Today, we're beginning to rely more and more on GPS and mobile phone-based applications to find driving directions. You might have seen ads on TV of young people so intently gazing at their phones that they have no sense of their immediate surroundings. While the creators of the ad may think it funny, there are real life tragedies, in which people may be victims of serious accidents.
We probably stop less to ask passers by the way. We might trust the road enough to make the mistakes I did. And if everyone was trusting their GPS devices as much as I did, sleepy villages would suddenly face a huge rush of traffic. Like this British village did. We could also end up taking paths that are prohibited. For while on the map it may be the shortest distance, in reality it may be a one way we cannot travel on.
But these are all matters that could be solved by being a bit more careful. By stopping to ask the locals. By reading the road signs. In London, all taxi drivers must pass a test known as 'the knowledge', in which they must know by memory every lane and by-lane in that city! In fact, scans of their brains showed that London taxi drivers had bigger hippocampuses - the part of the brain responsible for spatial memory. But now, even they are beginning to rely on GPS to drive around the city.
On June 6th, the Washington Post reported that excessive use of GPS may actually be affecting our brains. As we rely too much on spoon-fed instructions from mechanical devices, we might face the risk that our hippocampuses might begin to atrophy. Is that really likely?
Earlier this year, neuroscientists Giuseppe Iaria, Jason Barton and others described a new illness of the hippocampus - 'developmental topographical disorientation' (DTD). Persons who naturally suffer from DTD have great difficulty forming 'cognitive maps', the pictures in their brain that help them find their way in the real world. This is because their hippocampuses are not forming new memories when they encounter a new place. In fact, they could even get lost in places they have known for years. Could we be on our way to getting DTD, with our reliance on GPS devices?
There are two ways we form our spatial memories. One is by making associations between landmarks (like my house is between the theatre and the sweet shop). These are our cognitive maps. The other way is by creating mental instructions, which help us while we are moving. For example, 'get off the bus at the stop after the tall white building'). These are in some sense, our mental driving directions.
Now the brain has an efficient but cruel way to operate. Those neural pathways that are used again and again are 'reinforced', i.e. supplied with more nutrients. That's why something that we found complicated at the beginning can become so easy, we don't realise how difficult it was to learn it at first (think of cycling or swimming). Conversely, those parts of the brain used less or not at all are starved, till the nerve cells die. Which is why those of us who are not maths teachers will have forgotten our trigonometry formulas. The more we cede the job of making these maps and directions to our GPS devices, the less work our hippocampus does. And that creates the risk that we might lose our spatial memories faster than we expect.
If you think you're already facing such problems, you can take a test here. This test was designed by the discoverers of DTD.