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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:].