accessory olfactory bulb
Acronym: OLBa
The term accessory olfactory bulb refers to one of two types of olfactory bulbs. A histologically defined structure of the olfactory system, it receives input from the vomeronasal organ via the vomeronasa-terminall nerve complex. Unlike the main olfactory bulb, which provides input to several parts of the olfactory system the OLBa projects only to the cortical amygdalar nucleus ( Buck-2013 ). It is most prominent in the rat ( Swanson-2004 ) and the mouse ( Dong-2004 ).
      It is a vestigial structure in the human ( Witt-2002 ) and, if it exists at all ( Francia-2014 ), in the macaque ( Zhang-2003 ). Evolutionary biologists attribute its vestigial status in primates to their greater use of the visual and auditory systems in adaptation to the environment ( Witt-2002 ).
      It differs functionally from the main olfactory bulb in that it is part of the neural circuitry tor responding to pheromones, the airborne chemicals from an individual that trigger appropriate reproductive behavior and physiological changes in another of the same species ( Zhang-2003 ).
      Functionally, the vomeronasal organ and associated structures are believed by some authors to perform a role in controlling human reproductive functions and behaviors. As a source of input to the olfactory system separate from the main olfactory epithelium they may play a role in the unconscious perception of special odorants that influence behavior in the form of mate selection and neuromodulation of reproductive hormonal systems via the hypothalamic-pituitary-gonadal axis ( Sonne-2023 ). Updated 13 Jun 2024.

Also known as: No other name for this structure has appeared in PubMed.NeuroNames ID : 1565

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