Medical research

Why thinking hard makes you tired

It's no surprise that hard physical labor wears you out, but what about hard mental labor? Sitting around thinking hard for hours makes one feel worn out, too. Now, researchers have new evidence to explain why this is, and, ...

Neuroscience

To better understand the brain, look at the bigger picture

Researchers have learned a lot about the human brain through functional magnetic resonance imaging (fMRI), a technique that can yield insight into brain function. But typical fMRI methods may be missing key information and ...

Neuroscience

The brain already benefits from moderate physical activity

Exercise keeps body and mind healthy—but little is known about exactly how and where physical activity affects our brains. "In previous research, the brain was usually considered as a whole," says Fabienne Fox, neuroscientist ...

Neuroscience

Researchers provide new framework for studying brain organization

UCLA researchers and colleagues at Emory University and other research centers have combined data simulation and experimental observation to bridge a gap between two major properties of large-scale organization of the human ...

Cardiology

Advanced MRI benefits patients with heart stiffening disease

An advanced form of cardiac MRI, developed by academics at UCL in collaboration with the Royal Free Hospital, has for the first-time enabled clinicians to measure the effectiveness of chemotherapy in patients with the life-limiting ...

Health

Moderate drinking linked to brain changes and cognitive decline

Consumption of seven or more units of alcohol per week is associated with higher iron levels in the brain, according to a study of almost 21,000 people publishing July 14 in the open access journal PLOS Medicine. Iron accumulation ...

Neuroscience

Neuronal processes involved in musical interactions

Making music together is a unique challenge: Not only must a musician plan and execute the sounds made by their own instrument, but they have to coordinate their actions with those of others. This is an extraordinary accomplishment ...

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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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