Experimenter effects on children's understanding of false drawings and false beliefs.

Two experiments were conducted in which a variant of J. McGarrigle and M. Donaldson's (1975) "Naughty Teddy" intervention was applied to children's understanding of false drawings and false beliefs. The results showed that preschool children's understanding of the contents of an out-of-date drawing improved when the drawing was made by a capricious agent ("Naughty Snakey" glove puppet) rather than by the experimenter. The children's performance on a false belief task also improved when the events that set up the false belief were the result of the actions of the glove puppet. The results are discussed in terms of the role of children's sensitivity to the pragmatics of interactions in their development of a theory of mind.