The brain’s sweet spot

By HSC Staff Writer • Published: March 27th, 2006
Category: Health in a Heartbeat

Human taste buds sure seem biased toward sweet foods. How else can you explain the popularity of dessert, which ensures an entire meal ends on a sugary note?

Experts know people crave sweets partly because some part of the brain’s appetite-control creates pleasurable sensations when we consume sugar.

But until recently it was unclear just where this reward system might be headquartered.

In a study published in The Journal of Neuroscience, University of Michigan researchers found that for rats, the good feelings originate from a tiny structure in the appetite-control center.

The reward system operates by releasing natural opiates. So to pinpoint the system’s location, researchers used a chemical that stimulated opiate release.

By injecting minute amounts of the chemical and measuring brain responses indicating pleasure, they found the structure. Turns out it’s cube-shaped and measures about one millimeter on each side.

When activated, it caused rats’ enjoyment of sugar to double, triple, even quadruple. The researchers also found the reward system operates separately from the appetite-control center.

If the human brain has a similar structure… and if it can be activated by other foods, as scientists believe… further study could lead to new treatments for eating disorders.

Anorexic patients might be motivated to eat normally if the reward system were activated at mealtime.

For the rest of us, perhaps it’s enough to understand a little better why we want that second dish of butter pecan ice cream. Not to mention the hot fudge.