These manipulations may have been employed for good or bad, as an attention getting device, or to take focus off one's immediate mind-set. Examples range from police officers who caught speeders but didn't see that open beer can in the back seat. Sense merely blinking can do this, and when people blink they usually miss floaters, blinking has not been solicited as it should. People like quietness and verbal communication goes on without speaking.
Sleep is also a means of relating to the blink.
What we want to see in the next few paragraphs is the relationship between blinking, cognizance, and light. While doing this, one must make anywhere from the smallest impetus to an impact upon the other's conscious. So the teaser must elect to have at least one photon of light to find an unexpected place, or an unusual method, to carry through the tease. Being cognizant of any sudden event naturally acts as a mental shock-boost depending upon the degree of startling. This seems to be what happens a great deal when blinking at another.