Oriented!

January 3rd, 2015| Topic: RaMbLeS | 4

Your brain has a GPS! Yes, indeed! Two of them. Working in tandem.

One region in the brain, when travel is commenced, tracks the straight-line, as-the-crow-flies distance from A to B. The other, during travel, computes the precise, on-the-ground distance to get to B. The brain does both!

So declareth research funded by the Wellcome Trust and published in Current Biology: “A Goal Direction Signal in the Human Entorhinal/Subicular Region.”

Hugo Spiers and his team of scientists at University College London employed film footage to recreate the bustling streets of London’s Soho inside an MRI machine. Study subjects had to navigate their way through the winding district with all of its complex junctions and roundabouts, while their brain activities were being monitored: setting the course at the beginning of the journey, keeping track of the destination, making decisions at street junctions.

Said Spiers:

Our team developed a new strategy for testing navigation and found that the way our brain directs our navigation is more complex than we imagined, calculating two types of distance in separate areas of the brain. … The research is also a substantial step towards understanding how we use our brain in real world environments, of which we currently know very little.”

They discovered that brain activity in the entorhinal cortex (an area at in the brain, close to the nose) was essential for navigating the straight-line distance at the beginning of the journey. On the other hand, activity in another part of the brain, the precuneus (closer to the back of the head) was key to keeping track of the route while traveling.

Incidentally, these areas of the brain are among the first parts of the brain to be damaged in Alzheimer’s disease. Perhaps that’s why such patients easily get lost, even in their own homes.

Homing signals. In the brain!

And what was interesting was that the brain cells in the entorhinal cortex and the precuneus work differently. The ones in the former are sensitive to North, South, East, and West (a geocentric orientation). The ones in the latter are even more complex: they are egocentric in orientation, i.e., they tell one where the destination is, in light of one’s position is currently, as one travels: East of where I am, or South-West of where I am, or ….

Internal compass! Amazing!

Perhaps these hardwired orientations are part of the human situation. Navigating to a safe place, like home, is fundamental behavior for all complex animals.

But there is not just N, E, S, or W, towards which we have an inborn orientation. We also have a sense of the direction of true NORTH.

As Augustine (354–430) said:

You have formed us for Yourself, and our hearts are restless till they find rest in You.”

Or as Pascal (1623–1662) put it:

What else does this craving, and this helplessness, proclaim but that there was once in man a true happiness, of which all that now remains is the empty print and trace? This he tries in vain to fill with everything around him, … though none can help, since this infinite abyss can be filled only with an infinite and immutable object; in other words by God himself.”

An inbuilt God-shaped vacuum. Hardwired for true NORTH, Godwards.

Whom have I in heaven but You?
And besides You, I desire nothing on earth.
My flesh and my heart may fail,
But God is the strength of my heart and my portion forever.
Psalm 73:25–26

Amen. May He be our NORTH in 2015 and for the rest of our days.