While it may seem like a straightforward concept, formulating a hard-and-fast definition for an "imaginary friend" can be tricky. For one thing, kids aren't exactly known for being the most reliable self-reporting research subjects.
"Talking to a child about an imaginary companion, you have no idea what's going to come out," Tracy Gleason, Ph.D., a developmental psychologist at Wellesley College, told Science Friday. "They'll tell you something and you'll think 'what are they talking about?' We've said, 'do you have an imaginary companion?' and they'll think, 'what a great idea!' So, they'll say 'Yes. Yes, I do!' And they'll report on some imaginary companion they're making up right on the spot."
Typically, psychologists divvy up the broad category of imaginary friends into two groups: invisible pals and personified objects. "It's a made-up or unreal companion that typically provides comfort or support to a child," says Dr. Sheryl Gonzalez Ziegler, the founder and managing director of The Child & Family Therapy Center at Lowry in Denver. "When it's an invisible friend, it's typically more like, 'Annie is my pal and she goes everywhere with me and you can't see her, but I can see her.' There are also imaginary friends that are personified objects. So, like a teddy bear. The relationship there is usually a more caretaking style, but it doesn't have to be a doll — it can be anything."
But even these categorizations can get confusing. While some experts only consider invisible pals "imaginary," others are adamant that omitting the tangible object variety overlooks an important segment of fantasy friends (think stuffed animal Hobbes from the cartoon strip "Calvin and Hobbes")."Objects can be imaginary friends, too, because the child assigns animate qualities to an inanimate object," Ziegler says. "They believe that the objects can speak or move so that is why the term 'imaginary' may be assigned in this case."
And these objects aren't just limited to those found on toy store shelves. Gleason says she once heard about a child who formed a close relationship with a can of tomato paste, for instance [source: Groskin].
But marriage and family therapist Robin Walker of Valley Child Therapy in Woodland Hills, California, says most kids have an imaginary friendship to help them relate to others. "A psychologist named Donald Winnicott developed the idea of 'transitional space,'" he explains. "Winnicott said existence is about how we relate to each other — others in our life are our prime motivating force."
The problem, Walker explains, is that it's impossible to ever really be on someone else's level and relate to them completely. "The best way to do that is through transitional objects or transitional space," he says. "It's the gap between us that we can never quite bridge. We can both relate to it, and therefore, relate to each other."
Based on Winnicott's theory, Walker says an object like a teddy bear or, well, a can of tomato paste, can provide a meaningful connection between two people — or between children and the world. In some cases, transitional objects can even act as temporary substitutes for important figures. "They can create something that takes the place of their mother or father if one isn't there, or if [the child] has a sense of loneliness, they can always have the object and it's like having mom or dad," Walker says.