Physio 09: Smell & Taste

Smell and taste are often treated as minor senses, yet they are among the most ancient, direct, and emotionally powerful sensory systems in human physiology. Unlike vision or hearing, they rely on chemical recognition—molecules binding to receptors—and they connect to the brain with remarkably little filtration.In this episode, Medlock Holmes explores how olfaction and gustation translate chemical signatures into perception. We examine receptor diversity, signal transduction pathways, and the neural organisation that allows thousands of odours and flavours to be distinguished from subtle molecular differences.This episode also explores why smell is uniquely tied to memory and emotion, and why taste functions less as a pleasure system and more as a biological safety mechanism. Together, these senses remind us that physiology evolved not to describe the world—but to keep us alive within it.Here, perception is not distant or abstract.It is ingested, inhaled, and remembered.Key Takeaways* Smell and taste are chemical senses based on receptor–ligand interactions* Olfactory receptors show vast diversity and combinatorial coding* Taste prioritises safety, nutrient detection, and aversion* Olfactory pathways have direct links to emotional and memory centres* Perception reflects biological relevance more than sensory precision This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit drmanaankarray.substack.com/subscribe