If you were not aware, the Nobel Prize in Physiology or Medicine was awarded to three recipients this past October. You would be quite right in saying that this piece here is a few months removed from the news. Nevertheless, the information contained within the scientists’ findings are as important today as they were last year, and they will continue to have influence for years to come.
On Oct. 06, the The Nobel Assembly at Karolinska Institutet awarded the prize as half to John O’Keefe and the as half, but jointly, to May-Britt and Edvard I. Moser. It was back in 1971 when the O’Keefe discovered “place cells” in rat brains that were markers which helped create the map of a room. This left multiple questions unanswered — such as how the brain navigated a room — and it was not until 2005 when May-Britt Moser and Edvard Moser discovered “grid cells” which helped complete the puzzle.
In order to understand exactly how these types of cells work together, it is first necessary to understand what they do apart from one another and where they are located in the brain. The Nobel Assembly’s press release first describes how place cells act:
“O’Keefe concluded that the hippocampus generates numerous maps, represented by the collective activity of place cells that are activated in different environments. Therefore, the memory of an environment can be stored as a specific combination of place cell activities in the hippocampus.”
It then goes on to describe the activity of grid cells:
“Here, certain cells were activated when the rat passed multiple locations arranged in a hexagonal grid,” the press release states. “Each of these cells was activated in a unique spatial pattern and collectively these ‘grid cells’ constitute a coordinate system that allows for spatial navigation.”
Further inspection of the text reveals that the grid cells, which exist in the entorhinal cortex, work with other cells in the cortex to determine the direction of the head and the borders of a room. From there, the cells within the entorhinal cortex communicate with the place cells in the hippocampus. Those connections create the entirety of the brain’s internal positioning and navigation system.
Although the researchers’ original studies determined these findings by studying the brains of rats, there have been additional studies completed with advanced brain imaging techniques and also within scenarios where patients are undergoing brain surgery. Those studies concluded that the place cells and grid cells also exist in human brains.
The Nobel Assembly awarded these individuals not just for their initial findings. The existence of place cells and grid cells means more than just the existence of an internal navigational system within humans; it also suggests that high-level functions in the brain can take advantage of specialized cells that communicate with one another across different parts of the brain. There are implications here for deeper understanding of how humans process all manner of information, how we store information, and how different types of cells make it possible for our brains to do the things we do.
Despite the relative simplicity provided in this text, the researchers’ findings are, at least to this writer, fascinating and mind boggling. If nothing else, I am floored by my brain’s ability to complete high-level tasks with ease. There is an untold number of connections taking place with every word I type and with every thought that comes to mind. It is amazing that anything coherent comes onto the page at all.
Image courtesy of ActiveDendrite via Wikimedia Commons