8 Facts About the Brain

Brain and calculations (drawing)

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While researchers are still uncovering the secrets of how the brain works, they have discovered plenty of information about what goes on inside your head. Unfortunately, there are still a lot of misunderstandings about the brain. The following are the facts behind just a few of the many misconceptions.

We Don't Just Use 10% of Our Brains

Have you ever heard that we just use 10% of our brains? It's an oft-cited statistic, but constant repetition does not make it accurate. People often use this inaccurate stat to imply that the mind is capable of much greater things, such as dramatically increased intelligence, psychic abilities, or even telekinesis.

If the 10% number were true, brain damage would be far less likely—after all, we would only have to worry about that tiny 10% of our brains being injured.

The fact is that damage to even a small area of the brain can result in profound consequences for both cognition and functioning. Brain imaging technologies have also demonstrated that the entire brain shows levels of activity, even during sleep.

Brain Damage Isn't Always Permanent

The brain is fragile and can be damaged by things such as injury, stroke, or disease. This damage can result in a range of consequences, from mild disruptions in cognitive abilities to complete impairment. Brain damage can be devastating, but is it always permanent?

A person's ability to recover from brain damage depends upon the severity and the location of the injury. For example, a blow to the head during a football game might lead to a concussion. While the injury can be quite serious, most people can recover when given time to heal. A severe stroke, on the other hand, can result in damage that can very well be permanent.

However, it is important to remember that the human brain has an impressive amount of plasticity. Even following a serious brain event, such as a stroke, it is possible for the brain to partially or fully heal itself over time and form new connections.

People Aren't Fully Right- or Left-Brained

Have you ever heard someone describe themselves as either left-brained or right-brained? This idea stems from the popular notion that people are either dominated by their right or left brain hemispheres. According to this idea, people who are "right-brained" are believed to be more creative and expressive, while those who are "left-brained" are positioned as more analytical and logical.

While experts do recognize that there is lateralization of brain function (that is, certain types of tasks and thinking tend to be more associated with a particular region of the brain), no one is fully right-brained or left-brained.

In fact, we tend to do better at tasks when we engage the entire brain, even for things that are typically associated with a certain area of the brain.

Humans Don't Have the Biggest Brains

The human brain is quite large in proportion to human body size, but humans don't have the largest brains of any organism. How big is the human brain? How does it compare to other species?

The average adult brain weighs about 3 pounds and measures about 15 centimeters in length. The largest animal brain belongs to that of a sperm whale, weighing in at a whopping 18 pounds! Another large-brained animal is the elephant, with an average brain size of around 11 pounds (5 kilograms).

But what about relative brain size in proportion to body size? Though the proportion of the human brain to the human body is larger than many animals, the notion that it's the largest is also inaccurate. Surprisingly, one animal with a larger brain-to-body weight ratio than humans is the shrew, with a brain that makes up about 10% of its body mass.

New Brain Cells May Form Throughout Life

Traditional wisdom has long suggested that adults only have so many brain cells and that we never form new ones. Once these cells are lost, are they gone for good? Experts have uncovered evidence that the human adult brain does indeed form new cells throughout life, even during old age.

The process of forming new brain cells is known as neurogenesis, and researchers have found that it happens in at least one important region of the brain called the hippocampus.

It's worth noting, however, that research on this topic is mixed, and some neuroscientists don't consider this a proven theory, according to the National Institute of Health (NIH).

Alcohol Can Affect Your Brain Cells

Partly related to the misconception that we never grow new neurons is the idea that drinking alcohol can lead to cell death in the brain. Drink too much or too often, some people might warn, and you'll lose precious brain cells that you can never get back. Could drinking alcohol really kill brain cells?

Researchers don't believe that alcohol use actually kills brain cells, though evidence does suggest that it can inhibit new cell growth. Additionally, long-term use can have a significant impact on brain functioning.

There Are About 85 Billion Neurons in the Human Brain

An often-cited statistic is that there are 100 billion neurons in the human brain. This number has been repeated so often and for so long that no one is completely sure where it originated. In 2009, however, one researcher decided to count neurons in adult brains and found that the number was just a bit off the mark.

Based on this research, it appears that the human brain contains closer to 85 billion neurons. So while 100 billion is a few billion too high, 85 billion is still nothing to sneeze at.

Using Learning Styles Isn't Necessarily Effective

Learning styles suggest that each person has a preferred learning style that helps them learn best. For example, one popular theory proposes that people tend to be more auditory, visual, or kinesthetic learners. In other words, some people learn best by hearing, seeing, or doing.

While it's an appealing concept, there's little research to suggest that learning based on your preferred style actually has any impact on learning outcomes. One large-scale study found no evidence to support the use of learning style assessment instruments. 

A Word From Verywell

There is still a lot that we don't know about how the brain works, but there is a lot that we do know. Learning more about how the brain works can help you better understand some of the factors that may affect your mental health.

9 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Kendra Cherry
Kendra Cherry, MS, is an author and educational consultant focused on helping students learn about psychology.