Stress triggers desire to indulge in rewards

Stressed people go to great lengths to satisfy their desire to indulge, such as running to a departmental store at midnight just to have a drink or sweets, shows a study.

"Stress plays a critical role in many psychological disorders and is one of the most important factors determining relapses in addiction, gambling and binge eating," said one of the study authors Tobias Brosch from University of Geneva in Switzerland.

"Stress seems to flip a switch in our functioning: If a stressed person encounters an image or a sound associated with a pleasant object, this may drive them to invest an inordinate amount of effort to obtain it," Brosch aded.

But the researchers also found that stressed people would not enjoy the reward more than anyone who is not stressed and has the same treat just for pleasure.

"Most of us have experienced stress that increases our craving for rewarding experiences, such as eating a tasty bar of chocolate, and it can make us invest considerable effort in obtaining the object of our desire," lead author Eva Pool, a doctoral student at University of Geneva, said.

"But while stress increases our desire to indulge in rewards, it does not necessarily increase the enjoyment we experience," Pool said.

In an experiment, researchers found that stress prompted chocolate lovers to exert three times as much effort to smell chocolate than unstressed chocolate lovers.

But both groups reported about the same level of enjoyment when they got a whiff of the pleasing aroma, the findings showed.

For the experiment, researchers recruited 36 university students, of whom 19 were men, who said they love chocolate.

The study appeared in the Journal of Experimental Psychology: Animal Learning and Cognition.