Summary: Researchers examined how young children begin to understand and use deception, tracking their thinking and behavior as they learn when and how to lie.
Source: The Conversation.
Lying carries clear costs for both the liar and those who are deceived. For the person who lies, maintaining a false story is mentally demanding: it requires keeping track of what was said, managing inconsistencies as real events intervene, and coping with the anxiety of being discovered. If exposure occurs, reputational harm can be lasting. For the targets of lies, deception damages trust, undermines relationships and weakens institutions.
At the same time, the ability to deceive can be a powerful social tool. Deception allows people to avoid responsibility, claim credit undeservedly, manipulate opinions, and gain allies. Because of its potential social impact, learning to deceive is an important milestone in childhood, and it depends on several cognitive capacities that must develop first.
Studying how children learn to deceive
Psychologists study early deception to understand why people sometimes choose to lie rather than tell the truth. Research approaches include observing children in experimental games where lying produces a material reward, placing them in polite social situations where a lie might be seen as more acceptable than blunt honesty, and asking parents to record everyday lies their children tell. Each method reveals different aspects of how and why children deceive.
In a recent study, researchers focused on the moment when children first discover that deceiving others can produce personal gain, a transition that usually occurs around three and a half years of age. The study also asked whether certain social experiences might accelerate that discovery and how individual differences in cognitive skills influence the pace at which children adopt deception as a strategy.
Watching children discover how to deceive
The research used a simple competitive game in which children could win treats only by deceiving an adult opponent. The setup was straightforward: a child hid a treat under one of two cups while the adult turned away and covered her eyes. When the adult reopened her eyes and asked where the treat was, the child could point truthfully (which gave the treat to the adult) or indicate the wrong cup (which gave the treat to the child).
Each child played 10 rounds of the game per day over 10 consecutive days. This intensive, short-term observation makes it possible to track small, rapid changes in behavior and to see the process of discovery as it unfolds, rather than relying on one-off tests or retrospective reports.
The study focused on children around their third birthday, a time when most are still only beginning to understand deception. At first, most children offered truthful responses and lost every round. Within a few sessions, however, many children realized that giving misleading information could win them the treat. After that initial discovery, children who had figured out the strategy used deception reliably in subsequent rounds.
Individual differences and underlying skills
Not every child learned to deceive at the same pace. Some understood the tactic immediately and began to lie on the first day; others continued to lose consistently even after the full 10-day sequence. The researchers examined factors that predicted how quickly children discovered deception and found two cognitive skills especially relevant.
First, theory of mind — the ability to appreciate that other people have knowledge, beliefs and perspectives different from one’s own — was important. Lying requires the child to recognize that the listener does not know the true location of the treat and can be misled. Second, cognitive control — the capacity to inhibit a truthful response and manage one’s own impulses — helped children resist blurting out the truth when deception was advantageous. Children who rose to deception most quickly tended to score higher on measures of both theory of mind and cognitive control.
These results suggest that competitive play can highlight deception as a useful strategy, but only once the relevant mental skills are in place. The discovery itself is only the beginning of a longer developmental path.
After children learn that deception can achieve goals, they must grapple with social and moral messages about honesty and falsehood. They also refine their deceptive abilities: very young children often betray themselves when they try to deceive by revealing truthful cues in words, facial expressions or body language. Over time, children learn to manage those cues more effectively and to use more subtle forms of influence, such as flattery, selective disclosure and conversational steering.
As children develop these abilities, they gain increasing power to shape social interactions and narratives. That influence can have wide-ranging consequences for their relationships and for the social environments in which they live.
Funding: Gail Heyman has received funding from the Chinese Foreign Expert Program.
Source: Gail Heyman, The Conversation.
Image source: Image adapted from the original research news release.