Speed Cells Discovered In Rat Brains

Posted: Jul 16 2015, 4:30am CDT | by , in News | Latest Science News


Speed Cells Discovered in Rat Brains
A rat resting in a flower-pot in the Mosers' lab. Credit: Geir Mogen/NTNU
  • Speedometer Neurons Found in the Cerebral Matter of Rodents

Specialized speed cells have been found in the cerebral matter of rodents. And they happen to be a key feature of their navigation capabilities.

The speedometer complex has been discovered in the grey matter of rats. When the rodents move at the speed of light, the neurons fire incessantly and when they scuttle along at slower speeds, the neurons seem to fire in a more sluggish fashion.

These special cells are part and parcel of the navigation system of the rat’s neurology. They help rats record where they are at present and where they have been in the past. 

A seven year study in Norway found this specialized neurological system deep within the brains of rats. The Nobel Laureates who conducted the research project found to their surprise that rats possessed a GPS system that was way more sophisticated than our modern technological contraptions found in cars.

There are “place cells” which show activity in response to a particular area where the rat is stationary or moving. Then there are certain alternative neurons which fire in accordance with barriers the rats chance upon. They also respond to changes in the direction of the skull of the rat. 

By the way, “place cells” were found for the first time in the 70s. But we have come a long way since. Today we know that data is collated from all these variegated cells and sent to the main hub in the brain which then forms a picture of the locale within the subterranean tunnels. Speed cells are necessary since they let the internal map be renewed time after time.

In the recent experiment, many rats had electrodes affixed within their brains. These electrodes penetrated the cortical region of the brain where the grid cells are located. And the signals came loud and clear on the instruments the scientists were employing to get at the data. 

“Weak speed signals had been seen in the brain, but this new class of cells give us a clear, powerful signal,” says Nachum Ulanovsky of the Weizmann Institute of Science in Rehovat, Israel, who studies navigation neurons in bats.

“The difference is like the speedometer in your car measuring 50 m.p.h. quite accurately — rather than with a plus or minus error of 40 m.p.h..” Researchers currently assume that neural navigation systems are fairly similar across mammals, although it would be difficult to look for the speed cells in humans.”

“Whether the navigation picture is complete is another matter,” says Edvard Moser. Other, as-yet undiscovered, cell types may turn out to be important, he says, as might the interactions between all of the various navigation cells.

“The next step is to understand how the different cell types work together to produce a sense of location — and how the map is used for navigation.”

Basically, in the experiment, the rats were fitted into vehicle-like structures that ran on rails and had a reward of chocolate pellets at the end. As the rats moved along in search of the treat, the scientists noted down the activity in their neurons.

Rats were also allowed to roam freely and go after pellets of food as the researchers gained evidence regarding the rate of firing their neurons underwent. Over a long period of time, it was found that 15% of the cells were speed cells.

These cells showed weak signals when the rats were stationary and went into overdrive when the rats raced along their paths. Clues into the cortical navigation systems of rats may later on lead to advanced research into the way humans find their directions on a daily basis. 

You May Like


The Author

<a href="/latest_stories/all/all/20" rel="author">Sumayah Aamir</a>
Sumayah Aamir (Google+) has deep experience in analyzing the latest trends.




Leave a Comment

Share this Story

Follow Us
Follow I4U News on Twitter
Follow I4U News on Facebook

You Also Like


Read the Latest from I4U News