Why Is Navigation Crucial? Because It's the Same as Memory
One area of the brain navigates not just where we are but what we remember
Posted Apr 15, 2016
Sucks for everybody, that the smartphones and other GPS-enabled devices we use to navigate for us can lead to deterioration of the navigation centers in our brain. (How this happens was outlined in the previous post.)
Given the importance of navigation to all life, atrophy of our navigation centers is bad enough. The fact that such atrophy might well lead, down the road, to diseases such as Alzheimer’s and dementia boosts the problem to a whole other level of gravity.
But something else is absolutely crucial to consider when examining these issues, and that is the following: Our brain’s navigation centers are, to a large extent, identically equal to our memory centers.
That the hippocampal formation, or HCF—a complex of organs clustered in the brain’s center—is profoundly associated with memory has been known for some time, but every day brings further evidence of how crucial the HCF’s role is in the memory process. Experimental proof can be negative: trauma to parts of the hippocampal formation reliably leads to severe amnesia—as well as positive; functional MRI images indicate heavy activity in the HCF when memory tasks are assigned. All in all, the fact that the hippocampal formation not only allows us to navigate streets, waterways, and our apartments, but also our short-, medium- and long-term memories, is pretty much accepted in the scientific community.
According to researchers, the HCF works as a kind of routing center for what we remember, sending memories to be stored in other parts of the brain, in particular the “conscious,” prefrontal lobes; keeping track of where those memories are located; and retrieving them when triggered.
Thus, when someone says “motorcycle” to me, my HCF instantly hooks up with the new Triumph 900-cc Bonneville Street Twin motorcycle I’d like to own, which I saw last week on the street in the West Village; with my friend Dan, in South Yarmouth, Mass., who first told me about it; with Dan’s road bike, that he showed me nested in its small garage, the 6-volt battery on trickle-charge; with the trickle-charge I should be administering to my boat’s batteries but am not; with the garage in Massachusetts where my own 6-volt charger sits idle; with all the damn junk from various family moves that has accumulated in that garage; with my brother, whose junk a lot of this is, and with whom, in our twenties, I shared ownership of a Yamaha dirt-bike; with feelings of guilt and helplessness associated with my inability to clean the garage out; with other triggers for guilt and helplessness (having been raised catholic, there’s no shortage); and so on ad infinitum, until another memory sparks a different cascade of associations.
Dr. Eleanor Maguire, a University College London researcher and leading expert in the field, told me that she believes one reason memory and navigation are associated lies in the deeply spatial basis of our memory system—the fact that, whether we’re conscious of it or not, most of the events and people we remember are linked to the actual places we met or experienced them.
We are our personality, our personality is what we remember. It follows that the navigation centers of our brain determine who we are. We neglect those centers at our peril. (Next post: How the Internet has created a new kind of mental navigation)