Social expectations reverse the effects of acetaminophen on economic decision-making

Research Projects

Organizational Units

Journal Issue


On an average week, 23% of the US population takes acetaminophen (i.e. paracetamol; active ingredient in Tylenol; Kaufman, Kelly, Rosenberg, Anderson, & Mitchell, 2002). Originally viewed as just a physical pain killer, acetaminophen has been shown to affect other psychological processes (DeWall et al., 2010; DeWall, Chester, & White, 2015; Durso, Luttrell, & Way, 2015; Randles, Heine, & Santos, 2013). With such a large proportion of the population routinely taking acetaminophen, it is critical to know how it might affect social and economic outcomes. Here we used a battery of economic games to demonstrate that acetaminophen has consistent effects on decision-making, but the direction of acetaminophen’s effect depends on whether the individual has high or low expectations. In a monetary investment game (i.e. trust game), acetaminophen increased investments from subjects with low expected returns from the trustee, but decreased investments from subjects with high expected returns. Next, in a negotiation game (i.e. ultimatum game), we used sequences of high and low monetary offers to exogenously manipulate the expectations of the responders. Acetaminophen increased the acceptance of relatively unfair offers and reduced the acceptance of relatively fair offers. Finally, acetaminophen also caused trustees in the trust game to be less influenced by their beliefs about how much the investors expected them to return. Thus, acetaminophen also reduced how beliefs about another’s expectations drove reciprocity. Overall, our results demonstrate that acetaminophen has socially important but previously unrecognized dampening effects on how people respond to both financial incentives and disincentives for themselves and for others. Furthermore, our findings highlight what we believe to be a general principle of drug action: that psychological factors can change the behavioral and perhaps clinical effects of drugs.


Social and Behavioral Sciences; Social Work; Law: 1st Place (The Ohio State University Edward F. Hayes Graduate Research Forum)


social neuroscience, psychology, acetaminophen, decision-making