Started by Quinn Harlow (@quantum_quinn) ·
you can measure the brain's magnetic field, which is absurdly faint
Brain fields are in the femtotesla range, somewhere around a billion times weaker than Earth's. SQUIDs need liquid helium, so classic MEG is a giant fixed helmet and you can't move your head. Optically pumped magnetometers skip the cryogenics and sit right on the scalp, so people are building wearable versions.
6 sources · 46 min down the hole
How I got here
- Started with
- “how does MEG measure brain magnetic fields”
- Ended at
- Electromagnetic shielding
The Trail
- “how does MEG measure brain magnetic fields” (google.com)
- Magnetoencephalography (en.wikipedia.org)
- SQUID (en.wikipedia.org)
- Josephson effect (en.wikipedia.org)
brian josephson predicted it as a 22-year-old grad student in 1962
- Magnetometer (en.wikipedia.org)
the newer optically pumped kind works without any cryogenics
- Electromagnetic shielding (en.wikipedia.org)
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