In a recent paper in the journal Science, scientists have developed a way to record the electrical activity of a single animal using radio-frequency identification chips.
The method uses an infrared sensor that emits infrared light.
The chip emits a radio frequency, which can be picked up by the animal’s hearing, nose and eyes, and can be used to track its movement.
The result is a picture of the animal with its movements recorded.
“The sensor has a very wide field of view and the sensitivity is very high,” says study co-author Michael Toth, a physicist at the University of Michigan.
The team found that when an animal moved at a given speed, it was recording electrical signals in its brain.
“You can track the brain activity from a moving animal,” Toth says.
This approach works well in a lab setting where the animals have little room to move, but it’s not ideal for field experiments.
To create a more natural environment for the experiment, the team recorded the animal from a distance of two meters.
The images are stored on an infrared chip in a computer, and the scientists used the chip to record each animal’s brain activity for the next six months.
During that time, the chip captured more than a million brain waves, a large number for such a small animal.
“There was no indication the chip had picked up anything,” says co-lead author Thomas S. Hultman, a biologist at the Massachusetts Institute of Technology.
“It’s a little bit of a surprise because we had anticipated that it would.”
The chip recorded about 15 milliseconds of activity per animal, a relatively small amount for such an active animal.
But when the researchers took the chip out of the lab and put it on a treadmill to test its effectiveness, the amount of activity recorded by the chip jumped to 20 milliseconds per animal.
That’s a large amount of data for a small mammal.
“This is the first time that we’ve recorded neural activity of any animal with this technology,” Hultmann says.
The researchers have used this technology to study how the brain processes information.
“These are not things that happen in a video game,” Hultsman says.
“They’re very powerful tools that we use to study animal behavior.”
The results are published in the April 16 issue of Science.
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