Friday, February 6, 2015

Where am I? The puzzle of how spatial literacy works

Image above: Solving the issue of spatial memory and orientation. Our internal GPS and compass!

Related links to Spatialworlds
GeogSplace (a teaching blog for Year 12 geography)
Spatialworlds website

Australian Geography Teachers' Association website

Where am I??

Adelaide, Australia: S: 34º 55' E: 138º 36'

"The sense of place and the ability to navigate are fundamental to our existence. The sense of place gives a perception of position in the environment. During navigation, it is interlinked with a sense of distance that is based on motion and knowledge of previous positions.

Questions about place and navigation have engaged philosophers and scientists for a long time."

Have you ever wondered, How do we know where we are? How can we find the way from one place to another? And how can we store this information in such a way that we can immediately find the way the next time we trace the same path? These questions of spatial literacy have certainly fascinated me as a geography teacher and spatial technology user over the years and was the basis of my Churchill trip in 2007. Unfortunately I did not find as many answers to these questions as I would have liked during that experience.

 In cognitive psychology and neuroscience, spatial memory is the part of memory responsible for recording information about one's environment and its spatial orientation.

There is a long history of scientists and philosophers trying to unravel the question of spatial memory (we tend to relate to the term spatial literacy). More than 200 years ago, the German philosopher Immanuel Kant argued that some mental abilities exist as a prior knowledge, independent of experience. He considered the concept of space as an inbuilt principle of the mind, one through which the world is and must be perceived. With the advent of behavioural psychology in the mid-20th century, these questions could be addressed experimentally. When Edward Tolman examined rats moving through labyrinths, he found that they could learn how to navigate, and proposed that a "cognitive map" formed in the brain allowed them to find their way. But questions still lingered - how would such a map be represented in the brain?

Well, maybe we are on the verge of understanding the variance of spatial literacy between individuals and finally answering these questions.That is, why can some people navigate their world effortless and rarely need directions and maps (or their Google maps/GPS), whilst others are continually lost and have no idea of their orientation or the route they need to take or have taken?  For many years scientist have been working at explaining through neuroscience the answers to the question of the variance of spatial literacy between individuals.

In 2014 the Nobel Prize in Physiology or Medicine was jointly awarded to John O'KeefeMay-Britt Moser and Edvard Moser for their discoveries of cells that constitute a positioning system in the brain. These amazing scientist claim to have discovered a positioning system, an "inner GPS" in the brain that makes it possible to orient ourselves in space, demonstrating a cellular basis for higher cognitive function.

The location of the hippocampus

Place cells! 

In 1971, John O'Keefe discovered that a type of nerve cell in an area of the brain called the hippocampus was always activated when a rat was at a certain place in a room. Other nerve cells were activated when the rat was at other places. O'Keefe concluded that these "place cells" formed a map of the room - they were not merely registering visual input, but were building up an inner map of the environment. 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 could be stored as a specific combination of place cell activities in the hippocampus.

 The hippocampus

Grid cells!

More than three decades later, in 2005, May-Britt Moser and Edvard Moser furthered O'Keefe's work by identifying another type of nerve cell, which they called "grid cells", that generate a coordinate system and allow for precise positioning and pathfinding. Their subsequent research showed how place and grid cells make it possible to determine position and to navigate. May-Britt and Edvard Moser were mapping the connections to the hippocampus in rats moving in a room when they discovered an astonishing pattern of activity in a nearby part of the brain called the entorhinal cortex. Here, certain cells were activated when the rat passed multiple locations arranged in a hexagonal grid. 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. Together with other cells of the entorhinal cortex that recognize the direction of the head and the border of the room, they form circuits with the place cells in the hippocampus. This circuitry constitutes a comprehensive positioning system, an inner GPS, in the brain.

Grid cells derive their name from the fact that connecting the centers of their firing fields gives a triangular grid.

It is concluded  that place and grid cells exist in humans since the hippocampus and entorhinal cortex are found to be frequently affected in Alzheimer's patients at an early stage, and these individuals often lose their way and cannot recognize the environment. Knowledge about the brain's positioning system may, therefore, help us understand the mechanism underpinning the devastating spatial memory loss that affects people with this disease.

We have always known that we are not all alike in our ability to locate place and navigate our world, now we have the scientific theory to explain the phenomena of spatial literacy. Not sure how it helps us to teach geography but gee, it is interesting to know why some students just get spatial thinking and others struggle. What I am not doing in this posting in relation to this research is highlighting in any detail the oft-quoted differences between male and female spatial memory. However I found the following neuroscience summation from the Noble Prize winners research of interest and maybe a basis for a future (contentious) posting on the differences between male and female spatial memory/literacy.

"When it comes to performing activities that require spatial skills, like navigating directions, men generally do better. Women use the cerebral cortex for solving problems that require navigational skills. Men use an entirely different area, mainly the left hippocampus -- a nucleus deep inside the brain that's not activated in the women's brains during navigational tasks, the hippocampus, automatically codes where you are in space. As a result, women are more likely to rely on landmark cues: they might suggest you turn at the 7-11 and make a right at the church, whereas men are more likely to navigate via depth reckoning -- go east, then west, etc." 

Thanks to Rachel Crees from SSSI SA for these links and also the following fascinating podcast about recent science that's helping unlock how our brains make maps from moment to moment

1 comment:

Ivonne van Eerd said...

Interesting article especially the difference in navigation skills between men and women!