A Heart-Wrenching Epidemic
What happened to Juan that day -- death by hyperthermia, caused when the body's temperature rises uncontrollably -- has happened to about 450 children in the U.S. since 1998. "It's reasonable to call this an epidemic," says memory expert David Diamond, Ph.D., a scientist at the Veterans' Hospital in Tampa, who is often consulted on such cases. "It happens, on average, once a week from spring to early fall." Babies and young children are not able to regulate their body temperatures well -- warming at a rate three to five times faster than an adult -- especially in a car, where the windows create a greenhouse effect. In just half an hour, a car's interior can get 35 degrees hotter. Depending on such factors as what color he's wearing and when he last drank something, an infant might die of hyperthermia in just 15 minutes on a 75-degree day. Cooler weather is no guarantee of safety, either. Overly bundled babies -- warmly dressed and blanketed in their car seats -- have been known to succumb when outdoor temps were in the 60s or even 50s. And despite popular belief, cracking open a window does little good. That tiny bit of air can't begin to offset the heat that is absorbed by a car's seats, dashboard, and walls.
Some children are knowingly and negligently left inside hot vehicles while their parents do errands. Other kids climb inside their parents' parked cars and become trapped. But most, like Juan Parks, are victims of adults' disastrous lapses in memory. "Given the right scenario, I would say this can happen to anyone," says Diamond. "It has nothing to do with how much parents love their kids. It is, to me, a tragic way of learning how the brain works."
Each of us has dueling memory systems, Diamond explains. The first -- in the primitive, "reptilian" part of the brain -- directs our habits. It's the system that lets you drive home from work without thinking consciously about every turn. The second system -- located in more advanced brain regions -- is responsible for short-term plans, such as "Buy milk on the way home." And as anyone who has ever forgotten that milk knows, the primitive "habit system" is much more powerful. "It's very difficult to keep in your mind that you want to override your habit system," Diamond says. "And it can take over almost immediately."