(Continued from a
White Paper published by the National Safety Council, April 2012)
Multitasking is a myth. Human brains do not perform two tasks at the same time. Instead, the brain handles tasks sequentially, switching between one task and another. Brains can juggle tasks very rapidly, which leads us to erroneously believe we are doing two tasks at the same time. In reality, the brain is switching attention between tasks – performing only one task at a time.
In addition to “attention switching,” the brain engages in a constant process to deal with the information it receives:
1.Select the information the brain will attend to
2.Process the information
3.Encode,a stage that creates memory
4.Store the information.
Depending on the type of information, different neural pathways and different areas of the brain are engaged. Therefore, the brain must communicate across its pathways. Furthermore, the brain must go through two more cognitive functions before it can act on saved information. It must:
5.Retrieve stored information
6.Execute or act on the information.
When the brain is overloaded, all of these steps are affected. But people may not realize this challenge within their brains
The brain not only juggles tasks, it also juggles focus and attention. When people attempt to perform two cognitively complex tasks such as driving and talking on a phone, the brain shifts its focus (people develop “inattention blindness”) (page 9). Important information falls out of view and is not processed by the brain. For example, drivers may not see a red light. Because this is a process people are not aware of, it’s virtually impossible for people to realize they are mentally taking on too much. When we look at a view before us – whether we are in an office, restaurant or hospital, at the beach, or driving in a vehicle – we believe we are aware of everything in our surroundings. However, this is not the case. Very little information actually receives full analysis by our brains. Research shows we are blind to many changes that happen in scenery around us, unless we pay close and conscious attention to specific details, giving them full analysis to get transferred into our working memory.
Brain researchers have identified “reaction-time switching costs,” which is a measurable time when the brain is switching its attention and focus from one task to another. Research studying the impact of talking on cell phones while driving has identified slowed reaction time to potential hazards are tangible, measurable and risky (page 10). Longer reaction time is an outcome of the brain switching focus. This impacts driving performance.
The cost of switching could be a few tenths of a second per switch. When the brain switches repeatedly between tasks, these costs add up. Even small amounts of time spent switching can lead to significant risks from delayed reaction and braking time. For example, if a vehicle is traveling 40 mph, it goes 120 feet before stopping. This equals eight car lengths (an average car length is 15 feet). A fraction-of-a-second delay would make the car travel several additional car lengths. When a driver needs to react immediately, there is no margin for error.
Brains may face a “bottleneck” in which different regions of the brain must pull from a shared and limited resource for seemingly unrelated tasks, constraining the mental resources available for the tasks. Research has identified that even when different cognitive tasks draw on two different regions of the brain, we still can have performance problems when trying to do dual tasks at the same time. This may help explain why talking on cell phones could affect what a driver sees: two usually unrelated activities become interrelated when a person is behind the wheel. These tasks compete for our brain’s information processing resources. There are limits to our mental workload. The workload of information processing can bring risks when unexpected driving hazards arise.
Under most driving conditions, drivers are performing well-practiced, automatic driving tasks. For example, without thinking about it much, drivers slow down when they see yellow or red lights, and activate turn signals when intending to make a turn or lane change. These are automatic tasks for experienced drivers. Staying within a lane, noting the speed limit and navigation signs, and checking rear- and side-view mirrors also are automatic tasks for most experienced drivers. People can do these driving tasks safely with an average cognitive workload. During the vast majority of road trips, nothing bad happens, as it should be. But that also can lead people to feel a false sense of security or competency when driving. Drivers may believe they can safely multitask; however, a driver always must be prepared to respond to the unexpected.
. Would that be the best way to debate ??
. I did get a great laugh out of your reasoning and logic . Very interesting .
