olfactory tubercle (OTB)

The term olfactory tubercle refers to a histologically defined, predominantly cellular structure. It is located on the ventral surface of the basal forebrain, caudal to the anterior olfactory nucleus, medial to the olfactory tract, rostral to the piriform cortex and ventral to the nucleus accumbens and substantia innominata. It contains some islands of Calleja. In the rat ( Swanson-2004 ) and the mouse ( Hof-2000 ) it protrudes on the rostroventral surface of the basal forebrain and is clearly stratified. In primates, however, it does not protrude from surrounding areas and is penetrated by numerous small blood vessels. These give it an appearance on dissection that accounts for the name 'anterior perforated substance' in human neuroanatomy ( Crosby-1962 ). In the macaque it is somewhat more prominent than in the human and bounded medially by the tenia tecta ( Price-2004 ). Functionally it is part of the olfactory system, which mediates the sense of smell ( Buck-2013 ). A connection to the periaqueductal gray suggests a behavioral role in eating (Zhou-2024). Inasmuch as OTB is part of the ventral striatum ( Heimer-1995 ), shares a pattern of connectivity with neighboring nucleus accumbens (ACB), is densely innervated by dopaminergic fibers and supports electrical self-stimulation, it is believed to be involved in motivation and reward-supported learning ( Wesson-2020 ). The observation that its olfactory input is solely from the main olfactory bulb (OLBm) ( Buck-2013 ) would suggest that its primary behavioral functions might be approach and avoidance responses to positive and negative oderants from potentially edible substances. Updated 20 Jun 2024.

Also known as: olfactory tubercle (Ganser), tuber olfactorium, olfactory area (Carpenter), anterior perforated substance, Substantia perforata anterior, anterior perforated space, anterior perforated area, olfactory tubercle, Tuberculum olfactorium, Eminentia parolfactoria, Area olfactoria (Mai), olfactory area (Mai), rostral perforated substance, tubular striatum

NeuroNames ID: 282

All Names & Sources

Showing 36 synonym(s)

Language
Name
Source
English
anterior perforated area
English
anterior perforated space
English
anterior perforated substance
English
olfactory area (Carpenter)
English
olfactory area (Mai)
English
olfactory tubercle
English
olfactory tubercle
English
olfactory tubercle (Ganser)
English
rostral perforated substance
English
tubular striatum
Species With The Structure
Equivalent By Human Macaque Rat Mouse
Topology Has The Structure Has The Structure Has The Structure Has The Structure

Showing 17 record(s)

Basis
Has Equivalent
Organism
Their Name
Source
Topology
Yes
anterior perforated area
Topology
Yes
anterior perforated space
Topology
Yes
Area olfactoria (Mai)
Topology
Yes
Eminentia parolfactoria
Topology
Yes
olfactory area (Carpenter)
Topology
Yes
olfactory area (Mai)
Topology
Yes
olfactory tubercle
Topology
Yes
rostral perforated substance
Topology
Yes
Substantia perforata anterior
Topology
Yes
tuber olfactorium
Topology
Yes
Tuberculum olfactorium
Topology
Yes
anterior perforated substance
Topology
Yes
Area olfactoria (Mai)
Topology
Yes
Substantia perforata anterior
Topology
Yes
olfactory tubercle
Topology
Yes
olfactory tubercle (Ganser)
Topology
Yes
olfactory tubercle
Hof-2000
Page 260
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.