Effects of adult-generated granule cells on coordinated network activity in the dentate gyrus

By Clay Lacefield, Vladimir Itskov, T. Reardon, R. Hen, Joshua A. Gordon. 2010

182 citations recorded by the source corpus.

Throughout the adult life of most mammals, new neurons are continuously generated in the dentate gyrus of the hippocampal formation. Recent work has documented specific cognitive deficits after elimination of adult hippocampal neurogenesis in rodents, suggesting that these neurons may contribute to information processing in hippocampal circuits. Young adult‐born neurons exhibit enhanced excitability and have altered capacity for synaptic plasticity in hippocampal slice preparations in vitro. Still, little is known about the effect of adult‐born granule cells on hippocampal activity in vivo. To assess the impact of these new neurons on neural circuits in the dentate, we recorded perforant‐path evoked responses and spontaneous network activity from the dentate gyrus of urethane‐anesthetized mice whose hippocampus had been focally X‐irradiated to eliminate the population of young adult‐born granule cells. After X‐irradiation, perforant‐path responses were reduced in magnitude. In contrast, there was a marked increase in the amplitude of spontaneous γ‐frequency bursts in the dentate gyrus and hilus, as well as increased synchronization of dentate neuron firing to these bursts. A similar increase in gamma burst amplitude was also found in animals in which adult neurogenesis was eliminated using the GFAP:TK pharmacogenetic ablation technique. These data suggest that young neurons may inhibit or destabilize recurrent network activity in the dentate and hilus. This unexpected result yields a new perspective on how a modest number of young adult‐generated granule cells may modulate activity in the larger population of mature granule cells, rather than acting solely as independent encoding units. © 2010 Wiley Periodicals, Inc., Inc.

Subfields: Cellular and Molecular Neuroscience, Cognitive Neuroscience, Developmental Neuroscience

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Cellular and Molecular Neuroscience

In Cognitive Neuroscience

In Developmental Neuroscience

Citations in the corpus

Adult Neurogenesis in the Mammalian Brain: Significant Answers and Significant Questions (2011, background): “In contrast, Prox1 (Lavado et al., 2010), NeuroD (Gao et al., 2009; Kuwabara et al., 2009), and Krü ppel-like factor 9 (Scobie et al., 2009) are sequentially required for maturation and survival of new neurons in the adult hippocampus.”
Pattern separation: a common function for new neurons in hippocampus and olfactory bulb (2011, background): “Neurocognitive testing and fMRI studies in humans have also suggested a role for the DG in pattern separation (Bakker et al., 2008; Lacy et al., 2010).”
Adult Neurogenesis in the Hippocampus: From Stem Cells to Behavior. (2016, unknown): “However, some studies of DG activity have found that newborn cells contribute to a decrease in DG network activity (Ikrar et al., 2013; Lacefield et al., 2012).”
Modification of hippocampal circuitry by adult neurogenesis (2012, background): “In vivo recording from the adult mouse dentate gyrus showed that elimination of newborn neurons leads to a marked increase in the spontaneous gamma-frequency burst amplitude in the dentate gyrus and hilus, supporting a role of adult-born neurons in inhibiting recurrent network activity in the dentat”
Distinct Contribution of Adult-Born Hippocampal Granule Cells to Context Encoding (2016, unknown): “There is indeed evidence from ablation studies that abGCs may modulate the activity of mGCs, possibly via their influence on the DG microcircuit (Burghardt et al., 2012; Drew et al., 2015; Ikrar et al., 2013; Lacefield et al., 2012; Park et al., 2015).”
Functional Dissociation of Adult-Born Neurons Along the Dorsoventral Axis of the Dentate Gyrus (2014, background): “…ventral hippocampus and that adult-born neurons functionally integrate into, and are indistinguishable from, the surrounding network as they mature (Laplagne et al., 2006; Toni et al., 2008), it has been hypothesized that dorsal and ventral subpopulations of adult-born neurons respectively…”
Hippocampal Memory Traces Are Differentially Modulated by Experience, Time, and Adult Neurogenesis (2014, background): “The unique properties of young adult-born hippocampal neurons are likely responsible for their impact on the transmis- sion of information from the DG to CA3 (Lacefield et al., 2012; Marı́n-Burgin et al., 2012).”