Happiness and Stereotypic thinking in social judgment, Journal of Personality and Social Psychology
Four experiments examined the effects of happiness on the tendency to use stereotypes in social judgment. In each experiment, individuals who had been induced to feel happy rendered more stereotypic judgments than did those in a neutral mood. Experiment 1 demonstrated this phenomenon with a mood induction procedure that involved recalling life experiences. Experiments 2 and 3 suggested that the greater reliance on stereotypes evident in the judgments of happy individuals was not attributable to cognitive capacity deficits created by intrusive happy thoughts or by cognitively disruptive excitement or energetic arousal that may accompany the experience of happiness. In Experiment 4, happy individuals again were found to render more stereotypic judgments, except under conditions in which they had been told that they would be held accountable for their judgments. These results suggest that although happy people's tendency to engage in stereotypic thinking may be pervasive, they are quite capable of avoiding the influence of stereotypes in their judgments when situational factors provide a motivational impetus for such effort.
Bodenhausen, Galen. 1994. Happiness and Stereotypic thinking in social judgment. Journal of Personality and Social Psychology. 66(4): 621-632.