RSS Feed

A Trusted Agent (3 years)

**How children strongly trust what people tell them**

Can children resist the urge to trust what adults tell them?  When can they suspend belief in others and change their behavior accordingly?  Jaswal et al. (2010) examined whether children have a strong inclination to believe what others tell them.  In the study, the researchers had children participate in different conditions which, when compared, tested their hypotheses.  Below, I’ll describe the mechanisms of the “testimony” condition which shows the strong effect of children’s trust in spoken testimony when searching for something desirable: a sticker.


  •  8 stickers
  •  Two plastic cups of different colors (e.g., red and blue) that the stickers can be hidden beneath
  •  A tray where the cups can be placed upside-down
  •  A piece of cardboard large enough to conceal your hands while hiding stickers under the cups but not so large that your shoulders and face are concealed
  •  A confederate (e.g., a family friend) who can provide the testimony


Ask the confederate to sit at a table across from the child.  Start by explaining to the child that she’s going to play a game where she tries to find a sticker hidden under the cups.  If the child finds the sticker in the first cup she looks under, she gets to keep it – otherwise the confederate does.  He also tells the child, “I’m going to try to get as many stickers as I can! How about you?”

Start by placing the two cups on opposite ends of the tray and then position the cardboard screen to hide the confederate’s hands as he places the first sticker under one of the cups behind it.  He then lifts the screen and says that the sticker is hidden in the cup opposite to where it’s actually hidden; if it’s under the blue cup, he says:  “it’s in the red cup.” Next, push the tray toward the child and allow her to search under one cup. If she chooses the cup that was indicated, the incorrect cup, she will not find the sticker and the confederate can show her where it is and then keep it. If she chooses the correct cup, she can keep the sticker she finds.

This game continues for 8 trials; mix up whether the sticker is actually on the right or left so that it’s balanced. You can keep track of which cup the child chooses each time. Don’t worry, the child can have all of the stickers at the end (and even one occasionally during the game if he’s getting frustrated!).

Notes & Observations

What did you observe? Did your child search under the indicated cup the first time?  What about the subsequent trials?  Did he come to a realization about your “trickiness” and change course?

Research Findings & Extension

The researchers found that, naturally, all children looked under the cup that was indicated (“it’s in the red cup”) on the first trial.  Surprisingly though, children did not quickly realize that they should not trust what the experimenter said – many children did not find a single sticker over 8 trials!  In the study, a second condition was used called the “arrow” condition where the adult indicated which cup held the sticker by placing an arrow on it (children were trained to use this as a cue) but did not say anything.  In contrast, in that condition, children quickly realized that they should not trust the arrow’s location and found many more stickers.  The researchers argued that children’s belief in verbal testimony is so entrenched that it is difficult for them to inhibit responding to it (whereas they are not accustomed to trusting the arrow).  This sort of trust in the adults around them would be adaptive for infants and children since they have no other source for helpful information and would become stronger over time as it’s reinforced. By age 4, children do not show this same persistent trust.


Jaswal, V.K., Croft, A.C., Setia, A.R., & Cole, C.A. (2010). Young children have a specific, highly robust bias to trust testimony. Psychological Science, 21, 1541-1547.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: