Odorant category profile selectivity of olfactory cortex neurons
1Department of Physiology, Graduate School of Medicine, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan.
Summary
Individual rat olfactory cortex neurons integrate signals from distinct food odorant categories. This neural integration enhances the ability to distinguish between different food smells by processing complex odor profiles.
Area of Science:
- Neuroscience
- Olfactory System Research
- Sensory Perception
Background:
- The olfactory cortex receives input from the olfactory bulb, with individual neurons integrating signals from various odorants.
- A key question is identifying the specific types of odorants integrated by single cortical neurons.
- Natural foods emit fixed combinations of odorants, forming characteristic olfactory profiles.
Purpose of the Study:
- To investigate if olfactory cortical neurons integrate signals from distinct component odorants of natural foods.
- To determine if neurons respond selectively to single or combined categories of food odorants.
Main Methods:
- Recording single-unit spike responses of neurons in the rat anterior piriform cortex.
- Stimulating neurons with a panel of eight food-related categories of odorants and their mixtures.
Main Results:
- Many cortical neurons exhibited selective tuning to single or specific combinations of odorant categories.
- Observed mixture facilitation and inhibition in response to odorant mixtures.
- Evidence suggests olfactory circuits enhance category-profile selectivity in individual neurons.
Conclusions:
- Distinct categories of food-born odorant signals are integrated within individual olfactory cortical neurons.
- These neurons likely detect the odorant-category profile of foods.
- This mechanism aids in distinguishing between different food odors.
Related Concept Videos
01:25Olfaction
The sense of smell is achieved through the activities of the olfactory system. It starts when an airborne odorant enters the nasal cavity and reaches olfactory epithelium (OE). The OE is protected by a thin layer of mucus, which also serves the purpose of dissolving more complex compounds into simpler chemical odorants. The size of the OE and the density of sensory neurons varies among species; in humans, the OE is only about 9-10 cm2.
The olfactory receptors are embedded in the cilia of the...
The olfactory receptors are embedded in the cilia of the...
01:20Physiology of Smell and Olfactory Pathway
Humans detect odors with the help of specialized cells located in the upper part of the nasal cavity, called olfactory receptor neurons (ORNs). ORNs possess hair-like structures called cilia, which are receptive to sensations from the inhaled air. When an odorant molecule binds to a specific receptor on the cell of the cilia, it leads to a series of events that ultimately cause the ORN to send electrical signals to the olfactory bulb in the brain through the olfactory nerves.
The olfactory...
The olfactory...
01:03Olfactory Receptors: Location and Structure
The process of olfaction, also known as the sense of smell, is a sophisticated chemical response system. The specialized sensory neurons that facilitate this process, known as olfactory receptor neurons, are situated in an upper segment of the nasal cavity, known as the olfactory epithelium. Olfactory sensory neurons are bipolar, with their dendrites extending from the epithelium's apex into the mucus that lines the nasal cavity. Airborne molecules, when inhaled, traverse the olfactory...
01:25Dose-Response Relationship: Selectivity and Specificity
Drugs exert their therapeutic effects by interacting with receptors, enzymes, or ion channels that are present throughout the human body. The strength and duration of the interaction between a drug and its target receptor are characterized by the selectivity and specificity of the drug. Selectivity refers to a drug's strong preference for its intended target over other targets. For instance, isoprenaline, a non-selective β-adrenergic agonist, interacts with both β1- and β2-adrenergic receptors...