Smelling of odorous sex hormone-like compounds causes sex-differentiated hypothalamic activations in humans

Neuron. 2001 Aug 30;31(4):661-8. doi: 10.1016/s0896-6273(01)00390-7.


The anatomical pathways for processing of odorous stimuli include the olfactory nerve projection to the olfactory bulb, the trigeminal nerve projection to somatosensory and insular cortex, and the projection from the accessory olfactory bulb to the hypothalamus. In the majority of tetrapods, the sex-specific effects of pheromones on reproductive behavior is mediated via the hypothalamic projection. However, the existence of this projection in humans has been regarded as improbable because humans lack a discernable accessory olfactory bulb. Here, we show that women smelling an androgen-like compound activate the hypothalamus, with the center of gravity in the preoptic and ventromedial nuclei. Men, in contrast, activate the hypothalamus (center of gravity in paraventricular and dorsomedial nuclei) when smelling an estrogen-like substance. This sex-dissociated hypothalamic activation suggests a potential physiological substrate for a sex-differentiated behavioral response in humans.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Dorsomedial Hypothalamic Nucleus / cytology
  • Dorsomedial Hypothalamic Nucleus / physiology
  • Female
  • Gonadal Steroid Hormones / physiology*
  • Humans
  • Hypothalamus / cytology
  • Hypothalamus / physiology*
  • Male
  • Odorants
  • Olfactory Bulb / cytology
  • Olfactory Bulb / physiology*
  • Olfactory Pathways / cytology
  • Olfactory Pathways / physiology
  • Preoptic Area / cytology
  • Preoptic Area / physiology
  • Sex Characteristics*
  • Smell / physiology*
  • Somatosensory Cortex / cytology
  • Somatosensory Cortex / physiology
  • Tomography, Emission-Computed
  • Trigeminal Nerve / cytology
  • Trigeminal Nerve / physiology
  • Ventromedial Hypothalamic Nucleus / cytology
  • Ventromedial Hypothalamic Nucleus / physiology


  • Gonadal Steroid Hormones