The Wikipedia article no longer makes reference to the
phenomenon that you quote (to my inspection), so I'm not
entirely sure if that assertion was edited out as an inaccuracy
on someone's part. I did find some information on visual
perception and high frequency flicker that might point to some
of the significance of the 60 Hz refresh rate of a monitor. At
first I thought the effect you were describing might have
something to do with critical flicker fusion frequency. This is
the rate under which the blinking of a light is no longer
perceived as continuous. For humans this varies from about 37 to
46 Hz (when measured as frequency of stimulus offset and
remeasured over the course of the year) and from 43 down to 36
Hz (when measured as a frequency of stimulus onset and
remeasured over the course of the year), so if a light blinks at
a rate higher than that, it will look like it is continuously on
to the average human.** However, since 60Hz is just shy of being
a harmonic for the human critical flicker fusion,