Connection between navigation, object location, & autobiographical memory

January, 2010

The existence of specialized neurons involved in spatial memory has now been found in humans, and appear to also help with object location and autobiographical memory.

Rodent studies have demonstrated the existence of specialized neurons involved in spatial memory. These ‘grid cells’ represent where an animal is located within its environment, firing in patterns that show up as geometrically regular, triangular grids when plotted on a map of a navigated surface. Now for the first time, evidence for these cells has been found in humans. Moreover, those with the clearest signs of grid cells performed best in a virtual reality spatial memory task, suggesting that the grid cells help us to remember the locations of objects. These cells, located particularly in the entorhinal cortex, are also critical for autobiographical memory, and are amongst the first to be affected by Alzheimer's disease, perhaps explaining why getting lost is one of the most common early symptoms.

Reference:

[378] Doeller, C. F., Barry C., & Burgess N.
(2010). Evidence for grid cells in a human memory network.
Nature. 463(7281), 657 - 661.

Source:

http://www.eurekalert.org/pub_releases/2010-01/ucl-thb012010.php

Topics:

How memory works

tags development:

seniors

tags memworks:

Sense of direction may be innate

July, 2010

A finding that navigational and spatial neurons are already tuned in newborn rats lends weight to the theory that a pre-wired spatial framework may provide a conceptual framework for experience in humans.

A rat study reveals that, for rats at least, an understanding of place and a sense of direction appears within two weeks of being born, seemingly independently of any experience of the world. The directional signal, which allows the animal to know which way it is facing, is already at adult levels as soon as it can be measured in newborn rats. Sense of place is also present early, but improves with age. Representations of distance appear a few days later. These processes depend on specialized cells in the hippocampus, which in humans plays a crucial role in long-term memory for events as well as spatial navigation. The findings fit in with the theory that a pre-wired spatial framework may provide a conceptual framework for experience.