I first learned of place cells and the work of neuroscientists to locate sense of place in the brain from an article published in the New Scientist in 2006 (John Zeisel, “A Sense of Place,” New Scientist 4 March 2006, 50-51). My initial reaction was that this was scientific reduction, taking something remarkably subtle and complex and explaining it in terms of a physiological mechanism. I became less dismissive when I discovered that this research was in part an attempt to find a underlying cause for Alzheimer’s, in which a sense of place (in the fundamental meaning of knowing where you are and how you got here) is one of the first faculties to drift away, and there is some indication that damage to place cells could be a cause. And as I have learned more I have come increasingly to think that the research of neuroscientists provides valuable insights that complement rather than undermine phenomenological thought about place.

There are growing indications that “place cells” and “grid cells” – the neurons in our brains that react to specific locations – play key roles in our experiences of places. The three key scientists involved in the discovery of these cells – John O’Keefe, and Edvard and May-Britt Moser – were awarded the Nobel Prize in the Physiology of Medicine in 2014, and the nomination stated that: “The sense of place and the ability to navigate are some of the most fundamental brain functions. Sense of place provides a perception of the position of the body in the environment and in relation to surrounding objects.” Furthermore it is linked to experiences of distance and direction, and to memory.

Diagrams recording place cell firing and grid cell firing in respective parts of the brain. Yellow indicates no firing of an electrode, other colors fire when the animal was in a particular part of the maze. The place cell patterns are unorganized and do not correspond to actual spatial patterns. Grid cell firings have a hexagonal pattern.

Place and Grid Cells
Place cells were identified and named by O’Keefe in 1971. He connected electrodes to the hippocampi of rats moving freely around mazes, and discovered that whenever a rat was in a certain part of the maze a particular neuron fired – each place in the maze apparently had its own neuron. Hence “place cells.” There was, however, no apparent correspondence between the patterns of place cells in the brain and the spatial relationships of actual places. This puzzle was resolved thirty years later when the Mosers identified what they called “grid cells” in the entorhinal cortex (a part of the brain adjacent to the hippocampus) which, in effect, organize the relationships of distance and direction between place cells. It has been suggested that together place and grid cells construct a sort of cognitive map of the world as we experience it.

The hexagonal pattern of grid cell firing. The grey, wavy line in the background shows the movement of a freely moving rat in an experimental cage. The firing pattern of grid cells is superimposed – locations at the intersections of the grid lines generated repeated firings to create the hexagonal patterns. 

[Two related notes:
1. Other related types of neurons related to spatial experience have been identified – such as head-direction cells and border or boundary cells – which also contribute to how place memories are stored in the brain.
2.Grid cells are remarkable not only for their apparent organizational role in brain activity, but also because their firing patterns seem to take the form of a hexagonal grid, strangely reminiscent of the patterns in what in Geography is known as Central Place Theory. I have no idea what to make of this.]

Memory
Place and grid cells are in parts of the brain known to play critical roles in memory. It has been established that their functions are related not only to remembering how to get from place to place but also to episodic memories – memories related to one’s own experiences. It has also been established that there is “plasticity” in these memories of places. In other words, even if some of the characteristics of a place are changed, such as colours, or heights of walls, or lighting, the same place cell continues to respond to it.

Place and Grid Cells in Humans
How is this known to happen in humans? Individuals having brain surgery for other reasons, such as treatment for acute epilepsy, and are therefore immobilized, have agreed to participate in experiments involving virtual reality. Their brain activity has been monitored as they navigate through a virtual city where they are asked to undertake tasks at specific locations, and then to recall aspects of those locations and tasks. Firing patterns in place and grid cells are consistent with those in laboratory animals.

Implications
What does this mean for understanding place and sense of place in what might be called the geographical world of home, neighbourhood, city, other countries?

Clearly place and grid cells have to be functioning well if we are to find our way around, whether it is from the living room to the kitchen and back again, or around the cities we live in. We know this because those suffering from Alzheimer’s lose that ability and it appears this may be related to atrophy or malfunction of place and grid cells. In effect, place and grid cells hold the memories, meanings and sense of places.

The relationship between places and episodic memories captured in a sign in store window in Victoria British Columbia

More philosophically, it appears there is a complex correspondence between what I perceive and experience in the geographical world and what goes on in my brain. If I understand the neuroscience research correctly, there is in my brain a neuron which somehow stores or is related to my memories for each place I have experienced, whether my kitchen, the house my grandfather built that I lived in fifty years ago for a few years, or the view of Florence from the other side of the Arno. This is a huge amount of information and it all has to be sorted and recalled easily if we are to find our way around and talk about where we grew up and went on vacation. May-Britt and Edvard Moser and David Rowland put it this way in their Cold Spring Harbor article: “Spatial memories place high demands on capacity. Memories must be distinct to be recalled without interference and encoding must be fast…for large quantities of uncorrelated spatial information.”

Given this, I think the cognitive map metaphor is too simple, not least because it assumes that place and grid cells function mostly as recording devices of places that exist in a real world. My interpretation is that research into place and grid cells is demonstrating the remarkable complexity and flexibility of place experience in which the relationship between the geographical world and place and grid cells is dynamic and two-directional, continually changing both as things in the world change and as memories are accumulated. Place and grid cells record our experiences of places as memories, and the memories stored in those cells continually inform our experiences of places. By extension, notions of an objective world that is separate from subjective experience seem to have no neurological substance. What goes on in our brains, and what goes on in the world those brains encounter are so profoundly interconnected that to separate them has to be considered equivalent to self-imposed dementia. Phenomenologists have always suspected as much.

Some References:
A substantial recent review of work on place, grid and related cells, by the Mosers who won the Nobel Prize and David Rowland, is available at Cold Spring Harbor Perspective in Biology at:
http://cshperspectives.cshlp.org/content/7/2/a021808.full

The connection between place and grid cells and Alzheimer’s is discussed at http://www.kavlifoundation.org/science-spotlights/understanding-our-sense-place#.VicTyKTWr3U

The following article from Frontiers in Systems Neuroscience discusses the link between place cells and episodic memory:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4148621/

Brain Facts discusses the evidence of place and grid cells in humans.
http://blog.brainfacts.org/2013/08/human-grid-cells/#.ViRyfaTWr3V

In the last couple of months I have read several articles that provide insights into the importance of place in the context of contemporary mobility. Some of these include survey and census information about how Americans relate to local areas and how many of them changed their place of residence in one year. This information is important because discussions about place mostly approach it in terms of particular, long-term local experiences, giving the impression that these are the norm. This may be the case for a small majority but it seems that a large minority of the population want to move elsewhere and every year several tens of millions act on this. Place experiences for them are of many places and multi-centred.

My interest was first aroused by an article in the Atlantic Monthly in March “Staying Close to Home , No Matter What,” which discusses the inclination of Americans not to move away from where they grew up. This is in fact a commentary on a recent poll in the Heartland Monitor that examined American’s experiences in their local areas, including their opinions on the local economy, businesses, and institutions.

“Place of Discovery”, a 1927 painting by the Bauhaus artist Paul Klee.

The Heartland Monitor poll (undertaken by Allstate/National Journal) asked 1000 people  whether their local area is best described as a small city or town (41%), a suburb (22%), a big city (19%)  or a rural area 17%); these are not perhaps what many might consider as local areas. Nevertheless, and regardless of what sort of local area they lived in or their demographic or socio-economic group, respondents rated their local area very positively in terms of its quality of life and environment, and higher than the country in terms of political leadership. Perhaps what is of special significance from the perspective of place is that 54% of the respondents lived in the area where they had grown up  (34% had never moved away while 19% had left and returned)., and almost half of those had lived in the same area for 21 or more years.

It was these percentages that led the author of the Atlantic Monthly article to interpret the Heartland Monitor poll as indicating that Americans generally like to stay put. Well, yes, strictly speaking the sample of 1000 is sufficient to make reasonably confident extrapolations for the American population as a whole, and to suggest that just over half the US population likes stays close to home, which is to say in the same city, town or suburb.  But it is important to put numbers to this. The U.S. population is about 320 million, so 54% means that roughly 170 million want to stay in their local area. On the other hand, about 150 million do not, so it seems almost half Americans are restless, and for them moving elsewhere is almost as big an attraction as staying put.

A U.S. Census report in March 2015 “Staying or Going” gives further details about staying close to home or moving elsewhere. It concludes from various data that about 10 per cent of Americans, (specifically 10 million households or about 35 million people) are dissatisfied with where they live and would like to move because of the poor quality of their housing or their neighborhood, or concerns about local safety and inadequate public services. The report indicates that while In 2010-11 only about 2 million of those dissatisfied households actually did move, another 11 million households moved for other, presumably more positive, reasons. While there is some evidence that residential satisfaction is increasing and rates of moving are declining, nevertheless about 35 million Americans move to a new place every year. In each decade that is the equivalent of the entire population of the United States moving to some other place in the country.

Multicentred place experiences conveyed in real estate signs in a suburban area of Toronto popular with Chinese immigrants, 2013

Another U.S. Census Report in March 2015 “Packing it Up” suggests that 1 in 9 people changed residences in 2013-2014 (in 1948 it was 1 in 5, so this has declined over the last 60 years).  Of the 35 million who moved, 23 million stayed in the same county, another 6.5 million moved to a different county in the same state, 1.2 million moved to a different state, 3.4 million moved to a different part of the U.S. and 1.1 million moved abroad. While this supports the general notion the most people prefer to stay close to home (in the same county or same state), it is nonetheless the case that in a single year 6.7 million Americans made substantial moves. To put it rather differently,at the county and state level there appears to be a constant place churning as people move to other neighborhoods or cities, while at the national level the equivalent of the population of Philadelphia or Dallas moves to another state or region each year. For some people place may be an enduring source of focused experiences, but clearly for many millions of families and individuals it is what Luch Lippard in her book The Lure of the Local refers to as multi-centred.

Multi-centred place experience is also common at an international scale. The “Packing it Up” report notes than 1.1 million Americans moved abroad in 2013-14. If this is sustained it amounts to 10 million in a decade, the equivalent of the population of Chicago – an American diaspora spread around the globe. This not exceptional. With the waves of mass migration that have occurred over the last 70 years there many diasporas have been created, possibly more than 250 million people who have allegiances to several places and counties. The article “Long-Distance Parenting” by Ana Santos in the March 2015 Atlantic Monthly examines aspects of the Filipino diaspora. A state-encouraged policy of labor migration was introduced by the Philippines in the 1970s as a way to deal with high levels of unemployment and there are now about 10 million Filipino migrant workers living in other countries. Many of these live away from home for years or decades. They maintain some connection with their children and families by sending remittances and also balikbayan boxes – gift packages filled with goods and presents. Even though they have strong allegiances to their place of origin their lives are multi-centred.

Highway as Place with a History. This mural is at Aurora and 105th in Seattle.

I do not regard with dismay these reports of a large proportion of the population either moving or wanting to move elsewhere.  I do not think they should be interpreted as evidence that millions of people are unplaced or disembedded.  Instead I think they reveal that place and place experiences has to be understood as more than lifelong or long-term dwelling somewhere.  For many people place experiences are by choice multi-centred, they consist of relatively short-term encounters.  Whether this makes them shallower or less authentic in some way is an open question, which I expect to explore in future posts.