BMI of San Diego built several liquid helium cooled SQUID-based sensors and image processing systems plus double-walled chambers with inflating doors for mapping brain magnetic activity. Scrips of La Jolla had one, and the systems worked rather well, but MRI stole their thunder at the time. This was many years ago & I have not kept up with it since.
Mike Harris/Teccom -----Original Message----- From: Robert Macy <[email protected]> To: Robert Tims (EMX) <[email protected]>; [email protected] <[email protected]> List-Post: [email protected] Date: Tuesday, January 25, 2000 12:23 PM Subject: Re: Magnetic field immunity in the Arctic regions > >Bob, > >Researchers are trying to use them to 3 dimensionally map the activity >(current flowing) in the brain. It is my understanding that the work is >going very slowly because this puts them right at the noise floor of SQUIDs. > >Human beings barely affect the earth's field, plus in an outside environment >the earth's magnetic field is too energetic in comparison to the human body >to be able to see the body. > > - Robert - > >PS Last comment ON the newsgroup to this unrelated topic. > >However there may come a day when we'll have to meet "Quiet Room" specs to >be used for mapping electrical brain activity. And those specs are going to >make a chamber look like a sieve. > >-----Original Message----- >From: Robert Tims (EMX) <[email protected]> >To: 'Robert Macy' <[email protected]> >Date: Tuesday, January 25, 2000 9:40 AM >Subject: RE: Magnetic field immunity in the Arctic regions > > >>Hey, >>can those things detect a human's effect on the magnetic field (or even a >>human's own magnetic field)? Would make a nice Search and Rescue tool if it >>did, for avalanches or earthquakes or whatnot, or even a good weapon! >>BR, >>Bob Tims >>Compliance Engineer >> >>> -----Original Message----- >>> From: Robert Macy [SMTP:[email protected]] >>> Sent: Tuesday, January 25, 2000 11:42 AM >>> To: Tom Cokenias; Peter Poulos; [email protected] >>> Subject: Re: Magnetic field immunity in the Arctic regions >>> >>> >>> Don't need SQUIDs to read earth's field. Fluxgates have enough accuracy. >>> And the earth's natural noise floor is well above the SQUID so you don't >>> need to pay for all that extra. Remember, SQUIDs can observe the current >>> flow as metal rusts. >>> >>> Check out Geometrics. They use the decay of the electron orbits in a >>> Cesium >>> atom (I think) to read magnetic field to 12 digits, yes that's 12 decimal >>> digits. I watched the readings shift as a greyhound bus drove by >>> deflecting >>> the earth's magnetic field over a city block away. >>> >>> - Robert - > > > >--------- >This message is coming from the emc-pstc discussion list. >To cancel your subscription, send mail to [email protected] >with the single line: "unsubscribe emc-pstc" (without the >quotes). For help, send mail to [email protected], >[email protected], [email protected], or >[email protected] (the list administrators). > > --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to [email protected] with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to [email protected], [email protected], [email protected], or [email protected] (the list administrators).
