Lab rats can be taught to do just about any simple task for food or a treat.
Scientists can also watch what is going on inside a rat’s brain by inserting a few electrodes. So it's not unusual that researchers at the University of Pittsburgh attached wires to the brains of a group of rats while performing menial tasks. The researchers wanted to understand the effect of anxiety, but what they learned was unusual.
The test went like this: one of three holes in the wall of the rat’s cage would light up; if they put their nose in the hole with the light, a treat would drop into the other side of the cage. But just when the rat got used to the idea, the rules would change and they would have to ignore the light and begin using either the right or left hole exclusively.
“Rats are pretty smart and they could figure this out and they could four or five shifts during a recording session,” said Rita Moghaddam, University of Pittsburgh professor of neuroscience.
Once the rats were trained, they were given a drug that induced mild anxiety and they did not perform as well.
“Their decisions were not optimal, they made more mistakes and they took longer to decide which was the optimal choice,” Moghaddam said.
Though their poor performance might not have been surprising, the reason why they did not perform well was a surprise.
“We found that anxiety essentially numbs the activity of some of the neurons in this area of the brain called the prefrontal cortex during decision making,” Moghaddam said.
That was the exact opposite of what they expected.
“Your brain feels like it’s on fire, so (we thought) maybe it’s over activation, too much noise,” Moghaddam said. “But essentially we found that with this part of the brain, it’s not being activated sufficiently to allow you to make the right choice.”
The research is still preliminary. Moghaddam and her students said they hope to begin looking at other parts of the brain and the differences between male and female rats. But she said, in the meantime, there are ways to use this information.
Many of the current pharmaceutical treatments for anxiety have undesirable side effects and some are addictive, which has lead to more research toward finding new drugs, as well as improving cognitive and behavioral therapies.
“This particular model provides a very reliable way of measuring anxiety and measuring what it does to the brain system," Moghaddam said. "So, if there are novel treatments we can actually go to this model as opposed to some of the older models in order to test the treatment."
The research was published in The Journal of Neuroscience.
In this week's Tech Headlines:
- Tech workers at Pittsburgh-based PNC Financial Group spent two days last week in an internal hack-a-thon aimed at creating new apps that can help both internal and external processes. The Pittsburgh Business Times reports 38 teams from Pittsburgh, Cleveland and Columbus each came up with their own ideas. PNC Chief Enterprise Architect Eric Donnelly said the hope share with customers the best ideas.
- Microsoft has filed a suit against the Justice Department over its use of court orders requiring the company to turn over customer files stored in its computer centers. The company said the government is using an outdated 1986 law to get court orders for customers' data, while in some cases prohibiting the company from notifying the customer. Microsoft said the orders violate its constitutional right to free speech, as well as its customers' protection against unreasonable searches.
The Associated Press contributed to this report.
