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Myth busting our brain

By Shaun Holt


Our brains weigh around 1.4kg, about the same weight as a laptop computer, but with far more processing power! And I take no pleasure in saying this, but male brains are on average around 10% larger than female brains, presumably because they are less efficient. However, studies have shown that brain size does not correlate with intelligence.

What is the brain made of? Mostly fat actually, but this fat helps to make up brain nerve cells, of which we have around 86 billion. The electrical power which these cells produce has been estimated to be around 23 watts, in other words, only enough to power a small lightbulb.

The structure of the brain is very complex. But overall, the largest part, 85%, is called the cerebrum. This is divided into two hemispheres, and each hemisphere has 4 lobes which have different functions:

frontal lobe - thinking, planning, moving

temporal lobe - memory, emotion

parietal lobe - spatial orientation

occipital lobe - vision

The two hemispheres have different roles as well, and you may not have heard about “left brain” and “right brain” qualities. In general, the left brain focuses more on language, comprehension and math skills, and the right brain focuses more on hearing, spatial skills and creative skills.

As well as the cerebrum we have the brainstem, which connects to the spinal cord and relays information between the brain and the body. Other smaller but no less important parts of the brain are the thalamus, hypothalamus, cerebellum, and the fluid-filled ventricles.

There are a couple of myths about the brain which I think would be well worth debunking.

Firstly, something I discovered the hard way, is that the brain cannot multitask. Instead, what the brain does is keep switching from one task to another and this results in more errors and it taking longer to complete tasks. The studies are clear on this - it is far more efficient to focus on one thing at a time.

Secondly, one of the biggest myths in medicine is that we only use 10% of our brain - around 65% of people believe this. In fact, brain imaging studies show that the majority of the brain is almost always active. Even when we are resting or sleeping a lot of the brain is being used. It is a mystery where this myth originates from. Most likely, it comes from Dale Carnegie’s 1936 book How to Win Friends and Influence People.

As to what a person can do to improve or maintain brain health, this is mostly the same as for general health e.g. eating a healthy diet with lots of fruit, vegetables, antioxidants and oily fish, and exercising regularly. In addition, keeping the brain active certainly helps, with activities such as reading, sudoku and brain training exercises. And there are various nutritional supplements, including fish oil, which are thought to help as well.