It takes only a tiny magnetic field to see clear through a person’s head, a new study shows. A method called ultra-low field magnetic resonance imaging (MRI) has captured its first, blurry shots of a human brain, revealing activity as well as structure.
MRI scanners image the human body by detecting how hydrogen atoms respond to magnetic fields. They typically require fields of a few tesla—about 10,000 to 100,000 times stronger than the Earth’s magnetic field. The powerful magnets necessary make scanners pricey and also dangerous for people with metal implants.
The new device hits a sample with a 30 millitesla magnetic field, about 100 times weaker than is normally used in MRI. The device then uses a 46 microtesla magnetic field—about the same as the Earth’s magnetic field—to capture images of the sample.
The first target for the device was the head of lead researcher Vadim Zotev of Los Alamos National Laboratory in New
A. 10,000 to 100,000 times stronger than the Earth’s magnetic field.
B. 100 times weaker than the Earth’s magnetic field.
C. 100 times weaker than is normally used in MRI.
D. the same as the Earth’s magnetic field.
It takes only a tiny magnetic field to see clear through a person’s head, a new study shows. A method called ultra-low field magnetic resonance imaging (MRI) has captured its first, blurry shots of a human brain, revealing activity as well as structure.
MRI scanners image the human body by detecting how hydrogen atoms respond to magnetic fields. They typically require fields of a few tesla—about 10,000 to 100,000 times stronger than the Earth’s magnetic field. The powerful magnets necessary make scanners pricey and also dangerous for people with metal implants.
The new device hits a sample with a 30 millitesla magnetic field, about 100 times weaker than is normally used in MRI. The device then uses a 46 microtesla magnetic field—about the same as the Earth’s magnetic field—to capture images of the sample.
The first target for the device was the head of lead researcher Vadim Zotev of Los Alamos National Laboratory in New
A. The one by Vadim Zotev group with a single SQUID.
B. The one by Vadim Zotev group with seven SQUIDs.
C. The one by John Clarke group with a single SQUID.
D. The one by John Clarke group with seven SQUIDs.
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