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Ball Lightning Caused By Magnetic Hallucinations
KentuckyFC writes "Transcranial magnetic stimulation involves placing a human in a rapidly changing magnetic field powerful enough to induce eddy currents in the brain. Focus the field in the visual cortex, for example, and the induced eddys cause the subject to 'see' lights that appear as discs and lines. Move the field within the cortex and the subject sees the lights move too. Physicists have calculated that the fields associated with certain kinds of multiple lightning strikes are powerful enough to induce the same kind of visual hallucinations in anybody unlucky enough to be within 200 meters or so. These fields ought to induce hallucinations that would take the form of luminous lines and balls that float in front of the subject's eyes, an effect that would explain observations otherwise classed as ball lightning, say the scientists."
Doesn't explain people having captured ball lightning on video from in some cases miles away.
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If these are equivalent to migraine auras, I'm very skeptical that they can explain ball lightning. I've periodically experienced migraines and what doctors assure me is an aura preceding it. I don't know about others' subjective experience with auras, but while it's an annoying visual artifact covering some or all of my visual field, at no point did I ever perceive it as some localized 'ball' with anything like a defined position, distance relative to me, etc. as ball lightning is often described. It was always something I perceived as an internal static that makes my vision mostly useless, not some external object.
Again, there could just be subjective difference, but I've never heard a fellow migraine sufferer describe an aura as some ball of light.
For those that suffer from migraines, these lights and balls should be familiar as "aura", or scintilating scotoma. For migraineurs, these lights last longer because they are caused by changing bloodflow to the occipital lobe over a longer period of time. It most assuredly activates the same neurons that this magnetic stimulation of neurons produces.
I would not be surprised of reports of concomitant parosmia, or olfactory hallucinations, with the display of ball-lightning caused by magnetic fields.