The Olfactory Bulb is important for the sense of smell.

The olfactory bulb, the center of smell detection, houses numerous primitive stem cells that normally feed the constant, life-long regeneration of odor-detecting nerves. Because they are found in a fairly accessible region of the brain and could conceivably be removed from a person's olfactory bulb without causing permanent damage, adult olfactory bulb stem cells are a potential non-embryonic source for cells that could prove useful in replacing nerve cells lost due to injury or diseases like ALS and Parkinson's.

The Olfactory Bulb contains the neuronal somas and dendrites that receive the synaptic input from the neurons comprising cranial nerve ( I ), the olfactory nerve.