Human Pheromones: 2010 Powerpoint slides and 2011 poster presentation
February 10, 2012 | James Kohl
Here are the slides with text from a 20 minute-long presentation: Human pheromones: linking neuroendocrinology and ethology (revisited)
Background / Purpose: 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.
Main conclusion: 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.
Next steps: 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.
An updated poster presentation of the one presented in 2010 is also available: Human pheromones, epigenetics, physiology, and the development of animal behavior.
Background/Purpose: We evaluated individual video-taped fifteen-minute interactions of fourteen women with fertile phase levels of Luteinizing Hormone (LH) during a cooperative task. During the task, our male accomplice wore either a standardized androstenol / androsterone mixture diluted in propylene glycol, or just the diluents; with sandalwood odor added to keep him blind to his condition.
Main conclusion: When he was wearing the mixture compared to when he wore the diluent, women were more likely to make eye contact (t (12) = 3.43, p = 0.01; IRR: r = 0.964, p = 0.01). They also laughed more (t (12) = 5.20, p < 0.01; IRR: r = 0.810, p = 0.01), and they subsequently rated themselves as being more attracted to him (t (12) = 2.786, p = 0.016).
Our results combine the known effects of androstenol on LH and on mood with a likely behavioral affect of androsterone.