Psychological effects of subthreshold exposure to the putative human pheromone 4,16-androstadien-3-one.

Research on human putative pheromones has recently focused on the effects of exposure to 4,16-androstadien-3-one (androstadienone). This steroid has been observed in the skin, axillary hair, and blood plasma, primarily in males. In addition to effects of the steroid on measures of physiological arousal and brain blood flow, positive mood effects have also been reported. The current study further investigated mood effects of androstadienone exposure (250 microM) in women in two experiments. Through psychophysical testing of each individual we controlled for whether any observed mood effects could be related to sensory detection of the steroid. In both experiments, we observed positive changes of women's feeling of being focused, which could not be related to sensory detection of the steroid. Overall, the patterns of results were significantly correlated between the two experiments. In conclusion, this study corroborates earlier findings suggesting that androstadienone exposure yields effects on women's mood; the feeling of being focused. The mood effects were not dependent on menstrual cycle phase. Further, these effects are replicable and occur also when androstadienone detection is rigorously controlled for across variation in menstrual cycle.