Adult-born neurons facilitate olfactory bulb pattern separation during task engagement

2017 Fiscal Year Final Research Report

• Project/Area Number: 15H05570
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Neurophysiology / General neuroscience
• Research Institution: Kyoto University
• Principal Investigator: Imayoshi Itaru 京都大学, 生命科学研究科, 特定准教授 (60543296)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: ニューロン新生 / 神経幹細胞 / 嗅球

Outline of Final Research Achievements

The rodent olfactory bulb incorporates thousands of newly generated inhibitory neurons daily throughout adulthood. Here we adopted a genetic method to inducibly suppress adult neurogenesis and investigated its effect on behavior and bulbar activity. Mice without young adult-born neurons (ABNs) showed normal ability in discriminating very different odorants but were impaired in fine discrimination. Furthermore, two-photon calcium imaging of mitral cells (MCs) revealed that the ensemble odor representations of similar odorants were more ambiguous in the ablation animals. This increased ambiguity was primarily due to a decrease in MC suppressive responses. Intriguingly, these deficits in MC encoding were only observed during task engagement but not passive exposure. Our results indicate that young olfactory ABNs are essential for the enhancement of MC pattern separation in a task engagement-dependent manner, potentially functioning as a gateway for top-down modulation.

Free Research Field

神経科学