[HN Gopher] New Nano-Tech to Control the Brain Using Magnetic Fi...
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       New Nano-Tech to Control the Brain Using Magnetic Fields
        
       Author : dockimbel
       Score  : 44 points
       Date   : 2024-07-20 08:32 UTC (14 hours ago)
        
 (HTM) web link (www.ibs.re.kr)
 (TXT) w3m dump (www.ibs.re.kr)
        
       | superkuh wrote:
       | >selective expression of nano-magnetoreceptors in specific
       | neuronal types and brain circuits and activating them with
       | rotating magnetic fields at precise moments, allowing for
       | spatiotemporal control of neural activity.
       | 
       | So invasive genetic engineering used to express the magnetically
       | sensitive (instead of light or ultrasound or whatever) ion
       | channels in the neuronal populations of choice.
       | 
       | Cool stuff, another tool, but there is a way to directly control
       | brains using only magnetic fields and no invasive genetic
       | engineering: transcranial magnetic stimulation. It's where a
       | very, very, very fast changing magnetic field induces a voltage
       | in a tissue. The rate of change of field being proportional to
       | the induced voltage. Generally this means ramping up from 0 to
       | ~5000 amps in a small magnetic coil in less than 10 ms.
       | Unfortunately TMS is not very focal and engineering limits mean
       | the effected tissue regions are about ~5-10 mm spheroids in
       | general (with a slow fall off over large scales); too big for
       | mouse models but fine for humans.
        
         | action-k wrote:
         | how safe is TMS - has that been studied?
        
           | superkuh wrote:
           | It has been studied widely in both research and clinical
           | practice for almost 40 years but most extensively since ~1990
           | to now. With repetitive TMS (rTMS) there are very small
           | chances of inducing a seizure if say, the patient has
           | temporal lobe epilepsy, but it is generally considered a very
           | safe procedure. And there are well established
           | intensity/repetition frequency limits for such cases defined
           | by stimulation region. It is even done in psychiatric (non-
           | hospital) settings. See chapter 5 for more information: http:
           | //erewhon.superkuh.com/library/Neuroscience/Magnetic%20...
           | (Magnetic stimulation in clinical neurophysiology / Mark
           | Hallett and Sudhansu Chokroverty. 2nd ed, 10MB PDF)
        
           | paulhart wrote:
           | I was a research subject for a TMS study a few years ago (I
           | made myself eligible by way of a bicycle accident). Having
           | your thumb twitch because the researcher "shot" magnetic
           | fields at my brain was an amusing experience; she said some
           | people completely freak out at it.
        
       | mapt wrote:
       | Nope.
       | 
       | Headline misleading.
       | 
       | You can tell from background, because strong magnetic fields take
       | an immense amount of power and space, and TMS & MRI magnets
       | beyond 1 Tesla are the size and weight and density of an anvil.
       | Nothing nano about magnets. Nanotech interacting electrically,
       | sure, but nanotech interacting with living tissue magnetically is
       | ludicrous.
       | 
       | Reading the actual article:
       | 
       | It isn't nanotech, it isn't controlling "the brain", it's testing
       | a brain specifically genetically engineered to express
       | magnetically sensitive control/sensory input sites that a TMS can
       | target selectively.
        
       | obrix wrote:
       | The headline reminded me of the Vernor Vinge book A Deepness in
       | the Sky.
        
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       (page generated 2024-07-20 23:14 UTC)