I recently had a client comment on my lack of enthusiasm for using a GPS device while driving. Instead, I suggest drawing schematic routes to your destination including major landmarks. She asked why I felt this way, as she uses her GPS regularly and does fine. The answer is complex. There are so many forms of technology that clearly help us function in everyday life. Smart phones, computers, and GPS devices add convenience and help us overcome limits.

But there is a downside. These aids can also make us less aware of what’s around us. Christopher Chabris and Daniel Simons discuss the issue in their book, The Invisible Gorilla. They describe “inattentional blindness” as the trade-off of being so good at focused attention that we see far less than we think we do. Our brains as so good at focusing that we only see what we are prepared to see. As we drive, we focus on the presence of other cars and traffic controls and we miss two wheeled vehicles and pedestrians that are in plain sight. Once on my way to classes while in graduate school, I was hit by a panel truck turning right. They didn’t see me right next to them because they focused their attention on making the turn to their shop.

The problem is that it is hard to look for multiple things at once. As a rule, our brains are built to efficiently do one main task at a time. Simultaneous processing of information leads us to miss the unexpected and adds to the time it takes to act such as to move your foot to the brake. The small amount of time for multitasking in a car can mean the difference between life and death or injury.

Take for example the use of a cell phone while driving. Most of the time, using the cell phone doesn’t cause an accident. Therefore, we become confident that we can drive and talk at the same time. Studies show that subjects missed an unexpected object 90% of the time while talking on a cell phone. And it doesn’t matter whether it is a hand held or a hands free cell phone. It is not the nature of the phone that is the problem it is the limits of attention. The phone draws us somewhere else.

Back to the GPS. The in-car navigational systems do help us find our way but they can also lead us to drive without noticing where we are going. There are examples of drivers using a GPS and driving onto a railroad track without noticing. A British truck driver who wedged his truck in a tight street provides another example. It took him three days to get out of the truck. Finally, there are the drivers who were using their GPS to find their way past warning signs of road closure and into the Avon River.

I am all for technology. But we must respect its limits as well as its advantages. For those with failing memory and cognitive skills, it is better just to drive. Driving familiar routes and driving only in the day may be the best solution for them.