Stories
Slash Boxes
Comments

SoylentNews is people

posted by mrpg on Saturday February 17 2018, @08:01PM   Printer-friendly
from the signal-to-noise-ratio dept.

Diplomats and other victims of mysterious "sonic attacks" at the American embassy in Havana, Cuba are experiencing neurological symptoms months after being affected:

A preliminary case report on the victims of mysterious "health attacks" in Havana, Cuba details the results of extensive clinical evaluations, concluding that the individuals appear to have sustained "injury to widespread brain networks without an associated history of head trauma."

The report offers the first medical glimpse of the victims—US government personnel and their families who were serving on diplomatic assignment in Havana. From late 2016 to August 2017, they reported experiencing bizarre and inexplicable sonic and sensory episodes. The episodes tended to include directional, irritating sounds, such as buzzing and piercing squeals, as well as pressure and vibrations. Afterward, the victims developed a constellation of neurological symptoms.

In clinical evaluations of 21 of 24 individuals affected, an interdisciplinary team of doctors at University of Pennsylvania's Perelman School of Medicine retrospectively pieced together symptoms—an average of 203 days after individuals were exposed. They found that the most common issues persisting more than three months after exposure were cognitive impairment (17/21); balance issues (15/21); visual (18/21) and hearing (15/21) problems; sleep impairment (18/21); and headaches (16/21).

Previously: U.S. State Department Pulls Employees From Cuba, Issues Travel Warning Due to "Sonic Attacks"
A 'Sonic Attack' on Diplomats in Cuba? These Scientists Doubt It


Original Submission

 
This discussion has been archived. No new comments can be posted.
Display Options Threshold/Breakthrough Mark All as Read Mark All as Unread
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
  • (Score: 4, Informative) by ben_white on Sunday February 18 2018, @01:37AM (4 children)

    by ben_white (5531) on Sunday February 18 2018, @01:37AM (#639553)

    They sound like they are produced mechanically but they are not.

    Wrong. The sounds in an MRI scanner are mechanical in origin. They are from vibrations in the gradient coils when rapid changes in current are applied.

    Starting Score:    1  point
    Moderation   +2  
       Informative=2, Total=2
    Extra 'Informative' Modifier   0  
    Karma-Bonus Modifier   +1  

    Total Score:   4  
  • (Score: 1, Troll) by leftover on Sunday February 18 2018, @02:39AM (3 children)

    by leftover (2448) on Sunday February 18 2018, @02:39AM (#639568)

    Sorry but nope. They can not be heard by anyone outside the field. Very thoroughly investigated.

    --
    Bent, folded, spindled, and mutilated.
    • (Score: 0) by Anonymous Coward on Sunday February 18 2018, @06:18AM

      by Anonymous Coward on Sunday February 18 2018, @06:18AM (#639629)

      So wrong.

      I work with MRI every day and the noise is absolutely mechanical in origin and is heard by everyone in the vicinity. If you ever did the high-school experiment where you generate current in a wire by moving a magnet next to it then you have the explanation. The only difference in the MRI machine is that the current is changing in a static magnetic field.... which generates motion in the the wires surrounding the magnet cryostat, which creates the sound.

    • (Score: 3, Interesting) by tonyPick on Sunday February 18 2018, @10:54AM (1 child)

      by tonyPick (1237) on Sunday February 18 2018, @10:54AM (#639666) Homepage Journal

      They can not be heard by anyone outside the field

      Seriously, the first result on Google: http://www.nytimes.com/2012/04/17/science/why-mri-machines-make-that-loud-noise.html [nytimes.com]

      The pulses cause not just the desired changes but undesired vibrations of the gradient coils, resulting in the banging heard during an M.R.I. examination.

      As stronger magnets result in stronger vibrations, the higher the field strength of the M.R.I. scanner, measured in teslas, the louder the banging, Dr. Hentel said.

      On a side note: I've been in an MRI a couple of times, and you can hear them running from the adjacent waiting room.

      One time I got earplugs and the last time I had earplugs and headphones on me piping in local radio over them just to keep the noise down. Five more minutes of 90's pop and I'd have hit the damn panic button.

      • (Score: 2) by leftover on Sunday February 18 2018, @05:18PM

        by leftover (2448) on Sunday February 18 2018, @05:18PM (#639743)

        My source references were first-hand [unfortunately extensive] experience followed by discussions with engineers who did the testing under contract with the FDA. Perhaps early devices let some coils bang around but that could not have produced the high audio frequency components of the "clang" sounds I experienced. The closest I came to reproducing the sound mechanically used two pieces of cold-rolled steel bar, 3/8x2x36, whacked together crosswise on the 2" faces at approximately midpoint. The MRI sounds decayed much faster and varied with the machine settings Those BF coils would shrug off any signal at those frequencies so it does seem likely that the direct mechanism is microwave, as mentioned in an earlier post.

        Also, newer machines are really quiet mechanically but the clanging and banging are as loud as ever. Aside: The first device in my experience, in the early 1980s, had a bore diameter of 18" and was pretty rough in its mechanical movement. I had to stretch my arms above my head and offset my shoulders, couldn't inhale fully. Quite memorable.

        --
        Bent, folded, spindled, and mutilated.