The Left Brain, Right Brain myth

Probably one of the longest fallacy entrenched in human minds is the one about being left/right brain person, for example if someone is right handed they are “left brained” or vice versa. Or the fact that being left brained makes one more logical and rational/analytical implying having good mathematical skills, and being right brained makes one better in creativity or having a better imagination similar to an artist. Source of this myth dates back to physicians in 1800, who observed that having damage to one side of the brain caused person to lose some abilities specific to that half. Later came a book on that idea named ‘duality of the mind’ which described the two parts of the brain as being independently functional and working in different ways (this theory couldn’t be proven wrong because fMRI technology was still a century and a half away). This myth was further corroborated by classic severing surgeries of Corpus callosum (the connective bridge between two halves), these ingenious surgeries created totally unnatural brains, where the two halves could not communicate anymore. And what happened was stupefying: Now the two parts of the brain could actually work independently! These people could respond differently to stimuli provided to either their right or left side of the brain and they would get contrasting responses. For instance, when shown a picture to their right field of vision and asked to name it they were always correct but when it was shown to the left field of vision they could draw the same by their right hand, but could not say it. Mind=blown! The Nobel Prize winning scientist Roger Sperry did some of these experiments to find out which parts of the brain had functions related to math abilities, language, etc. But it was popular psychology fanatics who took this idea and stretched it too far from reality, the idea of human attributes being determined by dominants halves of the brain started spreading like fire. It started appearing in books, articles, editorial and what not. What made it worse were the personality assessment tests which were designed to tell you whether you’re a right brained/left brained person, books started cropping up based on the idea, there were even methods available to train the weak halves of your brain. One could not have thrown a dead cat around in the world web without hitting a page or app which offers such tests. What the research actually alluded to was the fact the certain processes are spatially centered to one area of the brain, and disrupting them would cause a loss of that particular function. Now there are functions in the brain which reside more in one part than the other, like language resides in left temporal lobe and attention resides in the right frontal hemisphere, but that is simply lateralization, it has nothing to do with one part being more dominant than the other. Brain lateralization has been known for almost 4 decades now and humans are not the only species which possess it. Fish, reptiles and other mammals are known to have it too. Brain lateralization is known to have some evolutionary advantage then, may be during evolution, organisms with lateralized brain could perform two tasks simultaneously or in parallel, like searching for food and keeping an eye out for predators. But, neither one is known to be dominating over the other. If anything they have functional connections. Almost all the functionally specific regions have connections to the other regions in the brain in ways which are complex yet almost mystical. For analogy consider the connections between proteins in a human cell. Each protein involved in one or the other process might still be regulated by others (I am sure you know by now that I study protein networks). Another analogy for you computer science geeks out there would be to imagine the brain not like a single computer with multiple hardware units, but more similar to gazillion computers connected through infinitude very very fast (almost 100 m/s) cables.

Let’s for now think about what could be better evidence to support this myth. It would involve studying the brains of mathematical wizards, analytical thinkers on one side and creative, imaginative people (anyone except politicians and bankers) on the other side. Measuring their brain activity could shed light on the fact that do they on an average use much more of their respective halves? (Some people actually manage quite well to use none). Well, there has been no evidence found yet to support this pop-notion idea (If someone is out there with the evidence now is the time for the real slim shady to stand up!). In fact the opposite evidence for this myth has been found in musicians having larger than normal Corpus callosum. Hence, learning music does not activate one part of your brain but improves the connectivity between different regions (For those of you who want to know more should see this exhilarating video of live brain imaging of a musician while he is playing an instrument, I call it brain ‘hustle’). Another landmark study conducted by Utah scientists triumphed in debunking this myth to some extent. They analyzed the brain scans of 1000 individuals and found absolutely no supporting evidence for left/right brain dominance. What they observed was already known that is the strong lateralization of brain regions like language processing in the left hemisphere, and attention predominantly showed right lateralization. These are so called hubs which light up when performing a task particular to their functional specification. Aha! Science: 1, pop-psychology: 0. Even though the hubs lit up, but they nonetheless received input from other areas of the brain. In the end everything in the brain is connected to mostly everything else. Sometimes it makes me wonder that how much important technology has been in promoting the information about the nature. This study would never have been possible without the dawn of fMRI. And we would all be blindly following the myth and pulling our hairs out while struggling to get the other half work as much better.

Where one part of the brain fails due to seizures or other conditions, other available regions take over certain functions. For example blind people being able to use the visual processing regions in their brain for processing sound in an enhanced manner, they have also been known to be used for processing language. Or the bio hacked guy (yes he is a cyborg) Neil Harbisson who had color blindness, but now can ‘hear’ colors through a camera antenna attached to his temple. What is amazing about this guy is that he not just perceives visible light but also infrared and UV light through various combinations of sound waves (and here comes the age of implantable technology to enhance human cognition). Even more enthralling phenomenon is of functional take over from parts whether damaged or not. Blind people are able to use visual areas to amplify sound processing, like daniel kish who uses echolocation to find his way. The regions in his brain which are usually known to be responsible for visual processing now light up when he does echolocation to make sense of his surroundings (by the way he can ride a bicycle on a busy road only with echolocation) what can be more counterintuitive? There are many more cases where people have hustle in the brain regions responsible for vision to the sound of approaching footsteps. Of course this was only possible for people who are congenitally blind or became blind in a very early stage, because then their brain was virgin enough to make connections to other regions and had enough time to do so. This is known as neuroplasticity. But then, looking at this evidence, it surely could not be said that one region is genetically hard wired to have only one particular function. During the research for this article I stumbled upon a report of an insane case where in a kid named ‘jake gladstone’ was born with almost his entire left half of the brain missing! What the F..k right ? One would expect such a kid to never be able to walk, talk, play or code (yes, that’s what many kids do these days for fun). Moreover, would he always be left brained? No! he is just like any other 4 year old, running around, talking. Although his language skills are not as same as kids of the same age, and have a dysfunctional right arm. But still it’s pretty amazing what his brain achieved given half the space it procured. He still solves math problems, paints and does everything a normal brain is capable of. Surely now the dominant half myth should be enclosed in a bag and thrown in a deep ocean. However, what would be interesting to know rather is whether there are chemical differences between the two halves. For instance if one half has higher distribution levels of a particular neurotransmitter than the other Or whether quantities of receptor channels are more on one particular half making it functionally more diverse. It would also be very intriguing to know any structural differences in connectivity within the two halves; can one half have more connections within itself? Or what if the two parts experience emotions differently? Can one half be more dominant in repressing the activity of the other half? The answer to these questions we have still yet to stumble upon.

In the end this particular myth might have been prevailing due to its simplicity. But remember however tough it might be, we still have to suppress our belief system and look at the truth even if it’s more complicated. I hope this myth might be a not more than a tiny hole in our ship who’s journey is to decipher how our brains really work! So if you want to tell yourself that you weren’t good at art because you’re a more left brained person( analytical, logical) then you should look for a better excuse, for this one will surely not help you anymore!!

Thanks for Reading. And remember to always stay curious.