How you are feeling has an impact on your routine economic transactions, whether you’re aware of this effect or not.

In a new study that links contemporary science with the classic philosophy of William James, a research team finds that people feeling sad and self-focused spend more money to acquire the same commodities than those in a neutral emotional state. The team’s paper, “Misery is not Miserly: Sad and Self-Focused Individuals Spend More,” will be published in the June 2008 edition of Psychological Science and will be presented at the Society for Social and Personality Psychology’s Annual Meeting on Feb. 9.

The new study follows up on earlier research that established a connection between sadness and buying. Researchers Cynthia Cryder (Carnegie Mellon University), Jennifer Lerner (Harvard University), James J. Gross (Stanford University), and Ronald E. Dahl (University of Pittsburgh) have now discovered that heightened self-focus drives the connection — a finding that expands understanding of consumer behavior and, more broadly, the impact of emotions on decision-making.

In the experiment, participants viewed either a sad video clip or one devoid of human emotion. Afterward, participants could purchase an ordinary commodity, such as a water bottle, at various prices. Participants randomly assigned to the sad condition offered almost 300% more money to buy the product than “neutral” participants. Notably, participants in the sadness condition typically insist, incorrectly, that the emotional content of the film clip did not carry over to affect their spending.

Self-focus helps to explain the spending differences between the two groups. Among participants “primed” to feel sad, those who were highly self-focused paid more than those low in self-focus. Notably, sadness tends to increase self-focus, making the increased spending prompted by sadness difficult to avoid.

Why might a combination of sadness and self-focus lead people to spend more money?Â First, sadness and self-focus cause one to devalue both one’s sense of self and one’s current possessions. Second, this devaluation increases a person’s willingness to pay more for new material goods, presumably to enhance sense of self.

Notably, the “misery is not miserly” effect may be even more dramatic in real life, as the low-intensity sadness evoked in the experiment likely underestimates the power of intense sadness on spending behavior. The effect could extend to domains beyond purchasing decisions, causing people to engage in increased stock trading, for example, or even to seek new relationships– without conscious awareness that they are being driven by their emotions.

The study is an early step toward uncovering the hidden impact of different, fluctuating, and what would otherwise seem irrelevant emotions on our day-to-day decisions.

The paper is co-authored by a multi-disciplinary team of scientists. Cynthia E. Cryder, a doctoral student at Carnegie Mellon University, studies behavioral decision research. Jennifer S. Lerner, a professor at Harvard Kennedy School, specializes in the study of emotion and decision making. James J. Gross, an associate professor at Stanford University, studies emotion and personality. Ronald E. Dahl, a professor at the University of Pittsburgh Medical School, specializes in brain maturation and emotional functioning.