My friend Karen says her son Christopher's devotion to garbage trucks began when he was around 18 months old. He would go nuts whenever he saw one. Karen tried to turn his attention to toy trains since that's what they had in the house, but he wouldn't have it. Garbage trucks. That was it.
And so Karen went with it. On Monday mornings, they'd hear the familiar rumble and go - she'd strap Christopher into his carseat, turn on the engine, and follow the shiny green truck marked Waste Management. The toddler would hand out granola bars and water bottles to the drivers, and watch them work ("They were celebrities to him," Karen says). All day, he would talk about garbage trucks, draw pictures of garbage trucks, and watch videos about garbage trucks ("He learned all the different types," Karen says. "There are front loaders, side loaders, back loaders.") On his birthday, Christopher had a garbage truck cake. For Halloween, he dressed as a garbage truck. On Christmas, he got new shirts and PJs with garbage trucks on them. Karen stops there. "This sounds so crazy, I know," she says.
It actually doesn't. Very specific obsessions are common in children - scientists call them "intense interests". Kate Morgan writes about the phenomenon in the New York Magazine piece "A Psychological Explanation for Kids' Love of Dinosaurs", citing that almost a third of all children have an obsession like this at some point, typically between the ages of two and six. More than fleeting kid-thrills, such as chocolate ice cream for dessert, these fascinations emerge without parental encouragement, stick around for a relatively long period of time (in child-years, that is), and are pursued with fervour, often to a point where people beyond Mum and Dad start to notice. The subjects of interest can range from garbage trucks to excavators to this personal injury lawyer from New Orleans. According to a Yale study, boys have intense interests much more commonly than girls.
And it's healthy, experts say. Gaining mastery in a single subject builds confidence, and Morgan found that it has other intellectual benefits, too. She writes:
A 2008 study found that sustained intense interests, particularly in a conceptual domain like dinosaurs, can help children develop increased knowledge and persistence, a better attention span, and deeper information-processing skills. In short, they make better learners and smarter kids. There's decades of research to back that up: Three separate studies have found that older children with intense interests tend to be of above-average intelligence.
Parents should do what they can to support their child's interest, even if it isn't their own cup of tea. One mum in the Yale study told researchers that her five-year-old daughter had "an extremely unusual interest in bodies and injuries", and so she would sometimes, reluctantly, agree to stop the car so they could examine road kill. (Props to that mother.) Bloody animals aside, losing yourself in a passion is a great joy, and parents can show their kids early on that there's always more to learn.
The obsessions often wane eventually, and that can be bittersweet. In the Yale study, when researchers followed up with parents, they reported that the interests lasted between six months and three years. As they grow up, kids develop other interests, and the nature of school makes it difficult to focus on just one subject.
But Christopher is six now, and he still wants to be a garbage man when he grows up. That, and an NBA player. But he can't do both on the same day because, he says, "they would think I'm too stinky."