"We had a lot of kids who were drinking not only soda, but coffee," she relates. "I had 12-year-old girls who said that all they had that morning was a cup of coffee. I started thinking -- 'This can't be good.'"
These findings led her to study how hard a person will work to obtain a particular food, or in this case, a caffeine drink -- and how food reinforcement mimics drug addiction. She is trying to understand the mechanisms that underlie such reinforcement, and if it can be redirected to a more healthy habit.
The just-published study on the reinforcing value of caffeine involved 26 boys and 23 girls ages 12-17. The participants, who were not aware the study was testing caffeine's reinforcement effects, were placed into groups based on their reported caffeine consumption, in any form.
Participants underwent a baseline test to determine if they could taste caffeine in the study drinks (they couldn't), and a run-through to familiarize them with the computer-based program they would be using in the experiment.
To give participants experience with the study drinks, they were sent home with a week's supply of test soda, randomized to be caffeinated or non-caffeinated, and were instructed to drink a 32-ounce bottle every day, for seven days, and no other soda or caffeinated products. During the second week, they obtained a week's supply of the opposite drink.
Participants then returned to a laboratory equipped with two computers, one on which participants played a computer game to earn caffeinated drinks and on the other, non-caffeinated drinks, although the drinks' caffeine status was blinded. The longer they played, the more difficult the game became.
Temple said the difference in the reinforcing potential of caffeine between males and females, but not between
|Contact: Lois Baker|
University at Buffalo