The Alien vs. Predator series of films provide a rare exception to the usual rule that fictional worlds are separate, with pretend entities in one not existing in any other. In 2006, Deena Skolnick and Paul Bloom showed that young children aged between three and six years already understand this idea well. For example, the children said that the comic hero Batman could touch his side-kick Robin, but couldn't touch the sea sponge cartoon character SpongeBob. Now Weisberg (nee Skolnick) and Bloom have built on these findings, showing that young children also keep fictional game worlds separate when they are playing.
An initial study involved 50 three- and four-year-olds. Each child sat with two experimenters, a toy bear, a toy doll and a central pile of toy blocks. The first experimenter, located to the right, introduced the child to the doll Mary; together they pretended it was her bath-time and the child used one or more blocks as bath objects, such as soap. Then the second experimenter, located to the left, introduced the child to Bruno the bear. They pretended it was his bedtime and the child used one or more blocks in the game, for example as a pillow.
The crucial part came next, as the first experimenter told the child that Mary had grown tired and needed to sleep, whilst Bruno had woken and wanted to wash. Rather than using the toy block already established to be a pillow in Bruno's world, the children, regardless of age, nearly always reached for a new block from the pile to use as a pillow for Mary. Similarly, rather than using Mary's soap, most children reached for a new block to use as soap for Bruno. This remained the case in a follow-up study in which the researchers took great effort to ensure the children understood that the objects in one game world were available, and no longer being used by another toy character.
"Just because something was a pillow in Bruno's world did not necessarily mean that it was a pillow in Maggie's world," the researchers said.
Concerned that the parallel play arrangements of the first two studies were unnatural, the researchers also performed a third and final study where two games were played in sequence. This time, if the researcher announced between game sessions: "I'm bored, let's play something else" the children were far less likely to transfer pretend objects from one game to another compared with an alternative situation in which the researcher merely said they should take a break between play sessions. In other words, the children seemed to understand when the researcher intended that they create a new fictional world.
"The results from these three studies suggest that children keep different pretend play games separate from each other, imposing subtle structure on their make-believe worlds," the researchers said.
Skolnick Weisberg, D., & Bloom, P. (2009). Young children separate multiple pretend worlds. Developmental Science, 12 (5), 699-705 DOI: 10.1111/j.1467-7687.2009.00819.x