Imagine you’re put in charge of your company’s biggest leadership training program. You do everything right: you conduct extensive discovery with your subject-matter experts, you spend weeks authoring the storyboard, your executive team signs off, and you deliver a stellar training experience. Everything goes beautifully and everyone agrees the training was a huge success. Your work is done.

But back in your office, while you bask in the glory of your success, a dreadful thing is happening inside the brains of your students. The neural networks that your training inspired are beginning to dissolve, and as a result, your employees are quietly forgetting almost everything you presented.

How bad is the problem? How much do people forget? Research on the forgetting curve (Figure 1) shows that within one hour, people will have forgotten an average of 50 percent of the information you presented. Within 24 hours, they have forgotten an average of 70 percent of new information, and within a week, forgetting claims an average of 90 percent of it. Some people remember more or less, but in general, the situation is appalling, and it is the dirty secret of corporate training: no matter how much you invest into training and development, nearly everything you teach to your employees will be forgotten. Indeed, although corporations spend 60 billion dollars a year on training, this investment is like pumping gas into a car that has a hole in the tank. All of your hard work simply drains away.


Figure 1:
The forgetting curve

And it gets worse. Given that our employees forget most of what they learn, we should have no hope that our training will transfer back to the workplace. After all, memory is a necessary condition for behavior change, and if your employees have forgotten the lessons of your leadership seminar, there is no reason to expect them to become more effective leaders back in the workplace.

Why do people forget so much?

As a learning professional, it is essential that you understand why we forget, and so I will address the issue this month. Next month, I begin discussing ways to overcome the forgetting curve.

Everyone is always bragging about the power of the human brain. So if it is so darned powerful, why does it fail so often? Why do we forget 90 percent of what we learn within one week? From the perspective of a neuroscientist, this question speaks to a fundamental misunderstanding about the brain and about forgetting. Whereas most people think of forgetting as a failure of memory, “I forgot because my memory failed,” in professional neuroscience, forgetting is not thought of as a failure at all. Instead forgetting is thought of as a natural, adaptive, and even desirable activity.

Let me explain. At this moment, thousands of sensory inputs are inundating your brain and your brain is busy ... ignoring them. For example, sensory impulses are racing from your left ankle telling your brain about its position in space. However you were not aware of this sensory information until I brought it to your attention because your brain was actively suppressing that input. Simultaneously, other inputs are arriving and your brain is ignoring them too. For example, your brain is ignoring the background noise in the room, the feel of clothing against your shoulder, and perhaps a faint odor of coffee in the room. 

You get the idea ... at every moment sensory information is flooding your brain, and your brain actively suppresses most of it using center-surround neural networks (see the end of the article for more information). This suppression is highly adaptive because, by suppressing most information, you are now free to focus on what you think are the one or two more essential pieces of information.

You need to experience this for yourself. Please watch this 90-second YouTube video and discover how our selective attention makes us oblivious to most information in the environment.

Avoiding memory overload

If our brain suppresses active sensory inputs, it also needs to suppress active memories so that it can focus only on essential information. When you think about it, every minute of the day we receive a river of information that is relevant only for a short period of time. For example, you may have remembered the phone number of a restaurant for a couple of minutes, but then it was no longer useful, and your brain managed to quickly forget it. Likewise, you parked your car last Thursday and you remembered where it was for the rest of the day, but now that the information is no longer useful, your brain has forgotten it. 

The point here is that your brain needs to forget things that are no longer useful. And this forgetting is inevitable, it is useful, and it is adaptive because it clears your memory for things that are more relevant. The problem, however, is that in the process of all of this memory purging, our brain often forgets important information.

Is there any hope?

Your leadership training did indeed go well and you deserve credit for it. But when you go back to your office, you can’t afford to bask in your success because, although the training went well, the ideas are quickly and quietly leaking out of the gas tank. But here is good news and there is hope. 

Although the brain will inevitably purge most of what it learns, it does retain some information, and contemporary neuroscience has discovered the signals that teach your brain which signals to remember and which information to purge and which information to retain. Next month, we will teach you ways to talk to the brain, and tell it to retain the important information.

Digging deeper

If you want to dig deeper, here are some great resources:

This two-minute YouTube video provides a great introduction to neural networks

Learn about Center-Surround neural networks (advanced)

Explore selective attention and the invisible gorilla