According to scientists, we have more knowledge about stars than we have about the human brain. Our brain may only weigh 3 pounds, but it is complex and mysterious. When you consider that we have around 86 billion neurons1 (formerly believed to be 100 billion) that create more than 100,000 chemical reactions in the brain every second, it makes sense that our understanding of the brain continues to evolve over time.
It has been said that we only use 10% of our brain. However, with brain scanning technology, we now know we use our entire brain all the time. When you consider the brain is about 3% of our body’s weight and uses 20% of our body’s energy, you can see that our brains are really busy!
Another myth about the brain is the idea that if you’re mostly analytical and logical in your thinking, you’re said to be left-brained. If you tend to be more creative or artistic, you’re thought to be right-brained. While it may be correct to say that different sides of the human brain have specific functions, we do not generally use one side more than the other.
Beyond how we think, physical activity also provides an interesting left vs right brain fact. The human brain is divided into two hemispheres. The left brain controls the right-hand side of the body, and the right brain controls the left side! (More to come on this in future posts.) Needless to say, the neural networks that connect one side of the brain to the opposite side of the body are incredibly intricate. As a result, there are many movement disorders, such as essential tremor, that remain a puzzle to researchers. This lack of knowledge has led to treatments that often have limited effectiveness, or when therapies do work, the reason why may not be clear.
While medications can be prescribed to treat essential tremor, there are no medications that were developed specifically for the condition, and it is estimated that 30-50% of patients don’t get satisfactory tremor relief from medications.2 Interestingly, surgical procedures for essential tremor have focused on the thalamus, located near the center of the brain. As one example, the focused ultrasound treatment for essential tremor targets the thalamus.
The thalamus is a part of the brain stem, the most primitive part of the brain, which sits above the spinal cord. From this vantage point it relays sensory information (sound, sight, touch and taste) to the cerebral cortex, and is considered an integral part of the neural network related to motor control. For this reason, it has long been the target for treating movement disorders.
There is much we do, and do not, currently understand about the brain. New facts are coming into play all the time as researchers continue to explore and try to understand how our brains work. There is great hope that what we learn can improve the lives of people with challenging conditions around the globe.
2Zesiewicz,T.A. et al. Evidence-based guideline update: Treatment of essential tremor. Neurology November 8, 2011 vol. 77 no. 19 1752-1755