Researchers say people who have negative emotions without knowing their source often allow the emotions to affect decisions on unrelated issues.
"When we do not know the cause of our negative states -- referred to as mood states by psychologists -- we use the moods themselves as information about our environment," explain Rajagopal Raghunathan of the University of Texas-Austin, Michel Pham of Columbia University and Kim Corfman of New York University.
They demonstrated the effect by putting subjects into a sad, anxious or neutral mood, then having them make choices unrelated to the source of their feelings. While both anxiety and sadness exerted a strong influence on decision-making, different types of negative emotions encouraged different choices.
"While anxiety triggers a preference for options that are safer and provide a sense of control, sadness triggers a preference for options that are more rewarding and comforting," write the authors.
Even when subjects identified the cause of the emotions, decisions moderately or superficially related to that cause were still affected by the emotions.
The study appears in the March issue of the Journal of Consumer Research.
Copyright 2006 by United Press International
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