Adult Neurogenesis in the Central Olfactory Pathway of Decapod Crustaceans

Abstract

Until about 10 years ago it was commonly believed that in the central nervous system of adult animals a de novo generation of neurons, i.e., neurogenesis, did not occur, except in some special cases. These well-accepted “exceptions” were birds, in which it had been demonstrated that seasonal changes in the size of brain nuclei responsible for song production involve periodic neurogenesis (e.g., Goldman and Nottebohm 1983; Paton and Nottebohm 1984), and goldfish, in which not only the body but also the brain grows continuously throughout adult life, the latter being at least partially due to neurogenesis (e.g., Raymond and Easter 1983). In the 1970s and 1980s, some evidence for adult neurogenesis was also collected for the brain of mammals (Kaplan and Hinds 1977; Bayer 1982; Kaplan et al. 1985; Crespo et al. 1986), but these scattered reports had not caused a revision of the general notion that neurogenesis was absent from the adult mammalian brain (e.g., Purves 1988).