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Interested in continuing education? Here's some good news. As this ScienCentral News video reports, brain researchers have uncovered one mechanism that controls how our brains make new connections.
Branching Out
Our ability to learn new things depends on the expansive network of "wires" inside our brains. Luckily, that network keeps growing throughout our adult lives.
"The brain is very dynamic," says Bonnie Firestein, professor of cell biology and neuroscience at Rutgers University. "You have billions of nerve cells. And while you're an adult, your brain doesn't just stop growing, it actually forms new connections all the time. We know that when you're learning something you have new connections made. So, the brain is constantly growing and constantly changing."
Firestein was interested in how this growth occurs, and more specifically, how nerve cells, or neurons, grow new connections, which resemble branches on a tree.These branches, called dendrites, send and receive signals, and their growth is important to normal brain function; the more branches there are, the more sites by which a neuron can send and receive information.
image: Bonnie Firestein
By isolating and studying neurons in test tubes, Firestein and her colleagues found that a certain protein called cypin controls how the cells grow branches. The more cypin present in the cell, the more branches that cell grows, at least in the lab. Cypin appears to act as a "glue" that cements molecules together into long chains that form the "skeleton" of the dendrite. When the researchers removed cypin from neurons, they found that the number of branches on the cells decreased dramatically.
This observation provides a peek into what might be going in inside the brain. "We think that when you're learning something, for example, cypin might direct more branches," says Firestein. "And we know that, at least in a culture in a dish, if you make the nerve cells active, you actually see more cypin. We also know that if you make the cells more active, you see more branches. So maybe this is what is going on in the brain. When you're learning, you're making the nerve cells active, you're having increases in cypin, and then you're having more branches or more wiring, so that you can learn."
Just as the presence of cypin is associated with proper learning and memory, a lack of cypin is associated with learning and memory disabilities and diseases. "We know that in disease states such as Alzheimer's disease, Rhett's syndrome, fetal alcoholism syndrome, mental retardation, where there are deficits in memory, there are smaller amounts of branches on these neurons or these nerve cells," says Firestein.
Firestein says her data are in the preliminary stages right now, but "our ultimate goal is somehow to develop therapies or agents that either increase the amount of cypin or increase its activity, so that now you could have an increase in branches on the nerve cell, so that somehow you could restore, potentially, memory or learning."