Six-month-old babies might not be able to express themselves with words, but a new study has found they know when you're teasing them - and they don't appreciate it.
Researchers at Toronto's York University examined six- and nine-month-old babies' reactions to a game in which an experimenter was either unable or unwilling to share a toy.
They found the babies could tell and "calmly accepted" when an experimenter was unable to share the toy for reasons beyond his or her control.
However, the babies averted their gazes and became agitated when it was clear the experimenter simply wouldn't share the toy.
"Babies can tell if you're teasing or being manipulative, and they let you know it," said lead author Heidi Marsh. "These results are exciting, as it's the first demonstration that used infants' social behaviour to successfully show that at six months, they comprehend the goals of our actions."
The study also found six-month-olds have a different way of expressing this awareness than nine-month-olds. The latter often banged their arms when the experimenter was intentionally withholding the toy, whereas the six-month-olds were more likely to frown.
The experimenters also used facial expressions to help convey whether they were unwilling or unable to share the toy.
Forty infants, including 20 boys and 20 girls, and their mothers participated in the study, called Six-and Nine-Month-Old Infants Discriminate Between Goals Despite Similar Action Patterns.
