A really good round up of the science behind the stories in today's papers on a new migraine magnet therapy.
Migraine magnet therapy - Behind the Head... - Healthy Evidence
Migraine magnet therapy - Behind the Headlines on today's story
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Bit of background for anyone with time on their hands:
Short abstract from a published paper:
ncbi.nlm.nih.gov/pubmed/239...
Note that transcranial magnetic stimulation (TMS) has also been used for the treatment of depressions and work has been carried out for other conditions such as Auditory Hallucinations
psychiatry.yale.edu/researc...
And of course, dear old Wikipedia:
Is it true that no one has evidence for how it works but that it just does? What are the most plausible theories?
I think (though I am guessing wildly) that this is coming out of the same draw as electric shock therapy. The magnetic side of this is a little misleading - from the physics point of view this is good old induction, making use of the relationship between magnets and electric currents; the magnets are stimulating the production of small electric currents in the brain. But unlike directly applying an electric shock, the effect is limited, only producing the currents in a small, immediate area around the magnets and limited in depth (to around 50mm or so). Consequently, this does not have the debilitating effect of controversial electric shock therapy - I doubt you feel a thing with this.
However, exactly what effect applying an electric current to a brain cell or to pathways has to any condition has mostly been described by results rather than physical evidence - a demonstration, perhaps, of how much we still have to learn about how the brain functions.
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Bit of info from the Migraine Trust website:
News Item: migrainetrust.org/news-new-...
NICE guidance: publications.nice.org.uk/tr...
Link to manufacturers patient information literature: migrainetrust.org/assets/x/...
Blog written by Dr Mark Weatherall (Migraine Trust trustee): migrainetrust.org/news-new-...