Dimming room lights may help you make more rational decisions

Researchers conducted a series of studies to examine the unusual paradox of lighting and human emotion, and found that emotion, whether positive or negative, is felt more intensely under bright light.

Alison Jing Xu, assistant professor of management at UTSC and the Rotman School of Management, conducted the study along with Aparna Labroo of Northwestern University.

"Other evidence shows that on sunny days people are more optimistic about the stock market, report higher wellbeing and are more helpful while extended exposure to dark, gloomy days can result in seasonal affective disorder," Xu said.

"Contrary to these results, we found that on sunny days depression-prone people actually become more depressed," she said, pointing to peaks in suicide rates during late spring and summer when sunshine is abundant.

Xu and Labroo asked participants to rate a wide range of things- the spiciness of chicken-wing sauce, the aggressiveness of a fictional character, how attractive someone was, their feelings about specific words, and the taste of two juices- under different lighting conditions.

They found that under bright lights emotions are felt more intensely. Xu said the effect bright light has on our emotional system may be the result of it being perceived as heat, and the perception of heat can trigger our emotions.

The majority of everyday decisions are also made under bright light. So turning down the light may help you make more rational decisions or even settle negotiations more easily.

The study was published in the Journal of Consumer Psychology.