Why we forget


Why we forget

We are bombarded with information which our brain needs to process. While that information makes it to our short-term memory, there isn’t enough capacity to keep it there. Our brain ends up having to decide between forgetting that information or storing it as long-term memory. If not, you will get a ‘memory overload’. This means that even the most powerful learning experiences will be ineffective, as memory overload will prevent us from absorbing and retaining information for later use.

For learning and development professionals, this presents an obvious challenge. To tackle this challenge you need to understand what the forgetting curve is, and more importantly, the impactful tactics you can use to overcome it.

Why we forget

German psychologist Hermann Ebbinghaus wanted to understand more about why we forget things and how to prevent it. He experimented with his own ability to remember using a list of nonsense syllables, which he attempted to recall after different lengths of time. His research produced the Forgetting Curve, a visual representation of the way that learned information fades over time. His research dates back to the 1880s. In 2015, a research team successfully reproduced his findings, and concluded that his methods and theories still hold true today.

Ebbinghaus’ experiences and results revealed a number of key aspects of memory:

  • Memories weaken over time. If we learn something new, but then make no attempt to relearn that information, we remember less and less of it as time goes by.
  • The biggest drop in retention happens soon after learning. This is reflected by the steep fall at the start of the Forgetting Curve. Without reviewing or reinforcing our learning, our ability to retain the information goes down.
  • It's easier to remember things that have meaning. Things with little or no meaning (like the nonsense syllables Ebbinghaus tried to learn) conform most closely to the Forgetting Curve.
  • The way something is presented affects learning. The same set of information can be made more or less memorable, depending on how well it's communicated.
  • How you feel affects how well you remember. Ebbinghaus believed that physiological factors, such as stress and sleep, play a significant part in how well we retain information. There's also strong evidence to suggest that sleep can help our brains to sort and store information.

Learners forget 90%

Based on the Ebbinghaus’ Forgetting Curve, learners will have forgotten an average of 90% of what they have learned within the first month. However, the nature of the subject matter, the learner's background, the learner’s strength of memory and a variety of other factors will often have a significant impact upon the rate of forgetfulness.

How to avoid memory overload

The primary goal of any online learning course or event is to offer learners a chance to fully absorb new skills and knowledge. By using the forgetting curve in learning design and development, you have the power to create online experiences that are memorable and highly effective,

Keep the following tips in mind to avoid memory overload

  1. Learners must know why they have to acquire the information offered in your course in order to become fully engaged. By doing so, the experience becomes more memorable and powerful, which can boost knowledge retention. Tie learning activities into real world challenges and benefits. Encourage them to put the information to use by integrating online scenarios or simulations, so that they will realize the consequences or rewards of learning this new information.
  2. Upon completion of each module, learners should be assessed to see how much knowledge they have gathered. It will allow the learners to review and put the information into practice almost immediately. Quizzes, tests, and learning activities that encourage learners to recall information in their own words are ideal assessment exercises.
  3. Learners who aren't acquiring or retaining the information as effectively as their peers should be asked to attend follow-up learning sessions. This may be within a week of the initial session or a month, depending upon the subject matter and the scheduling. At the end of the follow-up session, another assessment should be conducted to measure their progress.
  4. Develop modules or online courses that are “bite-sized”, so that you can help to prevent memory overload. Have the learners go at their own pace, so that there is no pressure to keep up with their peers. This gives them the opportunity to fully absorb information and commit it to memory before exploring the next topic.

Keep this forgetting curve on hand to boost knowledge retention when developing your next learning program. Make it memorable, engaging, and effective for your audience!

Arjan Toet

Arjan Toet

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Arjan Toet

Learning Architect, Director