The findings showed that people often find themselves drawn to individuals after multiple encounters, even when there was no initial attraction.
"Cupid's arrow is often slow to strike. It may be attributable to the gradual change in attractiveness from repetition," Ravi Thiruchselvam, Psychologist at Hamilton College in New York, was quoted as saying by dailystar.co.uk on Sunday.
For the study, the team gave snaps of people's faces to a group of young men and women.
The researchers then wired the participants brains to monitors as the group ranked the attractiveness of people in the pictures.
The subjects were then shown the snaps for a second time, and rated those they found attractive much more highly.
The attraction was even stronger on the third occasion and strongest of all on the fourth.
The fourth attempt showed extra activity around the excitement and pleasure centres of the brain of the participants.