Obese kids likelier to have slower cognitive function

Researchers have found that obese children are slower than healthy-weight children to recognize when they have erred and correct it.

Charles Hillman, a University of Illinois professor of kinesiology and faculty member in the U of I's Division of Nutritional Sciences, said that she likes to explain action monitoring this way: when you're typing, you don't have to be looking at your keyboard or your screen to realize that you've made a keystroke error, asserting that's because action monitoring is occurring in your brain's prefrontal cortex.

In the study, the scientists measured the behavioral and neuroelectric responses of 74 preadolescent children, half of them obese, half at a healthy weight. Children were fitted with caps that recorded electroencephalographic activity and asked to participate in a task that presented left- or right-facing fish, predictably facing in either the same or the opposite direction.

Children were asked to press a button based on the direction of the middle (that is, target) fish. The flanking fish either pointed in the same direction (facilitating) or in the opposite direction (hindering) their ability to respond successfully.

A second evaluation measured electrical activity in the brain "that occurs at the intersection of thought and action," Hillman said. "We can measure what we call error-related negativity (ERN) in the electrical pattern that the brain generates following errors. When children made an error, we could see a larger negative response. And we found that healthy-weight children are better able to upregulate the neuroelectric processes that underlie error evaluation.