Dr. Noam Sobel: How Smells Influence Our Hormones, Health & Behavior | Huberman Lab Podcast

Olfactory System

The olfactory system is a complex network that plays a crucial role in sensory processing. Noam Sobel explains that the olfactory receptors in humans, numbering around 350, converge to specific locations in the olfactory bulb, forming a map that reflects receptor identity 1. This convergence allows for the identification of specific odors, such as coffee, by activating distinct receptor subtypes. Sobel highlights the widespread propagation of olfactory information throughout the brain, reaching areas like the amygdala and hypothalamus, which influences emotions and behavior 1.

Odorants interact with these receptors here in our epithelium, where they undergo what is referred to as transduction.

--- Noam Sobel

The olfactory system's sensitivity is underscored by its vulnerability to trauma, often resulting in loss of smell due to the delicate structure of the olfactory nerve 2.

   

Regeneration

Olfactory neurons possess unique regenerative properties, setting them apart from most central nervous system neurons. Andrew Huberman notes that these neurons can regenerate, although complete severance of the olfactory nerve often leads to permanent loss of smell 3. Recovery is possible if some nerve connections remain intact, with regeneration occurring along existing pathways. Sobel discusses congenital anosmia, a condition where individuals are born without a sense of smell, often diagnosed around age 14 4.

Most people who are one half of 1% of the human population, presumably is without the sense of smell and doesn't realize that until they're 14 years old.

--- Andrew Huberman

This condition impacts social interactions and lifespan, highlighting the importance of olfaction in human life 4.