse to miss this expansive showcase because it will be up for nearly nine months. Online visitors will not get the full experience but will surely sense the extraordinariness of it. (See various videos and slideshows: http://www.amnh.org/exhibitions/brain/videos.php)

“I want people to change when they go through the exhibit, curator Rob DeSalle said during remarks at the press preview last week. RDeS is also a researcher at AMNH’s Sackler Institute for Comparative Genomics. “I want people to think better after they go through the exhibit.”

Using hand-recognition technology, this interactive exhibit helps visitors understand how neurons communicate with each other at high speeds using thin spindly branches called dendrites that constantly change shape and sprout new shoots. Photo by AMNH/D. Finnin.

"Brain: The Inside Story,” offering some of the latest information and newest perspectives on the workings of a complex organ, is divided into seven sections. “Your Emotional Brain,” for example addresses how the brain processes emotions, while “Your 21st-Century Brain” takes into account advancements that can help the deaf, blind and epileptics.

Enter the exhibit, and welcome to the “Introduction" section. In a small case on a pedestal in Daniel Canogar’s brain installation is a human brain preserved using some sort of silicone technique that is beyond easy comprehension by the lay mind. It weighs about three pounds and is utterly captivating. One is compelled to get as close to the glass as possible and to move around the pedestal for the very best vantage point for observation. Equally captivating is the installation itself. It is a darkened space filled with 1,500 pounds of cable-like wire extended from a frame near the ceiling to the floor. The wires are tangled, twisted, contorted and intersected. Beads and shards of light move rapidly over the wires. Together, they represent the brain’s pathways and the myriad electrochemical signals therein that help the human perform any number of functions like walking and chewing gum at the same time.

Along with a couple of dozen other journalists, Yours Truly opted for a tour behind the scenes led by scientists, including one who studies the brains of birds. Another, John Maisey, curator in the AMNH’s Division of Paleontology, has learned that brains can fossilize and has proof in the form of the skull of a 300-million-year-old fish with a brain-shaped structure at its center. He is absolutely giddy about this find - in Kansas of all places. “I suspect that the brain was not preserved on its own,” said JM, who has the look of a mad scientist about him. “I believe it was eaten by another animal to have remained intact.”

During a fascinating visit with the rather telegenic Mark Siddall, curator in the Division of Invertebrate Zoology, the group had the pleasure of seeing parts of an octopus, squid and sponge. All are preserved in alcohol. The one live creature was a leech – or rather several. While theirs are not as complex, leeches have more brains than humans – two to be exact. A front brain and a back brain, both of which they require for survival. It is the rear brain that informs the bloodsuckers when they have had their fill.

Heretofore, none had seen a diagram of a lobster brain but plenty had clapped eyes on a dead lobster, though not as big as the one MS keeps in his lab. Incidentally, the lobster brain does allow it to have the sensation of feel. Yes, when they are dropped into boiling water they do feel the heat. Because it is unbearable they faint, MS said. The result is tough meat. For better results he recommends “putting them in cold water and bringing it to room temperature” and then heating it up. An even better result is to cut it down the middle. Either way it does not bode well for the lobster, no?

In the theater presentation on the brain and brain function, a clear resin 3D brain that lights up relevant brain areas is synchronized with a video that follows Lea Elizabeth Ved as she auditions for Julliard. Here, the amygdala lights up to signal her nervousness. Photo by AMNH/D. Finnin.

Back out front at the exhibit, once a visitor moves out of the brain installation the next stop is the “Introductory Theater” section. On view is a huge brain made from resin that lights up to show which parts of her brain Lea Elizabeth Ved, shown on an adjacent video screen, is using during her dance audition for Julliard. It and the human diagram on the edge of the installation are not to be missed. The two are what primary school education is to the rest of formal education. Good primers, both as they prepare visitors for success when they stop by the build-a-brain interactive exhibit ("Your Emotional Brain" section) and language acquisition interactive ("Your Thinking Brain" section). "Your Sensing Brain" section is the home of the waterfall illusion. One sees a waterfall but is that the sound of a waterfall being piped out of the speaker. Is the mind playing tricks or are tricks playing the mind?

At the human diagram in the intro section one learns that the spinal cord is “the main highway of the nervous system.” In other words, it carries signals from the body to the brain and from the brain to the body. (The brain stem connects the spinal cord to the brain and the rest of the body.) Knowing this puts into perspective what doctors mean when they declare a patient brain dead.

Unlike LEV, a brain dead person does not have the capacity to become nervous during a dance audition or on any other occasion. Her fit of nerves is triggered when a stem cell sends a message to her limbic system, the place where emotions are triggered and memories are processed. Also stored in this bank, viewers learn from the video clip, are memories of the numerous occasions her dance instructor reminded her that she knows the routine well (stored in her basil ganglia). This has a calming effect. All the while, the various parts of her brain in play as she moves or feels light up on the resin model. LEV finishes the audition and is pleased with her performance. She will remember it a long time. Specifically, this memory resides in the amygdala section of her limbic system. The memory of her acceptance at Julliard is stored there, too.

Every second a neuron (brain cell) may send as many as 1,000 signals regarding memory of any number of sensations and all brain functions. It is through neurons that messages are transported throughout the nervous system, from the body to the brain, within the brain and from the brain to muscles and organs. That's why it takes more than eyes to see, ears to hear and so on. These electrochemical signals zip from neuron to neuron by way of a connection called a synapse at speeds up to 250 miles (400 kilometers) an hour. See a visual illustration of this at the neuron gesture table in the “Your Sensing Brain” section and be mesmerized by the speed of the movement of neurons when a hand is placed on the table, as well as the spidery forms created by the contact. The brain allows humans to experience their environment as an integrated whole because of the constant signals (traffic) therein.

A floating projection of fMRIs (functional images of the brain) in the Brain Lounge tells the story of four people performing differnt activities. Photo by AMNH/ R. Mickens

This notion is best articulated in this sensing brain section. Take sight for instance. Of course, one sees with one’s eyes. However, eyes (through the retina) respond to patterns of light by sending electrical signals to one set of brain cells. The cells (thalamus) take the signals and relays them to other cells (visual cortex) down the line that sense shape, color and movement. Piece by piece the brain puts together the scene that we see, whether it’s grass, an apple or an obscured image of Jay-Z's spouse. At another station in this section the viewer is challenged to identify the portrait of a certain lady with a sly smile from piecemeal visual cues.

Brain areas are devoted to seeing, smelling, tasting and touching. “They communicate,” according to ‘Brain: The Inside Story’, "like parts of an orchestra, so that your experience feels rich, seamless and complete.”

End "Brain: The Inside Story” in the Brain Lounge. Take a load off on white latex-like benches arranged around a projector shaped like a tabletop. View the brain scans of a few people at work, including a United Nations translator switching easily from Arabic to English, as well as those of a New York Knicks basketball player as he reacts to making a basket and the resultant crowd response. Swoosh!

Visit http://www.amnh.org/ to learn more about “Brain: The Inside Story, including hours, admission, gift shop, etc.

1 comment :

  1. After a lovely week and a lovely evening with Bill and Anne on Sunday we awoke today to rain and we were also a bit hungover after a lot of drinking and putting the world to rights.

    ReplyDelete

 
Creative Commons License
VEVLYN'S PEN: The Wright take on life by Vevlyn Wright is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License .
Based on a work at vevlynspen.com .
Permissions beyond the scope of this license may be available at vevlyn1@yahoo.com .