Some babies grasp art of deception even before their first birthday, study says

Some are skilled in sneaky tactics such as exaggeration, denial, pretending not to hear an adult speak or hiding things by the time they are toddlers, researchers said. About a quarter of children start to understand deception by 10 months, rising to half at 17 months, according to the findings in the University of Bristol-led study.

By the age of three, children become more proficient, creative and frequent fabricators, the study claimed.

Elena Hoicka, a Bristol University professor of education and the study’s lead author, said: “It was fascinating to uncover how children’s understanding and usage of deception evolves from a surprisingly young age and builds in their first years so they become quite adept and cunning ‘little liars’.”

Parents of more than 750 children aged up to 47 months from the UK, US, Australia and Canada were asked about their child’s deception development. The youngest child deception was seen in an eight-month-old baby, according to a parent. Sneaky habits were also found to be frequent and 130 parents reported children engaged in 16 deception types before 47 months.

These included pretending not to hear to avoid answering or doing something, and also hiding things so others cannot have them, which was used by children who did not want to share their toys.

Denial, doing forbidden activities in secret, making an excuse, exaggeration and understatement were also among the deceptions used. Pretending not to know something even if they were actually aware of it or pretending not to understand was sometimes the response when a child was asked to help with a chore.

Fabrication by simply inventing something, pretending not to see when they are not supposed to be looking at something, withholding information and omission were other sneaky skills.

Children also deceived by restructuring responses by keeping just some parts of the truth in their answers but changing other elements. Being vague by leaving out details on purpose and also distraction was also a useful deception tool, the researchers found.

Prof Hoicka said: “From two years, deception tends to be action-based, or require only basic spoken responses, like pretending not to hear their parent say ‘time to tidy up’, hiding things from others, or denial – such as eating chocolate but shaking head to say ‘no’ when asked if they ate chocolate.

“It could also extend to doing forbidden activities in secret, for example looking in a bag they were told not to look in when no-one is apparently watching or making excuses, such as claiming to need the toilet, when asked to tidy up.”

Researchers believe the study will be useful for parents and educators, and provides insights into how children might later learn to deceive in more advanced ways as they get older.

Prof Hoicka said: “Firstly, parents can be reassured deception is entirely normal in toddler development.

“They can also look at our findings to know which types of deception to expect by age, so they can better understand and communicate with their children in order to stay one step ahead of their deceit.”

Study co-author Jennifer Saul, professor of philosophy at the University of Waterloo, said: “Philosophers have long reflected on the morality of human deception, but always focused on adults deceiving one another.

“This study shows just how much complexity gets overlooked by that focus.”