Olfactory tracts

Olfactory Tracts

The olfactory tracts are a pair of white bands, each about 3.5 cm long, that connect the olfactory bulbs to the olfactory cortex in the brain. They are part of the olfactory system, which is responsible for the sense of smell.

Anatomy

The olfactory tracts begin at the posterior end of the olfactory bulbs. From there, they extend posteriorly over the cribriform plate of the ethmoid bone, along the lateral part of the olfactory groove, and into the anterior cranial fossa. They then curve medially and posteriorly around the anterior perforated substance, ending in the olfactory cortex.

The olfactory tracts are divided into two distinct parts: the lateral and medial striae. The lateral stria carries fibers to the primary olfactory cortex, which includes the piriform cortex, the anterior olfactory nucleus, the periamygdaloid cortex, and the rostral part of the entorhinal cortex. The medial stria carries fibers to the opposite olfactory bulb, crossing over in the anterior commissure.

Function

The olfactory tracts transmit olfactory information from the olfactory bulbs to the olfactory cortex, where it is processed and interpreted as different smells. This information is then sent to other areas of the brain, including the limbic system and the orbitofrontal cortex, for further processing and integration with other sensory information.

Clinical significance

Damage to the olfactory tracts can result in anosmia, a loss of the sense of smell. This can be caused by a variety of conditions, including head trauma, neurodegenerative diseases such as Parkinson's disease and Alzheimer's disease, and tumors in the brain. Anosmia can also be a symptom of COVID-19.