S: Well… They are .. um… like wires carrying electrical signals and when the electrical signal reaches a contacting point, then a message sent out to another Neuron. And I think the interesting thing about Neuron is that ( the professor cut in …. )
P: Yes exactly…. That’s fine, Bernard. Today I wanna to discuss cells found in the brain, they are called Glial Cells. Um…Just to let you know, there are different types of glial cells, but we’ll discuss the specific types later.
P: Right, Glial Cells, so, first off, historically speaking, um… I am talking about the 1950s here. Researchers didn’t think the glial cells were that important. They always focused on neurons… neurons…neurons… the thinking was that neurons are responsible for all the communications going on within the brain. As far as the glial cells concerns, early researchers just thought glial cells supporting the a few jobs like, carrying nutrients to neurons because in order to keep functioning, brain cells need energy. And another job …um… protecting brains from invading agents of diseases. You know… um.. things that the immunes system should have discovered and captured, but didn’t.
P: So, again, early researchers assumed that the main purpose of glial cells was to support neurons. With their support, neurons could make connecting, with their support, neurons can make the connections … um… like to think, feel, remember or even eat a sandwich. So, the thinking was why study glial cells? These days though, there’s new thinking of gial cells. In recent researches we discovered and the exchange of information, communication between brain cells and the glial cells throughout once lifetime. So, instead of glial cells having just an unimportant role, we see them communicating; actually having impact on the connection of Neurons, swaying them, determining which connection go stronger and which one go weaker. So, there are really three communication networks or communication systems in the brain. Neurons communicate with neurons, glial cells communicate with glial cells and then glial cells communicate with neurons. In other words, glial cells do much much more than previous thought. At least, that’s what the recent researches showing. And where will the new understanding of cell function lead us? Well, we don’t know. It’s very exciting. And the really marvelous part is glial cells outnumber the neurons’ in brain by far. But they’ve barely been explored. Brenda, you have a question?
B: So, the research field in glial cells is growing?
P: I think there’s a lot of opportunity in glial cell research, especially a few years from now when you folks graduated. As I see the field is really opening up.
P: But, let’s go back a little and analyze. Why did we miss so much about glial cells in the past? Well, we have incorrect assumptions about glial cells. We knew how signals travel through neurons and assumed that glial cells would use the same mainly electrical mode of transmitting information. But they don’t. Again, just as Bernard explained. Neurons mainly use electrical activities to carry the messages. Glial cells though, glial cells use chemicals, not electrical signals to carry messages. And since our basic assumption back then was wrong, we missed out the real understanding. And there’s still a lot we don’t know.
B: What else can glial cells do? Can they repair nerve damage for instance?
P: We’ve been still asking questions, experimenting and learning. Some people have an extremely high numbers of glial cells more than normal, more than the typical person’s brain has. One question we have does a person with higher number of glial cells in brain mean greater intelligence? And there are different types of glial cells, so maybe being genius is caused by having an unusual high number of them or maybe just have a certain type. We don’t know yet. As we gained answers to these questions what would we be able to do that we couldn’t do before? Well, perhaps someday we would be able to utilize glail cells to treat injuries. Some scientists are doing experiments on that possibility now.
S: But what do you think Dr. Zoller?
P: Well…I think ….. Yeh… soon there would be something accomplishing new things in science and in the field of medicine as we gained a deeper understanding of how the brain works.
P: Does anyone have any questions? No? We will move on to different types of glial cells then.
Q1. What does the professor mainly discuss?
○ How two types of brain cells were discovered.
○ Brain cell research in the 1950s
○ How the understanding of glial cells has changed.
○ The role played by glial cells in determining human intelligence.
Answer: how the understand of glial cells have changed
Q2: Historically, what does the researchers assumed the main purposes of glial cells?
○ Repairing nerve damage in the brain
○ Exchanging information with neurons
○ Supporting the needs and activities of neurons
○ Determining the strength or weakness of neuron connections
Answer: supporting the needs and activities of neurons
Q3: Early brain researchers focus on Neurons, what does the professor imply was the results of the emphasis?
○ New methods were found to treat injured brain cells
○ Little research was done on glial cells
○ A relationship between intelligence and the number of brain cells is established.
Answer: little research was done on glial cells
Q4: According to professor what kind of discovery let the researchers to gain a better understanding of a role of glial cells?
Answer: glial cells use chemical signals to send messages
Q 5: Listen to part of the conversation, and then answer the question.
When the electrical signal reaches a contacting point, then a message sent out to another Neuron. And I think the interesting thing about Neuron is that ( the professor cut in …. )
P: Yes exactly…. That’s fine, Bernard.
What does the professor imply when she says this “Yes exactly…. That’s fine, Bernard.”
Answer: Bernard’s answer is complete
Q 6: What does the professor imply when she says this “I think there’s a lot of opportunity in glial cell research, especially a few years from now when you folks graduated. As I see the field is really opening up.”
○ The student considers working in glial cell research as a career
○ Research are starting to reveal the results of their work on glial cells
Answer: The student considers working in glial cell research as a career
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