Integrating new neurons into the adult olfactory bulb: joining the network, life-death decisions, and the effects of sensory experience.
In contrast to the situation in the developing brain, neurons born during adulthood must integrate into established neuronal networks characterized by ongoing activity. For sensory systems, this neuronal activity is driven mainly by external stimuli that can lead to experience-dependent morpho-functional changes in adult circuits. Here, we describe new insights into the mechanisms by which sensory experience might govern the targeting of adult-generated neurons to appropriate regions, their differentiation into distinct neuronal subtypes, and finally their survival in the adult olfactory bulb. We propose not only that neurogenesis depends on the degree of sensory experience, but also that new neurons bring unique features to the operational network, allowing a continuous adjustment of information processing in response to an ever-changing external word.
Lledo
Pierre-Marie
PM
Laboratory of Perception and Memory, Centre National de la Recherche Scientifique, Unité de Recherche Associée 2182, Pasteur Institute, 25 rue du Docteur Roux, 75724 Paris Cedex 15, France. pmlledo@pasteur.fr
Saghatelyan
Armen
A
D000818:Animals; D016923:Cell Death / Q000502:physiology; D006801:Humans; D009415:Nerve Net / Q000166:cytology* / Q000502:physiology; D009474:Neurons / Q000166:cytology* / Q000502:physiology; D009475:Neurons, Afferent / Q000166:cytology* / Q000502:physiology; D009830:Olfactory Bulb / Q000166:cytology* / Q000502:physiology