University of Calgary
UofC Navigation

Brain Facts

Brain Facts

Did you Know?

1. The brain uses approximately 20% of the oxygen we breathe 
2. The brain weighs roughly 3 pounds 
3. In general, the left side of the brain interacts with the right side of the body and vice versa
4. The skull protects the brain and is made up of 22 bones, joined together by immovable joints
5. The brain has about a billion nerve cells
6. The cerebral cortex of the brain contains more than 160 trillion connections or synapses
7. There are more connections in the brain than stars in the Milky Way
8. Nerve cells communicate through electrical impulses and neurochemicals
9. Electrical impulses are essentially tiny electrical currents that travel down the nerve fiber
10. The end of the nerve fiber, called the axon, releases neurochemicals
11. Neurochemicals travel between gaps in neurons, called synaptic gaps, and influence the activity of neighboring cells
12. Neurochemicals can activate or inhibit other neurons, affecting their communications with other cells in our body
13. Neural pathways become stronger and more efficient over time with continued use, which is why practicing helps us to learn
14. Every time we learn something our brains change
15. New nerve cells are created in a process called neurogenesis
16. Brain pathways that are inactive are eventually lost
17. The brain continues to change and adapt as we age
18. We have more neurons at birth than in adulthood, but we develop more specialized circuits of neurons as we age
19. Some brain areas, like the regions involved in emotion and memory, aren’t fully functional until we are at least 3-years-old
20. Brain-based traits, like intelligence and personality, are shaped by our genes and our environment
21. Brain diseases are also linked to certain genes and environmental toxins
22. Our brain doesn’t process all the sensory data that it is exposed to, but rather picks and chooses what is relevant
23. Our brain amplifies and ignores some sensory data based on our mood, values, and mindset
24. Our brain multitasks by activating and deactivating different neural circuits
25. Multitasking during a lesson can affect our brain’s ability to learn

Three Neuroscience Myths

The idea that we only use 10% of our brain is a myth that originated in early neuroscience research. Neurosurgeons stimulating the brain with electrodes observed that only 10% of the cortex responded with visible muscle twitches. However, now we know that brain responses are actually much more complex. In fact, there is a network of brain regions that remain active even when the brain is resting.

The idea that you are either a left-brain or right-brain thinker is a myth that is probably drawn from studies patients who had undergone a surgery severing the corpus callosum, which is a bundle of nerve fibers connecting the left and right hemispheres of our brain. These studies did uncover some important hemispheric difference in thinking; however, the findings have been exaggerated to describe different learning styles and personality types.

The idea that you can’t teach an old dog new tricks is a myth that has recently been challenged by a group of researchers from Stanford and Harvard, who showed that infusing an older mouse with blood from a young mouse reversed some of the effects of aging in the older mouse’s brain. In particular, the regions of the brain responsible for memory seemed rejuvenated and the mouse performed better on learning-related tests.

Sources:

Gazzaniga MS. Forty-five years of split-brain research and still going strong. Nature Reviews Neuroscience, August 2005. 6: 653-659.

Howard-Jones PA. Neuroscience and education: myths and messages. Nature Reviews Neuroscience, 2014. 15(12): 817-824.

James W. The Powers Of Men: The Keys Which Unlock Hidden Energies, and Stir Men to Achieve—Such Keys as Love, Anger, War, Duty, the Temperance ‘Pledge,’ Despair, Crowd-Contagion, Christian Science, Conversion, Prayer, Resistance of Temptation and Other Excitements, Ideas and Efforts. The American Magazine, 1907. 65: 57-65.

Katsimpardi L., Litterman N., Schein P., Miller C., Loffredo F., Wojtkiewicz G., Chen J., Lee R., Wagers A., and Rubin L. Vascular and Neurogenic Rejuvenation of the Aging Mouse Brain by Young Systemic Factors. Science, 2014. 9(344): 630-634.

Sherman, Carl. Q&A: Answering your Questions about Brain Research (2015). The Dana Foundation: Print Publications. Retrieved from http://dana.org/Publications/Print/

Sukel, K. When the Myth is the Message: Neuromyths and Education. (2015). The Dana Foundation: Briefing Papers & Reports. Retrieved from http://dana.org/Briefing_Papers/When_the_Myth_is_the_Message__Neuromyths...

Schnabel, J. A Fountain of Youth for the Brain? (2014). The Dana Foundation: News. Retrieved from http://www.dana.org/News/A_Fountain_of_Youth_for_the_Brain_/

Villeda S., Plambeck K., Middeldorp J., Castellano J., Mosher K., Luo J., Smith L., Bieri G., Lin K., Berdnik D., Wabl R., Udeochu J., Wheatley E., Zou B., Simmons D., Xie X., Longo F., and & Wyss-Coray, T. Young blood reverses age-related impairments in cognitive function and synaptic plasticity in mice. Nature Medicine, 2014. 20: 659-663.