Neuromyth – We Only Use 10% of Our Brains
February 22, 2018
By Dr Lieb Liebenberg

Introduction

The 10% neuromyth plays itself out in different ways and variations in popular culture of which perhaps the most well-known recent example is the movie “Lucy” showing the heroine achieving amazing feats as she uses more and more of her (drug-induced) brain capacity. The movie and series “Limitless” is based on the same myth.

If this neuromyth only played out in popular culture it would be harmless, but unfortunately, it often manifests itself in teaching environments – especially in the way that teachers structure their direct instruction or even project-based lessons and the amount of information they require of students to mentally manage at a given time. One metaphor which probably explains this is where students are seen as “empty sheets” of paper on which a teacher simply has to “write” their expert knowledge. Another would be to see their brains as supercomputers that have vast amounts of storage space and almost unlimited processing capacity.

However, one of the lessons we have learned from the field of Mind, Brain and Education (MBE) in the last couple of decades is that students do not have unlimited capacity – especially not in their working memory. Also research has pointed out that the mastery of knowledge is dependent on the existence of prior knowledge. This is discussed in more detail in the next section, starting with a (simplified) model of remembering and forgetting:

As the model shows, humans have a limited working memory (both in capacity as well as in timespan)  and depending on whether a piece of information grabs ones attention, memorisation relies heavily on the ability to link new information to existing knowledge (which resides in long-term memory). This has serious implications for classroom practice since it stresses the importance, both of the expected prior knowledge that the curriculum expects, but also about the way in which a teacher introduces new information. Failure to link to existing knowledge (or at least what is expected to be known) will make it extremely difficult for memorisation to take place – irrespective of whether we are talking about a “pure fact” or a technique for solving quadratic equations.

Of course, teachers have no way of knowing precisely what resides in each student’s long-term memory, which makes their task even more difficult. This also explains the importance of revising “old” work before new material is introduced, which experienced teachers often do, although this is of course not always possible.

In addition to alerting us to the importance of prior knowledge, the model warns us that if a teacher introduces new material in such a way that it requires more than the available working memory of students it will make the mastery of that material extremely difficult, no matter how sound their foundational knowledge about the topic is.

This also has implications for project-based teaching, because it makes little sense to expect of students to discover and learn new concepts as part of a comprehensive project if those are not clearly defined by the teacher up front and s/he ensures (as far as is possible) that students possess sufficient prior/foundational knowledge to enable actual learning. Projects should also be structured in such a way that students’ working memory will be able to cope with the amount of new information they need to process as they progress. Encouraging students to frequently summarise their learnings and sharing them with their peers as they progress through the project will go a long way towards achieving this and leading to real learning. Perhaps most importantly, it will enable critical thinking and foster creativity because their working memory will have the necessary “spare” capacity to do so.

Conclusion

Although the 10% neuromyth may lead to some interesting popular fiction, its influence in education must be avoided at all costs. Even where teachers do not adhere to this myth, they should be aware of the limitations of working memory and the interaction between new facts and prior knowledge when structuring their direct instruction lessons, flipped classroom materials or classroom projects.