We examined the physiological and psychological effects of nanomolar amounts of steroids applied directly under the nose (Δ4, 16-androstadien-3-one and 1, 3, 5, (10), 16-estratetraen-3-ol). These potential human chemosignals were not consciously discernible in a strong-odor carrier (clove oil and propylene glycol). In a double-blind, within-subject, repeated-measures experiment with 65 subjects, we demonstrated that both steroids produced sustained changes in digit skin temperature and palmar skin conductance (an indicator of sympathetic nervous system tone) while the subjects were completing psychological questionnaires or reading. These effects, however, did not follow the sex-stereotyped pattern predicted by a sex attractant function. Both androstadienone and estratetraenol raised the skin temperature of men's hands and lowered it in women. Likewise, each steroid increased skin conductance, with a significantly greater effect on women than men. Women's responses were observed only in the sessions run by the male tester, an effect that may or may not be solely attributable to tester sex. Men's responses, in contrast, were not affected by this difference in socioexperimental condition. Similarly, women experienced an immediate increase in positive mood only in the presence of the male tester, while men's responses were unaffected by this socioexperimental context. One source of this sex difference may be the fact that the majority of women were in the late follicular phase of their menstrual cycle. Although it is premature to classify these steroids as pheromones, our data suggest that they function as chemosignals that modulate autonomic nervous system tone as well as psychological state.
|Original language||English (US)|
|Number of pages||13|
|Journal||Physiology and Behavior|
|State||Published - 2001|
Bibliographical noteFunding Information:
This work was supported by the Mind–Body Network of the John D. and Catherine T. MacArthur Foundation, the NIH MERIT award R37 MH41788 to Martha K. McClintock, as well as the NIH MD/PhD Training Grant HD-07009 and Olfactory Research Fund's Tova Fellowship to Suma Jacob. We also thank Sheila Garcia for her commitment and significant help with many aspects of data collection and processing. Bethanne Zelano's assistance with graphing is greatly appreciated. Thanks to Harriet de Wit for input on the psychopharmacological battery and Ron Thisted and John Cacioppo for statistical advice.
- Autonomic nervous system