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Attention: Definition and Examples

A man checking his phone while driving.What is attention?

Attention is the behavior a person uses to focus the senses, from sight to hearing and even smell. It may focus on information that matters outside of the cab (e.g., signals, traffic), inside the cab (e.g., displays, controls), or on the radio network. Attention to information that is not important is distraction.

Research shows that people have limited attention resources. This means we only have so much capacity to go around. We need to choose what to focus on that matters. For a train operator, focusing on what matters means paying attention to items of interest: the tracks, responding to signals along the route, observing orders, working together with the conductor, and more.

Without the ability to filter out unwanted information, the world would be chaotic. So we have to be selective in what we pay attention to. For instance, dividing attention across multiple tasks results in a loss in performance, which can contribute to incidents or accidents potentially costing loss of life and property.

Example of divided attention

Texting while operating a vehicle requires a driver to switch attention from one task to another. That impairs a driver's ability to focus on the task at hand, resulting in a slower reaction time.

Paying attention to what matters is important to avoid the costly consequences of an accident, whether operating a locomotive, driving a car, flying a plane, or crossing an intersection on foot.

Systems to Monitor Attention: Alerters

What are alerters?

Alerters are vigilance control devices (VCDs) installed in locomotive cabs, in addition to a dead man pedal, to manage drowsiness in locomotive engine crews. Based on engineer behavior, the device will bring the train to a halt in the event the engineer is unable to perform his/her duties.

How do alerters work?

Alerters, in the form of lights and audio signals, are connected to a timer. After a period of operation, visual and auditory signals activate and increase in intensity until the engineer pushes a reset button.  Failure to reset soon enough results in automatic braking and power reduction. 

Even with the new generation VCD systems, fatigue and alertness-related incidents and accidents still occur, which demonstrates the need for multiple ways to address attention-related challenges.


  • Wickens, C. (2015). Engineering Psychology and Human Performance. 4th Edition. New York: Harper Collins.
  • A. Kramer, D. Wiegman, & A. Kirlik (Eds.). (2007). Attention: From Theory to Practice. New York: Oxford University Press.