I previously wrote an article talking about neuro nonsense, alerting you to the fact that not all (neuro)science is good (neuro)science. But let’s dive into more detail. What specific neuroscience “findings” are more fairytale than fact? Let’s start debunking!
1. We only use 10% of our Brains I personally love this one. Hollywood has made us believe that if only we could access the other 90% of our brains, we’d be capable of superhuman things. Like the movie Lucy, we’d end up turning into computers before vanishing into thin air whilst maintaining hyperconscious. The sci-fi genre has really gone into this topic (Limitless, Heroes, Defending Your Life, Flight of the Navigator), but unfortunately, it’s complete bulls—t. Modern brain scans show activity coursing through the entire brain, even when unconscious. Minor brain damage can have devastating effects on our (day-to-day) functioning, not what you'd expect if we had 90% spare capacity just lying about.
Also, consider the situation in which the function of some neural tissue is rendered redundant. For example, a brain area or neural tissue representing a limb, and then that limb is lost. Very quickly, neighbouring areas in the brain will recruit that tissue or area into new functions. The brain doesn’t leave any areas alone. The brain utilizes all available neural tissue.
If you still believe(d) in this myth, don’t worry, you are not alone. Even people who had neuroscientific training still endorse some of these myths. According to a survey done by ….. the 10 per cent myth was still endorsed by 36 per cent of the public, 33 per cent of teachers, and 14 per cent of those with neuroscience education. So, 1 out of 8 neuroscientists still thinks that they have 90% more of the brain to access. These findings are robust. In 2012, Dekker, et al, conducted a survey amongst school teachers in Britain and The Netherlands, and found that 48 per cent and 46 per cent, respectively, endorsed the myth. A US survey by the Michael J Fox Foundation for Parkinson's Research found that 65 percent of people believed in the myth. So hey, at least you're not alone. Consider yourself educated!
2. Left-brain vs. Right-brain This one annoys me, but the left-brain right-brain myth persists. It has just become a metaphor for different ways of thinking: logical, focused and analytic (left), as compared to broad-minded and creative (right).
There is, unfortunately, some truth to this myth, it’s not complete make believe. The two hemispheres of the brain do function differently. Most people seem to know that the left brain is dominant for language (and it is), whereas the right half of the brain is implicated more strongly in emotional processing and empathy. But the issue is that these distinctions are often taken too far. The right half is also involved in processing some aspects of language, such as intonation and emphasis. However, this fact is often conveniently forgotten.
We have learned a lot about the different halves from split-brain studies. Split-brain meaning a brain that has had the connection between the two hemispheres (corpus callosum) damaged (injury) or cut (as an early treatment for epilepsy). These studies have led to some interesting results.
It’s important to remember, however, that normally the two brain halves are connected. In most of what we do, the hemispheres have evolved to operate together, sharing information across the corpus callosum. Also do remember that the kind of tasks that engage one hemisphere more than the other, might be more difficult to categorise. Let’s take the example of creativity. Insight is one type of creativity, and one study did find that activity was greater in the right hemisphere when participants solved a task via insight, rather than piecemeal. Another showed that brief exposure to a puzzle clue was more useful to the right hemisphere, than the left, as if the right hemisphere were nearer the answer.
Telling stories is another form of creativity, an activity which mainly shows up in the left brain. Interestingly enough, one of the most fascinating insights from the split-brain studies was the way the left hemisphere seemed to make up stories to explain what the right hemisphere was doing. A patient completing a picture-matching task used their left hand, which is controlled by the right hemisphere, to match up a shovel with an image of a snow storm, which was only shown to the left eye, also controlled by the right hemisphere. The patient was then asked why they had done this. But their left hemisphere, which is the source of speech, did not admit to not knowing this. Instead, it made up a story, saying that they had reached for the shovel to clear out the chicken coop. Chicken coop? Yes, the picture shown to the right eye, so the left hemisphere was of a bird’s foot. I mean, you have to say something…
So, although there is many self-help books, guru’s, personality tests, apps and courses out there trying to convince you to fulfil your full potential as a left-brained or right-brained individual, however, the truth is much more complex.
3. The Brain is Gendered It is widely believed that girls and boys show different aptitudes in key cognitive skills, with girls being better at language and boys performing better with regards to technical subjects like science and mathematics. And yes, gender differences do exist (to some extent), but is this due to the brain itself?
Hyde (2005) has gathered 46 meta-analyses, which totaled the data of 7 million people, looking at gender differences across behaviours as diverse as language skills to throwing ability. She found that 78% of the studies showed gender differences to be small or negligible, even in areas classically held to robustly distinguish between males and females.
This lack of difference replicates with data from children. Hyde points out that the National Assessment of Educational Progress in America found less than a 4-point difference in science ability between 9-10 year old boys and girls on a 300 (!!) point scale. Others have found similarly negligible gender gaps when using large national data sets, with small differences in maths achievement emerging only at the very end of school (Leahey & Guo, 2000).
Who says higher performance has to come from aptitude per se? There is a lot of finance literature exploring the differences between men and women. It seems that men and women use different strategies. When navigating women tend to use landmarks and men tend to use geometric information, like actual roads. When only one of these sources of information is available to complete a navigation task men and women perform equally well (Spelke, 2005). Men and women have also been shown to use different strategies on word fluency tests, with women increasingly switching between categories: if asked to name animals a woman might start with farm animals but then move on to zoo animals, whereas a man might try harder to stick with farm animals. This switching leads to naming more animals overall (Weiss, et al, 2006). I like these tests, because they are able to reject both the gendered-brain myth, and the left-brain right-brain myth at the same time.
And honestly, it’s not the brain. It’s us, our society and our expectations. The impact of expectation seems to start early. Parents have been found to hold lower expectations for their daughters compared to their sons when it comes to mathematics (Lummis & Stevenson, 1990). How people think they are perceived can have a real impact on performance. By age 8-9, girls and their parents rated their math skills lower than those of boys, even though there was no actual basis for this lower rating: there was no actual difference in performance (Herbert & Stipek, 2005).
New dogs, old tricks; When college students was given a maths test, men outperformed women, but only when told that the test usually revels gender differences. When told it was a gender fair test, no such difference emerged and performance was equal (Spencer, et al, 1999). How quickly do you think a female brain turns against its owner?! The “gendered brain” does not predict these gender gaps in performance.
You know what does seem to predict the size of gender gaps in different countries at school age? Female representation in parliament and gender equity in school enrollment (Else-Quest, et al, 2010).
So, there are differences between men and women, but those differences are smaller than we are led to believe, and probably mainly due to strategy differences and/or societal expectations. Any differences that do exist are not nearly as heavily brain-based as thought!
Conclusion As I said in my previous article, and I will happily reiterate it. Seek the Science. Science with a capital S that is. Not the stuff they try to sell you an app with. Nor the books that tell you that you’ll be a great CEO because you fit one description of creativity. And definitely not the stuff that tells you that you shouldn’t be, or can’t be an engineer as a woman, or a nurse as a man because of your brain. This has no real foundation in real neuroscience. It’s time we stop reading fairytales, and wake up to the facts. May neuroscience live happily ever after!
References Dekker, S., Lee, N. C., Howard-Jones, P., & Jolles, J. (2012). Neuromyths in education: Prevalence and predictors of misconceptions among teachers. Frontiers in Psychology, 3, 429.
Else-Quest, N. M., Shibley-Hyde, J., & Linn, M. C. (2010). Cross-national patterns of gender differences in mathematics: a meta-analysis. American Psychologist, 136 (1)
Herbert, J., & Stipek, D. (2005). The emergence of gender differences in children’s perceptions of their academic competence. Journal of Applied Developmental Psychology, 26 (3), 276-295.
Hyde, J. S. (2005). The gender similarities hypothesis. American psychologist, 60(6), 581.
Leahey, E., & Guo, G. (2000). Gender differences in mathematical trajectories. Social Forces, 80, 713–732.
Lummis, M., & Stevenson, H. W. (1990). Gender differences in beliefs and achievement: A cross-cultural study. Developmental Psychology, 26, 254–263.
Spelke, E. S. (2005). Sex differences in intrinsic aptitude for mathematics and science? American Psychologist, 60 (9), 950-958
Spencer, S. J., Steele, C. M., & Quinn, D. M. (1999). Stereotype threat and women’s math performance. Journal of Experimental Social Psychology, 35, 4–28.
Weiss, E. M., Ragland, J. D., Brensinger, C. M. Bilker, W. B., Deisenhammer, E. A., & Delazer, M. (2006). Sex differences in clustering and switching in verbal fluency tasks. Journal of the International Neuropsychological Society, 12 (4), 502-509.