Mental-state reasoning is universal milestone in child development

On this boring Wednesday afternoon, nothing would entertain a young child more than to play a joke on the babysitter. The sitter always keeps her lunch in her purse; so when she leaves the room, the little prankster quickly hides it under the couch. When the babysitter returns, where will she look first? Whether from Canada or Thailand, 3-year-old children will most likely guess under the couch; it will not be until the ripe old age of 5 that they know that the babysitter will look for her lunch right where she left it.

A major social-cognitive achievement of young children is the understanding that other people act on the basis of their own representations of reality rather than on the basis of reality itself. Developmental psychologists have explored the refinement of mental-state reasoning in children, typically by measuring their ability to pass false-belief tasks, such as the example above. Yet previous research has only been conducted in Western cultures, where children pass such tests around the age of 5. New research reveals that children reach this false-belief milestone at about the same age the world over.

The findings appear in the report, "Synchrony in the Onset of Mental-State Reasoning: Evidence from Five Cultures," published in the May 2005 issue of Psychological Science, a journal of the American Psychological Society. Researchers Tara Callaghan, St. Francis Xavier University; Mary Louise Claux, Catholic University of Peru; Shoji Itakura, Kyoto University; Angeline Lillard, University of Virginia; Hal Odden, Emory University; Philippe Rochat, Emory University; Saraswati Singh, M.K.P. College; and Sombat Tapanya, Chiang Mai University, tested the false-belief understanding of children in Canada, India, Peru, Samoa, and Thailand.

The test group consisted of 267 children, approximately 50 from each country, ranging from 30 to 72 months in age. The false-belief task involved the following test: One experimenter hid a trinket such as a coin or a ring under one of three bowls. When the first experimenter left the room, the second one told the children they were going to play a joke, and hid the trinket under a different bowl. The children were then asked which bowl they thought the first experimenter would check when she returned. Children who pointed to the bowl that initially hid the trinket, as opposed to the trinket's new location, "passed" the test.

Results from all five countries revealed a shift from failure to success on this task between the ages of 3 and 5, revealing that it is a universal milestone in child development. "Synchrony in the age at which children of diverse cultures pass the false-belief task undermines the claim that particular cultural views, such as a Western concept of mind, profoundly influence this very basic aspect of early mental-state reasoning, and strengthens a claim of universality," the authors wrote.