| Piriform cortex | |
|---|---|
 Human brainstem anterior (piriform cortex not labeled, but most of it is visible near #7) | |
| Details | |
| Identifiers | |
| Latin | cortex piriformis |
| MeSH | D066195 |
| NeuroNames | 165 |
| NeuroLex ID | birnlex_1097 |
| FMA | 62484 |
| Anatomical terms of neuroanatomy | |
Thepiriform cortex, orpyriform cortex, is a region in thebrain, part of therhinencephalon situated in thecerebrum. The function of the piriform cortex relates tothe sense of smell.
The piriform cortex is part of therhinencephalon situated in thecerebrum.
In human anatomy, the piriform cortex has been described as consisting of the corticalamygdala,uncus, and anteriorparahippocampal gyrus.[1] More specifically, the human piriform cortex is located between theinsula and thetemporal lobe, anteriorly and laterally of the amygdala.[2][3]
The function of the piriform cortex relates toolfaction, which is the perception ofsmell. This has been particularly shown in humans for the posterior piriform cortex.[2]
The piriform cortex in rodents and some primates has been shown to harbor cells expressing markers of plasticity such asdoublecortin and PSA-NCAM which are modulated by the noradrenergic neurotransmitter system.[4][5]
The piriform cortex contains a critical, functionally definedepileptogenic trigger zone, "Area Tempestas".[6] From this site in piriform cortex chemical and electrically evoked seizures can be triggered. It is the site of action for the proconvulsant action of chemoconvulsants.[7]
Sometimes called theolfactory cortex,olfactory lobe orpaleopallium, piriform cortical regions are present in the brains ofamphibians,reptiles andmammals.
The piriform cortex is among three areas that emerge in thetelencephalon of amphibians, situatedcaudally to a dorsal area, which is caudal to a hippocampal area. Further along thephylogenic timeline, the telencephalic bulb of reptiles as viewed in a cross section of the transverse plane extends with thearchipallial hippocampus folding toward the midline and down as the dorsal area begins to form a recognizable cortex.
As mammalian brains developed, volume of the dorsal cortex increased in slightly greater proportion, as compared proportionally with increased overall brain volume, until it enveloped thehippocampal regions. Recognized asneopallium orneocortex, enlarged dorsal areas envelop thepaleopallial piriform cortex inhumans andOld World monkeys.
Amongtaxonomic groupings of mammals, the piriform cortex and theolfactory bulb become proportionally smaller in the brains ofphylogenically younger species. The piriform cortex occupies a greater proportion of the overall brain and of the telencephalic brains ofinsectivores than inprimates. The piriform cortex continues to occupy a consistent albeit small and declining proportion of the increasingly largetelencephalon in the most recent primate species while the volume of the olfactory bulb becomes less in proportion.