Latest paper published: Nicotine dependence increases the number of immature neurons in the hippocampus.
It was believed that nicotine and tobacco smoke decrease the production of new neurons in adult. However, previous studies have used animal models with limited relevance to nicotine dependence such as limited access to nicotine self-administration or passive exposure to nicotine of tobacco smoke.
New results from the George and Mandyam labs (link to PDF), using a novel animal model of escalation of nicotine intake, demonstrate that nicotine dependence instead increases the number of immature neuron in the hippocampus. Moreover, the amount of nicotine self-administered highly predicted the number of immature neurons.
These new findings completely change our understanding of the effects of nicotine on neurogenesis. The next big challenge will be to determine the functional consequences of such an increase in immature neurons and if it causes cognitive and emotional deficits in dependent subjects.
Cohen A, Soleiman MT, Talia R, Koob GF, George O, Mandyam CD. Extended access nicotine self-administration with periodic deprivation increases immature neurons in the hippocampus. Psychopharmacology (Berl). 2014 Jul 26. [Epub ahead of print] PubMed PMID: 25059540.