MRI is short for "magnetic resonance imaging". The MRI scanner does not use any x-radiation or ionizing radiation like x-rays or a Cat Scan does. To get pictures of your brain, the MRI scanner uses very strong magnet, and radio-frequency antennas to spin tiny atoms inside your body to help them send "signals" back to more antennas that will listen for those signals, send the analog wavelengths to computers to convert them to digital signals to create computerized images which will create highly detailed images of your brain.
