Radiology & Imaging

Researchers develop low-cost, portable brain imaging scanner

When it comes to brain scans for assessing head trauma, detecting brain cancer, and performing numerous other tests, magnetic resonance imaging (MRI) is the best option, but MRI scanners are costly, require special infrastructure, ...

Psychology & Psychiatry

Why our obsession with happy endings can lead to bad decisions

"All's well that ends well," wrote William Shakespeare over 400 years ago. The words may still seem to ring true today, but turns out they don't. We have just busted the old myth in a recent brain imaging experiment, published ...

Psychology & Psychiatry

Brain stimulation may increase control of emotional actions

To function well in society, people must be able to control their emotional reactions from time to time. This usually goes well, but this control can fail, for example with aggressive behavior in traffic or in people with ...

Psychology & Psychiatry

Why obeying orders can make us do terrible things

War atrocities are sometimes committed by 'normal' people obeying orders. Researchers from the Netherlands Institute for Neuroscience measured brain activity while participants inflicted pain and found that obeying orders ...

Oncology & Cancer

Scientists suggest device to make breast MRI more effective

Magnetic resonance imaging is becoming increasingly popular as a method of diagnosing diseases. Standard scanners are multifunctional, making it possible to cut down on the costs of specialized equipment. On the other hand, ...

Alzheimer's disease & dementia

Tracking down the cause of memory loss in Alzheimer's

Memory loss and confusion are signs of Alzheimer's disease. Physicists Serge Rombouts and Martina Huber have developed new methods to help medical science get to the bottom of this insidious disease.

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Magnetic resonance imaging

Magnetic Resonance Imaging (MRI), or nuclear magnetic resonance imaging (NMRI), is primarily a medical imaging technique most commonly used in radiology to visualize the internal structure and function of the body. MRI provides much greater contrast between the different soft tissues of the body than computed tomography (CT) does, making it especially useful in neurological (brain), musculoskeletal, cardiovascular, and oncological (cancer) imaging. Unlike CT, it uses no ionizing radiation, but uses a powerful magnetic field to align the nuclear magnetization of (usually) hydrogen atoms in water in the body. Radio frequency (RF) fields are used to systematically alter the alignment of this magnetization, causing the hydrogen nuclei to produce a rotating magnetic field detectable by the scanner. This signal can be manipulated by additional magnetic fields to build up enough information to construct an image of the body.:36

Magnetic Resonance Imaging is a relatively new technology. The first MR image was published in 1973 and the first cross-sectional image of a living mouse was published in January 1974. The first studies performed on humans were published in 1977. By comparison, the first human X-ray image was taken in 1895.

Magnetic Resonance Imaging was developed from knowledge gained in the study of nuclear magnetic resonance. In its early years the technique was referred to as nuclear magnetic resonance imaging (NMRI). However, as the word nuclear was associated in the public mind with ionizing radiation exposure it is generally now referred to simply as MRI. Scientists still use the term NMRI when discussing non-medical devices operating on the same principles. The term Magnetic Resonance Tomography (MRT) is also sometimes used.

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