Such knowledge is important because it provides clues as to how the far more complex human brain acts to alter behaviors, he said. One of the goals of his research at the Institute of Neuroscience at the University of Oregon is to understand the intricacies of brain signaling that allow people, such as athletes, to repeat and adjust tasks they perform repeatedly.
Cephalopods, which also include octopuses and squids, have 100 million nerve cells compared to the 10,000 in insects and the some one trillion in humans. "The idea is to look at simpler brains to allow us to generalize broad concepts that are applicable to humans," Tublitz said in an interview. "Much of what we've learned about the human brain at the cellular level has come from the study of invertebrates," he said.
His findings involving the European cuttlefish (Sepia officinalis) provide an example of system-level brain activity, he said in his presentation. Tublitz also discussed his lab's earlier findings involving cellular plasticity in the tobacco hornworm (Manduca sexta), also known as the hawk moth.
"We have identified a set of nerve cells in the moth whose properties are completely altered during metamorphosis," he said. "The biochemistry is altered. The translators that they use are altered. The shapes of the cells are altered, and their physiology is altered. The dogma is that most cells don't change their characteristics, but here's a case of nerve cells changing not only one characteristic but almost all of them."
The driving force of these changes is naturally occurring steroid hormones, he said.
Insects are fascinating because they accomplish complex behaviors with relatively few nerve cells. Moths, in particular, have easy-to-study nerve cells that are 10 to 20 times as large as those in humans, and they go through three distinct body states, each with its
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Contact: Jim Barlow
jebarlow@uoregon.edu
541-346-3481
University of Oregon
14-Aug-2006