Effect of electric toothbrush on Visual Perception

[Ron Blue]

On 1 Jun 1996, Michael Gillespi Steele wrote:
> Maybe some of you neuroscience folks can answer me this one:
> 
> As I was brushing my teeth with an electric toothbrush, I happened to
> look obliquely at my computer monitor screen and noticed that while I
> was doing this the screen seemed to flicker or vibrate.  Only the
> screen.  
>>>CUT>>> 
> My guess is that the sensation of the toothbrush on my teeth does
> something to my visual perception.  I realize that a computer screen,
> like a TV set is essentially a fast strobe light.   Is there a name for
> this, or am I having a seizure?
> 
> -Mike
> MikeG994 at ix.netcom.com
Mike, you are not having a seizure.  The viberation of
the toothbrush and the viberation of the 24 hertz display on the monitor
overlapped into a phase shift that appears to flicker or create a strobe
light effect.  You can get similar effect by running on a treadmill
get off quickly and look at the wall and see the wall going forward.
Ron Blue