The common properties of neurogenesis in the adult brain: from invertebrates to vertebrates

A Hypothesis About the Role of Adult Neurogenesis in Hippocampal Function

“…Adult neurogenesis has been highly conserved throughout evolution; it has been observed in the central nervous systems of invertebrates and vertebrates such as fish, birds, and mammals (1,5,10,26). Most studies carried out under physiological conditions in adult mammals indicate that significant levels of neurogenesis occur exclusively in the dentate gyrus of the hippocampus (DG; FIGURE 1) and the olfactory bulb (OB).…”

Neurogenic and Neuroendocrine Effects of Goldfish Pheromones

“…Adult neurogenesis is more widespread and affects more brain regions in nonmammals than in mammals. The restriction of adult neurogenesis to telencephalic areas seems to be a common feature of all amniotic vertebrates (Cayre et al, 2002). In contrast, adult neurogenesis is observed in the olfactory bulb, dorsal telencephalon, optic tectum, cerebellum, and the brainstem in fish (Zupanc, 2006).…”

“…Several environmental factors, such as seasonal variations in temperature and photoperiod, and sensory inputs influence adult neurogenesis (Cayre et al, 2002). Enriched sensorial and social environments enhanced neurogenesis in cricket mushroom bodies (Scotto Lomassese et al, 2000), crayfish brain (Sandeman and Sandeman, 2000), and the hippocampus of birds and rodents (Kempermann et al, 1997(Kempermann et al, , 1998Patel et al, 1997;Gould et al, 1999;van Praag et al, 1999a,b;Ambrogini et al, 2000).…”

“…In decapod crustaceans, persistent neurogenesis among olfactory projection neurons is a common principle that shapes the adult brain, indicating a remarkable degree of lifelong structural plasticity (Harzsch et al, 1999). In some insects, persistent neurogenesis occurs in the mushroom bodies, which are brain structures involved in learning and memory and considered as functional analogues of the hippocampus (Cayre et al, 2002). However, this phenomenon is absent in other insects and therefore cannot be seen as a common feature in all insect brains (Fahrbach et al, 1995;Gronenberg et al, 1996).…”

“…Adult neurogenesis in both vertebrates and invertebrates appears to be regulated by internal factors such as hormones, neurotransmitters, and growth factors, and by external factors such as environmental cues (Scotto Lomassese et al, 2000;Cayre et al, 2002). Pheromones are a class of environmental cues that are known to exert profound effects in insect brains (Grozinger et al, 2003Alaux and Robinson, 2007;Beggs et al, 2007;Grozinger and Robinson, 2007;Vergoz et al, 2007).…”