We drive on the left-hand side of the road in Mauritius. Hence, as driver you sit on the right in the car. The gearbox, which you operate with your left hand, has the same “double H” schema as in right-hand side driving Europe, with the first gear on the usual most left, top position of that “double H”, that is, away from you, which requires some short adaptation. The turn-signal is at your right hand, the windscreen wipers at your left – which is swapped compared to Switzerland. So, there’s some windscreen wiping in lieu of the turn signal in the beginning…
In general, the basic adaptation is quick. It becomes natural again towards which side to look to check for incoming traffic, and you never go down the wrong way. Unnecessary windscreen wiping is replaced by actually signalling. And so on.
However, I realised that sometimes it takes me longer to act correctly. Especially in more complex and dynamic situations, I seem to need to actually think consciously about my perceptions and the related needed actions. In Europe, when driving on the right side of the road, driving does not really need conscious thinking anymore. After decades, all is pretty much hard-wired, unconscious.
Why does it change, only because I drive on the left side? When you consider that our brain is – at its basic level of “doing things” – a very capable pattern-learning, pattern-matching (perceptions) and pattern-triggering (actions) apparatus, things become clearer: the perception patterns are pretty different now! Hence, my brain needs to memorise and to rewire the patterns anew, in other words, I need to learn stuff again. The perception patterns must again be processed by conscious thinking, before they are learned and the matching and triggering of patterns is “pushed down” to less abstract and less conscious, but more specific and automated levels.
PS: yes, the action patterns also need some adaptation – see the windscreen wiper problem above –, but there’s less fundamental change and thus quicker adjustment.
PPS: note that I leave all the complex pattern building and handling in the brain related to emotions, desire, impulsivity, etc. – as described here, for example – out of the picture here, I only talk about the simple task of driving my car in traffic!