Human pheromones: linking neuroendocrinology and ethology (revisited)

Their conversion from chemical signals to the mammalian brain’s common language of electrical signals allows food odors and pheromones to activate genes. In this mammalian model, electrostatic gene activation by pheromones links them to a marker of neuronal activity, gene expression, and changes in hypothalamic gonadotropin releasing hormone (GnRH) secretion.

Changes in GnRH secretion are evidenced in downstream effects on other hormone secretion throughout the hypothalamic-pituitary-gonadal (HPG) axis and hypothalamic-pituitary-adrenal (HPA) axis. Food odors and pheromones activate the prenatal organization of the HPG and HPA axes and postnatally “calibrate” the genetically predisposed survival potential of individuals and species. Calibration of odor preferences occurs via effects on synaptogenesis, synaptolysis, and apoptosis throughout life. In mammals, these effects of odors are routinely associated with neurotransmission, hippocampal neurogenesis, learning, and memory during classically conditioned hormone-driven changes in behavior. In people, these neurophysiological effects of calibration by odors are typically consciously associated only with input from spectral senses (e.g., vision and hearing), or tactile sensations.

Extension of this mammalian model to people explains how cerebral activation of hormone-secreting neurons and processes commonly attributed to individual components of the model, like genes or hormones, result in genetically predisposed phenotypic expression, which may or may not be physically or behaviorally manifested during development. The explanation includes (1) a cognitive component associated with the identification and categorization of some odors; (2) an emotional component associated with odors and increased or decreased arousal, appetite, and satiation; (3) a motivational component linked to processes that direct behavior toward or away from food odors and pheromones; and (4) a neurophysiological component, directly linked from odors to gene activation in hormone-secreting nerve cells of brain tissue; to HPG / HPA axis variability, and to behavior.

Author formulates and markets human pheromone-enhanced fragrance products, and disseminates information about pheromones via the domain Pheromones.com and other domains associated with the science of human pheromones.