 | This articleneeds additional citations forverification. Please helpimprove this article byadding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Olfactory tract" – news ·newspapers ·books ·scholar ·JSTOR(December 2008) (Learn how and when to remove this message) |
| Olfactory tract | |
|---|---|
 Olfactory peduncle lying in olfactory sulcus and olfactory striae labelled (anterior at top) | |
| Details | |
| System | Olfactory system |
| Location | Brain |
| Identifiers | |
| Latin | tractus olfactorius |
| NeuroNames | 283 |
| NeuroLex ID | birnlex_1663 |
| TA98 | A14.1.09.431 |
| TA2 | 5539 |
| FMA | 77626 |
| Anatomical terms of neuroanatomy | |
Theolfactory tract (olfactory peduncle orolfactory stalk) is abilateral bundle ofafferent nerve fibers from themitral andtufted cells of theolfactory bulb that connects to several target regions in the brain, including thepiriform cortex,amygdala, andentorhinal cortex. It is a narrowwhite band, triangular oncoronal section, the apex being directed upward.
The term olfactory tract is a misnomer, as the olfactory peduncle is actually made up of the juxtaposition of two tracts, the medial olfactory tract (giving the medial and intermediate olfactory stria) and the lateral olfactory tract (giving the lateral and intermediate olfactory stria).[1] However, the existence of the medial olfactory tract (and consequently the medial stria) is controversial in primates (including humans).[2]
The olfactory peduncle andolfactory bulb lie in theolfactory sulcus[3] asulcus formed by themedial orbital gyrus on the inferior surface of eachfrontal lobe. The olfactory peduncles lie in the sulci which run closely parallel to the midline. Fibers of the olfactory peduncle appear to end in the antero-lateral part of theolfactory tubercle, the dorsal and external parts of theanterior olfactory nucleus, the frontal and temporal parts of theprepyriform area, the cortico-medial group ofamygdala nuclei and thenucleus of the stria terminalis.[4]
The olfactory peduncle divides posteriorly into three main branches: the medial, intermediate and lateral striae. The olfactory peduncle thus terminates in a triangular structure called theolfactory trigone. Caudal to these elements is theanterior perforated substance, the anterior part of which is marked by the relief of theolfactory tubercle. Finally, projections from the olfactory peduncle to the anterior olfactory nucleus are sometimes grouped together under the name ofsuperior olfactory stria.[1]
The terms olfactory tubercle and olfactory trigone are commonly confused in the literature.
Themedial olfactory striais classically described as running medially behind theparolfactory area (hence its name) and terminating in thesubcallosal gyrus.
However, this description has been rejected for some fifty years.[2] The medial olfactory stria is now described as terminating much more medially, in the ventraltenia tecta.[1]
Theintermediate olfactory striais the branch (or branches) extending from the medial or lateral olfactory striae to the olfactory tubercle and anterior perforated substance. Trolard's term "pectineal formation " is used to refer to multiple intermediate striae extending from the lateral olfactory stria.[1]
Thelateral olfactory stria is directed across the lateral part of the anterior perforated substance and then bends abruptly medially toward theuncus of theparahippocampal gyrus.
Destruction to the olfactory peduncle results in ipsilateralanosmia (loss of the ability to smell). Anosmia either total orpartial is a symptom ofKallmann syndrome agenetic disorder that results in disruption of the development of the olfactory peduncle.[5][6] The depth of the olfactory sulcus is an indicator of suchcongenital anosmia.[7]
{{cite book}}: CS1 maint: location missing publisher (link)
This article incorporates text in thepublic domain frompage 826 of the 20th edition ofGray's Anatomy(1918)
