Are you really only using 10 percent of your brain?

Brain-imaging Tools

Unlike their 19th century predecessors, who had to be content with mucking around with scalpels and shooting electricity into random spots of the brain to see what happened, today's neuroscientists have at their disposal an array of sophisticated technology for probing the mysteries of how the brain works.

One extremely useful tool for researchers who treat brain diseases and injuries is functional magnetic resonance imaging (fMRI), which uses a powerful magnetic field, radio frequency pulses and a computer to produce a series of detailed pictures of a person's brain as it works. An fMRI not only provides a look at brain's anatomy, but also to determine precisely which parts are handling activities such as thinking, speech, movement and sensation. (That sort of study is called brain mapping) [source:].

Another way to look at the brain is to use a computerized axial tomography (CT) scan, which takes a series of X-rays of the brain and uses a computer to combine them into an image [source: National Headache Foundation]. Yet another imaging technology is the positron emission tomography (PET) scan. For this scan, a small amount of radioactive material is injected into a vein, inhaled or swallowed. The radioactive material accumulates in the brain and gives off gamma rays, which are captured with a special type of camera [source:]. PET scans are useful for identifying brain abnormalities and studying which parts of the brain are most active during certain tasks [source: Mayo Clinic].

Sophisticated brain-imaging tools also enable neurosurgeons to plan operations and to cut with more precision when they remove tumors, so that there is less damage to patients' brains. When a talented young French horn player was recently diagnosed with a large brain tumor, for example, doctors feared that it might end his musical career. Dr. Susan Bookheimer, a neurosurgeon at UCLA medical school, had him undergo an fMRI scan while reading sheet music and fingering an instrument, so she could pinpoint the areas of the brain he was using. As a result, surgeons were able to avoid damaging those areas when they removed the tumor, and the musician was back playing in a few months [source:].

Related HowStuffWorks Articles


  • ABC News. "20/20 Busts 10 Body Myths." June 23, 2006. (July 20, 2009)
  • Senior Health. "Mapping Alzheimer's Disease Path." July 20, 2006. (July 21, 2009)
  • "UCLA Brain Imaging Research-Functional Magnetic Resonance Imaging." 2009. (July 21, 2009)
  • Beyerstein, Barry L. "Do we really use only 10 percent of our brains." Scientific American. March 8, 2004. (July 20, 2009)
  • Boyd, Robynne. "What's the matter with only exploiting a portion of our gray matter?" Scientific American. Feb. 7, 2008. (July 20, 2009)
  • California Institute of Technology. "Einstein Archives Online." Undated. (July 21, 2009)
  • Carnegie, Dale. "How to Win Friends and Influence People." Simon & Schuster. 1982. (July 21, 2009)
  • Carroll, Aaron, and Vreeman, Rachel. "Don't Swallow Your Gum! Myths, Half-Truths, and Outright Lies About Your Body and Health." St. Martin's Griffin. 2009. (July 21, 2009)
  • Cordon, Luis. "Popular Psychology: An Encyclopedia." Greenwood Press. 2005. (July 21, 2009)
  • Cornell University. "Ask A Scientist." Aug. 29, 2007. (July 20, 2009)
  • Della Sala, Sergio. "Tall Tales About the Mind and Brain." Oxford University Press. 2007. (July 20, 2009)
  • DeMoss, Robert T. "Brain Waves Through Time: 12 Principles for Understanding Evolution of the Human Brain and Man's Behavior." Plenium Trade. 1999.
  • Finger, Stanley. "Minds Behind the Brain: A History of the Pioneers and Their Discoveries." Oxford University Press. 2005. (July 20, 2009),&source=gbs_navlinks_s
  • Heath, Chip and Heath, Dan. "Why do some ideas succeed while others fail?" Stanford Business Magazine. February 2007. (July 20, 2009)
  • Helium. "Debate: Do Humans Only Use 10 Percent of Their Brain?" Undated. (July 20, 2009)
  • Higbee, Kenneth L., and Clay, Samuel L. "College Students' Belief in the Ten-Percent Myth," Journal of Psychology,1998, Volume 132, Issue 5, page 469-475. (July 20, 2009)
  • James, William. "Memories and Studies." Longmans, Green and Co. 1911 (July 20, 2009)
  • Johnson, George. "How Much Give Can the Brain Take?" The New York Times. Oct. 24, 1999.
  • Kruszelnicki, Karl and Yazxhi, Adam. "Great Mythconceptions: The Science Behind the Myths." Andrews McMeel Publishing. 2006. (July 20, 2009)
  • Mayo Clinic. "Positron emission tomography (PET) scan." May 8, 2009. (July 21, 2009)
  • National Headache Foundation. "CT Scan." 2009. (July 21, 2009)
  • Parker-Pope, Tara. "Medical Myths Even Doctors Believe," The New York Times. Dec. 26, 2007.
  • Persaud, Raj. "You Need Your Brain-All of It," The Times Educational Supplement. May 13, 2005.
  • Pickover, Clifford A. "Strange Brains and Genius: The Secret Lives of Eccentric Scientists and Madmen," Harper Perennial. 1999 (July 21, 2009)
  • Psyblog, "Seriously, Would You Admit to Only Using 10% of Your Brain?" February 2008. (July 20, 2009)
  • Radford, Benjamin. "The 10 Percent Myth." Skeptical Inquirer. March/April 1999. (July 20, 2009)
  • "Functional MR Imaging (fMRI) - Brain." June 20, 2009. (June 21, 2009)
  • "Positron Emission Tomography - Computed Tomography (PET/CT). June 15, 2009. (July 21, 2009)
  • "Scans show dramatic brain cell loss in Alzheimer's." Feb. 6, 2003 (July 21, 2009)
  • Wanjek, Christopher. "Bad Medicine: Misconceptions and Misuses Revealed, from Distance Healing to Vitamin O." Wiley. 2002. (July 21, 2009)
  • Williams, Geoff. "Myth Buster: Ten Percent of Your Brain." AARP Bulletin Today. June 26, 2008. (July 20, 2009)
  • Zweifel, Thomas D. "Communicate or Die: Getting Results Through Speaking and Listening." Swiss Consulting Group. 2003. (July 21, 2009)

More to Explore