The Left Brain Right Brain Myth

Are you logical, analytical and methodical in your thinking? You must be left-brained. Are you artistic, imaginative and creative? Well then you must be right-brained. This belief has been widely held for many years … and it’s not true. So where did this myth come from?Well this myth really came to light in the 1960s when Nobel prize winner Roger Sperry performed a series of experiments on volunteers who had their corpus callosum (a band of nerve fibres that connects the left and right sides of the brain allowing the two hemispheres to communicate) severed due to outside factors, most commonly epilepsy. It is worth noting that the right side of the brain tends to control the left side of the body vice versa. Similarly the left visual fields are sent to the right side of the brain and the right fields are sent to the left side of the brain.With this knowledge, Sperry asked participants to look at a white screen with a black dot in the centre. This black dot symbolised the dividing point for the fields of view for a person dividing the right side from the left side. Sperry then showed participants a word on either side of the black dot for just a moment and then asked them to tell him what they saw. When the participants saw the word with the right eye (and it was therefore processed with their left hemisphere) they were able to say what they saw. Conversely, when the participants saw the word with their left eye (processed by the right hemisphere) they could not remember what the word was. Sperry therefore concluded that the left hemisphere could recognise and articulate language while the right could not.Sperry conducted a number of similar experiments all suggesting differences in the functions of the two hemispheres of the brain. It would therefore be plausible to conclude that people exhibiting traits specific to the function of particular hemispheres of the brain would be dominant in this hemisphere right?Well … not really!Researchers at the University of Utah set out to dispel this myth over a two yearlong study in which the brains of over 1000 people aged 7-29 were studied. In each participant they studied functional lateralization of the brain for thousands of brain regions – or in other words, they studied the differences in the activity of brain regions across the two hemispheres (left and right). So what did they find?Well while it is true that some brain functions occur in one or the other side of the brain – for example, there are structures of the brain in the left hemisphere that tend to process language and structures on the right that tend to process things like attention, people don’t have a stronger left or right sided hemisphere of the brain. Furthermore, a lot of these functions tend to be processed in both hemispheres to varying degrees. For example in language the left side generally processes grammar and pronunciation while the right processes intonation.While this research is not to reject the fact that some people are more logical than creative and vice versa it does suggest that this does not infer a stronger left or right brain. Finally, there is generally quite a bit of overlap between logic and creativity. Inferring that these characteristics can be boiled down to one particular brain structure or hemisphere simply does not hold up. So the next time someone asks you if you are left or right brained you can confidently tell them that you are both!