Jacques Vallee puts forth an interesting theory that alien abduction is merely a contemporary set of trappings to explain an age-old phenomenon: connection to an other-race from an other-place.

a hundred years ago, this phenomenon was known as faery abduction. The zeitgeist alters the details: in the modern age little green men or slender grey men from the hills are replaced by little green men or slender grey men from outer space...the erotic encounters with beings from faery are replaced by anal probes and fertility experiemnts conducted in alien ships. The slowing or halting of the passage of time, the sensation of floating, the bright lights: these are common to both.

Other cultures have other explanations...

Peg