How many tasks are you performing right now? You probably have your phone in your hand checking email or waiting on a text. Maybe your television is on in the background waiting for the news report to begin. Then of course, you’re trying to read this blog. All the while your brain is trying, but failing, to multitask.

Stop. Put down the phone. Turn off the television. Close those other windows on your desktop. Give us five minutes of your undivided attention. You’ll see in a minute why it’s so important.

Understanding attention limits of humans is an important factor in the design of products and systems. Persons do not perform well when trying to perform two attention demanding tasks at the same time.

For example, during two cognitively complex tasks, such as driving and talking on the phone, the brain shifts its focus and people develop “inattention blindness.” Inattention blindness is a tendency to look at but not see objects. It is estimated that drivers using cell phones, including through hands free means, look but fail to see up to 50 percent of information in their driving environment.

According to the National Safety Council, the brain engages in a constant process to deal with information it receives by selecting the information the brain will attend to, processing the information, encoding the information (a stage that creates memory,) storing the information, retrieving the stored information, and then executing upon the information. When the brain is overloaded all of these steps are affected. However, people do not realize this challenge is occurring within their brains.

When persons maintain they can multitask, they do not understand how the brain processes information for decision-making. Human brains do not perform two tasks at the same time. Instead, the brain handles tasks sequentially switching between one task and another. When brains juggle tasks rapidly, it leads to the erroneous conclusion that people are able to do two tasks at the same time. In reality, the brain is switching attention between the tasks performing only one task at a time.

Designers of products and systems need to understand limitations of humans attention and design systems to eliminate or minimize human error due to humans limitations regarding attention; after all, to err is human, design forgives.

For more information on human attention capabilities we recommend downloading “Understanding the Distracted Brain,” from the National Safety Council.