olfaktori

Olfaktori is a term used in some languages to refer to the olfactory system or sense of smell. It encompasses the peripheral sensory apparatus, the neural pathways that convey odor information, and the brain regions that process and interpret this information.

Anatomy and perception

In humans the primary olfactory structures are located in the nasal cavity and the brain. The olfactory epithelium lines the superior part of the nasal cavity and contains olfactory receptor neurons, supporting cells, and basal stem cells. Odorant molecules dissolve in mucus and bind to specific odorant receptors on the cilia of olfactory neurons. Each neuron expresses a single receptor type, and neurons expressing the same receptor converge their axons onto dedicated glomeruli in the olfactory bulb, creating a spatial map of odor information.

Mechanism and pathways

Odorant binding activates G-protein coupled signaling, increasing cAMP and opening ion channels to generate electrical signals. The olfactory bulb relays input to higher brain regions, including the piriform cortex, entorhinal cortex, and amygdala, with additional projections to the orbitofrontal cortex. The combined activity across receptor types supports the perception and discrimination of a vast array of odors, including perceptual qualities such as intensity and pleasantness, and it links odor with memory and emotion through limbic connections.

Regeneration, variation, and clinical relevance

Olfactory receptor neurons continually regenerate from basal cells, enabling long-term sensory maintenance but making the system vulnerable to environmental damage and age-related decline. Humans possess hundreds of olfactory receptor genes, with substantial interspecies variation. Clinically, olfaktori function can be impaired by infections, trauma, nasal obstruction, or neurodegenerative conditions, leading to anosmia or hyposmia. Olfactory testing and chemosensory training are common approaches in assessment and rehabilitation.

See also: olfaction, olfactory receptor, olfactory bulb, gustation.