Linking adult olfactory neurogenesis to social behavior

Abstract

In the adult brain, new neurons are added to two brain areas: the olfactory bulb (OB) and the hippocampus. Newly-generated neurons integrate into the preexisting circuits, bringing a set of unique properties, such as increased plasticity and responsiveness t stimuli. However, the functional implications of the constant addition of these neuron remain unclear, although they are believed to be important for learning and memory. Th levels of neurogenesis are regulated by a variety of environmental factors, as well a during learning, suggesting that new neurons could be important for coping with changin environmental demands. Notably, neurogenesis has been shown to be physiologicall regulated in relation to reproductive behavior: neurogenesis increases in female mic upon exposure to cues of the mating partners, during pregnancy and lactation, and i male mice upon exposure to their offspring. In this scenario, and because of the ke contribution of olfaction to maternal behavior, we sought to investigate the contributio of adult-generated neurons in the olfactory system to maternal behavior and offsprin recognition. To do so, we selectively disrupted neurogenesis in the olfactory pathwa of female mice using focal irradiation. Disruption of adult neurogenesis in the OB di not affect maternal behavior, or the ability of female mice to discriminate familiar from unfamiliar pups. However, reduction of olfactory neurogenesis resulted in abnormal social interaction of female mice, specifically with male conspecifics. Because the olfactor system is crucial for sex recognition, we suggest that the abnormal interaction with male could result from the inability to detect or discriminate male-specific odors and coul therefore have implications for the recognition of potential mating partners. Here, I review the results of our study and others, and discuss their implications for our understandin of the function of adult neurogenesis. © 2012 Feierstein.