&quot;I was driving at night and saw the indicator LED on my phone flashing blue out of the corner of my eye. When I stopped and checked it, it turned out that it was actually yellow.&quot;<p>I quite often have a similar experience...<p>I always put my phone on my desk just below my monitor - just at the edge of my field-of-view.  My phone has an LED that flashes green when I have an SMS and red when I have a missed call or low battery (both with the same cadence).  If I&#x27;m focussed on the monitor, I can see the light flashing but until I look at it, it appears to be flashing white (presumably because I have very few cones at the edge of my field-of-view).<p>Even more interestingly, once I have looked at it, determined whether it&#x27;s red or green, and then return my eyes to looking at the monitor, I can still see it flashing at the edge of my field-of-view, but now my brain fills in which color it is - I now see it flashing red or green (despite there still being no cones to detect this).<p>I think it&#x27;s amazing how of my perception of the world is actually filled in by my brain rather than &quot;raw data&quot;.