piriform cortex (PIR)

The term piriform cortex (PIR) refers to a histologically defined struture on the mesioventral aspect of the limbic lobe in the human ( Yilmazir-Kanke-2012 ), macaque ( Paxinos-2009a ), rat ( Swanson-2004 ) and mouse ( AMBA-2024 ). In the human and mouse it is one of three parts of the anterior parahippocampal gyrus (PHGa). The others are the periamygdalar cortex (PAC) and the entorhinal cortex (ENT). In the human the PIR has two parts observable by dissection: piriform cortex of the frontal lobe (PIRflb) and piriform cortex of the limbic lobe (PIRllb) ( Mai-1997 ). In other species its boundaries are defined by multiple criteria. Primary excitatory inputs to the PIR are from the mitral cell ensemble of the main olfactory bulb (MCEm) and the tufted cell ensemble of the main olfactory bulb (TCE). Functionally, the PIR is the largest area of cerebral cortex (CTX) in the olfactory system (OSY). ( NeuroNames ).

Also known as: prepiriform cortex, gyrus olfactorius lateralis, piriform olfactory cortex, prepyriform area, Cortex piriformis, Regio praepiriformis, lateral olfactory gyrus, prepyriform cortex, piriform cortex (Price), Palaeocortex II, Eupalaeocortex, piriform cortex, Area prepiriformis, piriform area, pyriform area, (pre-)piriform cortex

NeuroNames ID: 165

All Names & Sources

Showing 30 synonym(s)

Language
Name
Source
English
(pre-)piriform cortex
English
lateral olfactory gyrus
English
piriform area
English
piriform cortex
English
piriform cortex (Price)
English
piriform olfactory cortex
English
prepiriform cortex
English
prepiriform cortex
English
prepyriform area
English
prepyriform area
English
prepyriform cortex
English
pyriform area
No specie structures found

No specie structures available for this concept.

Models Where It Appears
Structural CNS Model - Macaque

Brain structures of the macaque are illustrated in BrainInfo’s NeuroMaps macaque brain atlas. Structures are grouped by proximity in a hierarchy corresponding to the central nervous system hierarchy of NeuroNames ( Bowden-1995 Martin-2000 ). Structures in the NeuroMaps atlas are based on the segmentation of an MRI of the brain of a 3-year old male rhesus macaque (Macaca mulatta). The atlas is most useful for targeting structures for implantating electrodes and chemtrodes. Updated 29 Oct 2025.

Functional CNS Model - Rat

The Functional CNS Model - Rat (FMrat) ( Swanson-2004) is one of three hierarchical models representing the internal organization of the central nervous system (CNS). The others are the Structural CNS Model - Human (SThmn) and the Functional CNS Model - Human (FMhmn). The FMrat model represents the basic organization of the mouse ( Hof-2000 AMBA-2024 ) and, presumably, other rodents. Functional CNS models differ from structural models in that structures are defined and named by connectivity rather than by proximity to other structures at the same level. Functional models are more useful for representing longitudinal components of are grouped based on information drawn from multiple neuroscientific disciplines. such as connections, neurochemical characteristics, and role in physiogical and behavioral processes. While the Functional Model was developed primarily for an atlas of the rat brain ( Swanson-2004 ), the hierarchical organization of structures is for the most part applicable to the human, macaque, mouse and other mammalian brains as well. Structures at lower levels of the Functional CNS hierarchy are largely the same as in the Classical and Developmental Models, i.e., they were originally identified by stains for gray matter (Nissl substance) and white matter (myelin). At the next higher level they are grouped into basic connectional and functional systems of the CNS, such as the subcortical sensory systems, the brainstem motor system and the behavioral state system. At the highest levels CNS structures are grouped on the basis of dissection and embryologic precursors into cerebrum ( cerebral cortex and cerebral nuclei ), cerebellum, and cerebrospinal trunk.