Learning about the brain by dissection

Thirteen-year-old Scott Smith was surprised when he started to dissect the sheep brain. He said, "It was much softer than I thought it would be, sort of like Jello."

Scott and other 7th graders from North Kirkwood Middle School last month took part in a brain dissection experiment. They got their instructions from a Saint Louis University graduate student, via closed-circuit television.

The brain dissection was part of a 10-week brain study unit. The kids were studying the brain's structure and how it works. Each kid also will do an original research project about some aspect of the human brain, such as how memories are formed.

Scott and partner, 13-year-old Kurt Wunderlich, said they "had fun" cutting up the brain.

However, he said their dissection wasn't totally smooth. While taking off the tough outer lining of the brain, the "brain stem" separated from the lobes of their brain.

Some kids admitted they weren't quite so happy with the experiment.

Thirteen-year-old Zoe Hickox wrinkled her nose and used the term "interesting" when describing the dissection. She also said she has no interest in being a surgeon. "I'm going to be a lawyer," she said.

Allison Dickherber said, "It wasn't as gross as I thought it would be." She also said it was "actually fun."

Ms. Bonnie Nicholas' enrichment class was studying an anatomy of the brain curriculum from the Adventures in Medicine and Science (AIMS) program. It is offered by Saint Louis University's Practical Anatomy Workshop.

The SLU program offers classes on the human heart, eyes and spine. The heart classes include a dissection of a pig's heart. Kids in the eye classes dissect a cow's eye.

(If you're interested in such classes, why not ask your teacher to contact Karen Montgomery, the director of AIMS. Her phone number is (314) 535-4000 and her e-mail is montgokl@slu.edu.)

A SLU graduate student, Jay Nastav, gave the brain dissection instructions. He's studying anatomy and neurobiology at SLU. He's also planning to go to medical school.

Earlier, Dr. Paul Young, a SLU neurosurgeon gave a closed-circuit lecture on the workings of the brain. He used actual human brains to show kids which areas control speech, movement, eye sight and other brain functions.

He said each human brain has about 100 billion brain cells. He said the number of cells is the same in a small baby and a grown adult. But, what is different is the number of fiber connections between the cells. As you learn more, there are more connections formed.

Dr. Young described a human brain as "somewhat like a sponge" and "a little mushy."

The kids in Ms. Nicholas' class got to experience both the look and feel of a sheep brain during their dissection experiment.

Thirteen-year-old Grant Pope said, "I didn't know what the inside would look like."

His dissection partner, Craig Lieb, said, "I thought it would be all gray colored. But, there's a lot of white in there."

Allison Dickherber said, "I didn't realize there was so much fat in the brain." Their closed-circuit instructor told the kids the fat helps insulate the brain cells. Brain cells are very sensitive to heat and pressure.

While they were cutting into the brain, the instructor also had them notice what he called "the tree of life" inside the brain. Those structures look like a tree with a main trunk and lots of branches.

When the sheep brains were first passed out to the North Kirkwood kids, they looked smooth. But, that was because they were still encased in the protective film, the dura.

Once that outside layer was trimmed off, the typical brain structure with ridges and grooves showed up clearer. However, SLU instructor Jay Nastav showed how the grooves and ridges of the human brain were deeper and more numerous.

He said that was because the human brain had so much more to control than a sheep's brain. He said the human brain has a whole section just devoted to speech. "You don't carry on a conversation with a sheep," he said.

Of course, a dissection class wouldn't be complete without a mishap. After completely cutting up her brain sample, Amanda Prasuhn snagged her sweater on the edge of the dissection tray. That spilled the tiny brain parts all over the classroom floor.

The cleanup took some doing because the floor was carpeted.