A new study has suggested that kids tend to blindly trust things told to them.
Previous research has found that three-year-olds are a credulous bunch; they believe most things they're told, and skepticism doesn't kick in until later.
Vikram K. Jaswal, of the University of Virginia and his students, A. Carrington Croft, Alison R. Setia, and Caitlin A. Cole, asked whether three-year-olds are more trusting of information they are told than the same information conveyed to them without words.
In one experiment, an adult showed children a red and a yellow cup, then hid a sticker under the red one.
With some children, she claimed (incorrectly) that the sticker was under the yellow cup; with other children, she placed an arrow on the yellow cup without saying anything.
The children were given the chance to search less than one of the cups and allowed to keep the sticker if they found it. This game was repeated eight times (with pairs of differently coloured cups).
The children who saw the adult put the arrow on the incorrect cup quickly figured out that they shouldn't believe her.
But the kids who heard the adult say the sticker was under a particular cup continued to take her word for where it was.
Of those 16 children, nine never once found the sticker.
"Children have developed a specific bias to believe what they're told," said Jaswal.
"It's sort of a short cut to keep them from having to evaluate what people say. It's useful because most of the time parents and caregivers tell children things that they believe to be true," he added.
The findings were published in Psychological Science, a journal of the Association for Psychological Science.