Gatekeeper nerve cells explain effect of nicotine on learning and memory

October 8, 2012 | Science / Technology | Written by

London, October 8: In a new study, researchers have discovered a new group of nerve cells that regulate processes of learning and memory.

These cells, which have been discovered by Swedish researchers at Uppsala University together with Brazilian collaborators, act as gatekeepers and carry a receptor for nicotine that can explain our ability to remember and sort information.

The discovery of the gatekeeper cells, which are part of a memory network together with several other nerve cells in the hippocampus, reveal new fundamental knowledge about learning and memory.

The hippocampus is an area of the brain that is important for consolidation of information into memories and helps us to learn new things. The newly discovered gatekeeper nerve cells, also called OLM-alpha2 cells, provide an explanation to how the flow of information is controlled in the hippocampus.

“It is known that nicotine improves cognitive processes including learning and memory, but this is the first time that an identified nerve cell population is linked to the effects of nicotine,” Professor Klas Kullander at Scilifelab and Uppsala University said.

Humans think, learn and memorize with the help of nerve cells sending signals between each other.

Some nerve cells send signals far away to other areas of the brain, while other neurons send signals within the same area. Local nerve circuits in the hippocampus process impressions and turn some of them into memories.

The new research study literally sheds new light on the intriguing mechanism of how does this work and how can nicotine improve this mechanism.

“We have used a new technology called optogenetics, in which light is used to stimulate selected nerve cells. We were amazed when we discovered that light activation of the gatekeeper cells alters the flow of information in the hippocampus in the same way as nicotine does,” co-author Richardson Leao said.

Through research on mice, the scientists showed that the gatekeeper cells connect to the principal cell of the hippocampus. Active gatekeeper cells prioritize local circuit signals arriving to the principal cell, while inactive gatekeeper cells allow inputs from long-distance targets.

Nicotine activates the gatekeeper cell, thereby prioritizing the formation of memories via local inputs.

The study has been recently published in Nature Neuroscience. (ANI)