Adult neurogenesis in the hippocampal dentate gyrus affects sparsely synchronized rhythms, associated with pattern separation and integration

We are concerned about sparsely synchronized rhythms (SSRs), associated with diverse cognitive functions, in the hippocampal dentate gyrus. Distinctly, adult-born immature GCs (imGCs) emerge through neurogenesis, in addition to the mature granule cells (mGCs) (emerged in the developmental stage). In prior work, these mGCs and imGCs were found to exhibit their distinct roles in pattern separation and integration for encoding cortical inputs, respectively. But, the underlying dynamical mechanismremains unclear. In this paper, we first study influence of the young adult-born imGCs on emergence of SSRs in the populations of the mGCs and the imGCs; population and individual firing behaviors in the SSRs are intensively studied. We then examine how the SSRs play a role in the underlying mechanism for pattern separation and integration. Particularly, quantitative relationship between SSRs of the mGCs and the imGCs and their pattern separation and integration is investigated.