Where it is
At the front end of the brain, below the frontal lobes, on the cribriform plate.
- Layer
- Organs
- System
- Nervous system
- Region
- Head
What it is and what it does
The olfactory bulb is the ventral structure of the hemisphere, part of the rhinencephalon, resting on the cribriform plate of the ethmoid, through which the olfactory nerves enter; the olfactory peduncle attaches it to the brain. Here the axons of the neurons from the nose synapse in glomeruli with the mitral cells, whose axons leave through the olfactory tract. In the dog it takes up about 0.31 % of brain volume, measured on five fixed brains (Kavoi and Hassanali 2011).
Worth remembering
Its share of the brain has been measured (0.31 % in the dog); “X times bigger than in humans” is not a measurement.
Names
- Latin term: bulbus olfactorius.
- In Romanian: Bulbul olfactiv (Romanian page).
In the atlas lessons
Journey of a scent (5 min):
From the bulb, the signal goes to the piriform lobe, then to the amygdala, the hippocampus and the frontal cortex: steps 13–19 of the “Journey” and the “Dog brain” page.
The head: what you see, what is underneath (6 min).
The brain and scent: where the trail ends up (7 min):
The olfactory bulb sits on the cribriform plate, under the frontal lobes: the first station of a scent. In the dog, 0.31 % of brain volume, measured on five brains (Kavoi 2011).