Archive

Posts Tagged ‘Neurogenetics’

Discovery of Gatekeeper Nerve Cells Explains the Effect of Nicotine on Learning and Memory

December 16, 2012 Leave a comment

Swedish researchers at Uppsala University have, together with Brazilian collaborators, discovered a new group of nerve cells that regulate processes of learning and memory. These cells act as gatekeepers and carry a receptor for nicotine, which can help 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 study is published today in Nature Neuroscience.

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. Read more…

Advertisements

Researchers Show that Memories Reside in Specific Brain Cells

December 16, 2012 Leave a comment

Simply activating a tiny number of neurons can conjure an entire memory.

Our fond or fearful memories — that first kiss or a bump in the night — leave memory traces that we may conjure up in the remembrance of things past, complete with time, place and all the sensations of the experience. Neuroscientists call these traces memory engrams.

But are engrams conceptual, or are they a physical network of neurons in the brain? In a new MIT study, researchers used optogenetics to show that memories really do reside in very specific brain cells, and that simply activating a tiny fraction of brain cells can recall an entire memory — explaining, for example, how Marcel Proust could recapitulate his childhood from the aroma of a once-beloved madeleine cookie.

“We demonstrate that behavior based on high-level cognition, such as the expression of a specific memory, can be generated in a mammal by highly specific physical activation of a specific small subpopulation of brain cells, in this case by light,” says Susumu Tonegawa, the Picower Professor of Biology and Neuroscience at MIT and lead author of the study reported online today in the journal Nature. “This is the rigorously designed 21st-century test of Canadian neurosurgeon Wilder Penfield’s early-1900s accidental observation suggesting that mind is based on matter.” Read more…