Sat-Nav is the most popular of boy's toys, but, say the Royal Geographical society, they're bad for our brains. Good old-fashioned map-reading skills are being lost at a time when they were never more needed, both physically and metaphorically.

"I firmly believe that our Sat-Navs are depriving us of our ability to read maps. This is a terrible thing because maps are more than pieces of paper that tell us how to get from A to B. They can have so much extra than can benefit us, " says Dr Rita Gardner, president of the Royal Geographical Society.

Map reading, it seems, helps root both our outer selves and our inner souls. According to Dr Gardner's theory, map-reading skills are vital because they teach us, in hippyspeak, to find where we're at both physically and socially within a spatial setting.

Drivers who use Sat-Navs may think that it's the easy way to get from A to B, but if all they do is follow a disembodied voice, they miss out on everything around them, impoverishing the sum of their knowledge.

The ability . . . just to take a random example . . . to follow a map of the roads with numbers for names around the new Dundrum town centre is not just a matter of getting there, it's a learning process about the changing face of Ireland.

And so, on a journey to Dundrum, we take in information about our habitat and habits from the rows of shiny new apartment blocks with their strangely angled roofscapes and richly-vowelled names. We learn from the oversize gyms designed to turn us into size 00s that dot the new roadscape and of course, when the towering vision of our destination . . . the town centre itself . . . hoves into view, we can only gasp in wonder at this cathedral of our new religion:

consumerism.

All of this, of course, we can analyse at our leisure . . .

parked in the traffic jam that extends almost to that other long and winding road to nowhere, the M50.

And for those whose map-reading abilities are less than perfect, we will, says Dr Gardner, also have sharpened our hunter instincts and our sense of discovery as we circle yet another roundabout for the third time, trying excitedly to read the signs that point to the right exit.

The metaphors for life on a journey like this are endless.

By contrast, tales of Sat-Nav-led short hops taking hours thanks to detours to lake shores and up steep boreens to mountaintop cul-de-sacs are legion.

But in this world where everything changes so fast it's hard to stand still, isn't it nice, just sometimes, to take a rest . . . to turn on, pre-programme . . . and be led, brainless and unquestioning, by the nose?