Rishikesh Narayanan

Plasticity degeneracy underlies flexible formation and reconfiguration of spatial representations in hippocampal granule cells

The paper shows that flexible spatial representations in hippocampal granule cells arise from multiple non-random plasticity mechanisms rather than a single unique rule.

Stochastic resonance in the impact of afferent sensory noise on grid-patterned firing and path integration in a continuous attractor network

This study investigates how sensory noise affects grid-patterned firing and path integration in a continuous attractor network, finding that low levels of noise can enhance performance through stochastic resonance.

Intrinsic excitability of rat hippocampal granule cells increases along the dorsal-to-ventral axis

This study examines the electrophysiological properties of rat hippocampal granule cells along the dorsoventral axis, finding increased excitability and blade-specific firing rate differences.

HCN channels enhance synchrony propagation in heterogeneous synfire chains

This study identifies HCN channels as enhancers of synchrony propagation in heterogeneous synfire chains under noisy conditions.

Spatial information transfer in recurrent place-cell networks depends on excitation-inhibition balance, neural-circuit heterogeneities, and trial-to-trial variability

The paper shows how excitation-inhibition balance, neural heterogeneities, and trial-to-trial variability jointly regulate spatial information transfer in recurrent place-cell networks.

Task-dependence of network-to-network variability in learning, performance, and dynamics of heterogeneous recurrent networks

The paper investigates how task-dependent variability arises in artificial recurrent networks with intrinsic heterogeneities, showing functional degeneracy and non-monotonic relationships between heterogeneity, task demands, and performance.

Transcription factor LHX2 suppresses astrocyte proliferation in the postnatal mammalian cerebral cortex

This study shows that loss of Lhx2 increases astrocyte proliferation in upper cortical layers and induces reactive gliosis-like signatures without injury.

Diversity in the impact of heterogeneities on recurrent networks performing a cognitive task

This study assesses how different levels of heterogeneity affect the performance and dynamics of recurrent neural networks trained on a cognitive task.

Degeneracy explains diversity in interneuronal regulation of pattern separation in heterogeneous dentate gyrus networks

The paper shows that divergent feedforward connectivity alone does not ensure pattern separation in dentate gyrus networks, highlighting the critical role of interneurons and local connectivity.

Ion-channel degeneracy and heterogeneities in the emergence of signature physiological characteristics of dentate gyrus granule cells

The paper shows that dentate gyrus granule cell physiology arises from non-random, degenerate ion-channel combinations rather than a single deterministic model.

Dichotomy between extracellular signatures of active dendritic chemical synapses and gap junctions

The paper investigates how gap junctions and chemical synapses differentially shape extracellular potentials through computational modeling and electrophysiological analysis.

Cross-strata co-occurrence of ripples with theta-frequency oscillations in the hippocampus of foraging rats

The paper quantifies co-occurrence of ripples with theta oscillations across hippocampal strata in foraging rats, finding theta ripples occur in ~20% of ripple events and show theta-phase preferences.

LHX2 regulates dendritic morphogenesis in layer II/III of the neocortex via distinct pathways in progenitors and postmitotic neurons.

HCN channels enhance robustness of patterned activity propagation in heterogeneous conductance-based ring networks

The paper shows that HCN channels enhance robustness of patterned activity propagation in heterogeneous neural networks by introducing a slow negative feedback loop.

Plasticity manifolds and ion-channel degeneracy govern circadian oscillations of neuronal intrinsic properties in the suprachiasmatic nucleus

The paper investigates how SCN neurons maintain circadian oscillations despite ion channel variability, revealing ion-channel degeneracy and a plasticity manifold that enable stable transitions.

Stochastic resonance and bifurcations in a heterogeneous neuronal population explain intrinsic oscillatory patterns in entorhinal cortical stellate cells

This study shows that heterogeneous stochastic bifurcations in stellate cells explain peri-threshold oscillations and why theta oscillations may not be observed in vivo.

Ion-channel degeneracy and heterogeneities in the emergence of complex spike bursts in CA3 pyramidal neurons

The paper investigates how intrinsic and synaptic heterogeneities affect complex spike bursting in CA3 pyramidal neurons using computational models.

Dominant role of adult neurogenesis-induced structural heterogeneities in driving plasticity heterogeneity in dentate gyrus granule cells

Plasticity manifolds: Conjunctive changes in multiple ion channels mediate activity-dependent plasticity in hippocampal granule cells

The paper investigates how theta burst firing affects intrinsic plasticity in rat DG granule cells, revealing conjunctive changes in multiple ion channels.

Resonating neurons stabilize heterogeneous grid-cell networks

This study shows that resonating neurons stabilize grid-cell networks against biological heterogeneities by suppressing low-frequency perturbations.

Spatial information transfer in hippocampal place cells depends on trial-to-trial variability, symmetry of place-field firing and biophysical heterogeneities

The paper investigates how trial-to-trial variability, place-field symmetry, and biophysical properties affect spatial information transfer in hippocampal place cells using computational models.

Ion-channel regulation of response decorrelation in a multi-scale model of the dentate gyrus

This study investigates how eliminating individual ion channels affects network-scale response decorrelation in a multi-scale model of the dentate gyrus, revealing differential impacts based on biological heterogeneities.

Efficient phase coding in hippocampal place cells

This study develops a model of hippocampal place cells to show how diverse intrinsic and synaptic properties can achieve efficient phase coding and excitability homeostasis through parametric degeneracy.

Heterogeneities in intrinsic excitability and frequency-dependent response properties of granule cells across the blades of the rat dentate gyrus

This study identifies physiological heterogeneities in granule cells across different sectors of the rat dentate gyrus, showing distinct intrinsic excitability and response properties.

Robust emergence of sharply tuned place cell responses in hippocampal neurons with structural and biophysical heterogeneities

This study shows that sharp place-field tuning in hippocampal neurons emerges despite structural and biophysical variability through mechanisms like synaptic democracy and ion-channel degeneracy.

Degeneracy in hippocampal physiology and plasticity

This review explores degeneracy in hippocampal physiology and plasticity, cataloging evidence and proposing its role in balancing encoding and homeostasis.

Heterogeneities in afferent connectivity dominate local heterogeneities in the emergence of response decorrelation in the dentate gyrus

The paper investigates how different types of heterogeneities contribute to response decorrelation in the dentate gyrus, finding that afferent heterogeneities dominate over local ones.

Spatially dispersed synapses yield sharply-tuned place cell responses through dendritic spike initiation

The paper shows that sharp place cell responses can arise from randomly dispersed iso-feature synapses, relying on dendritic channels and NMDA receptors, challenging previous assumptions about synaptic clustering.

Degeneracy in the robust expression of spectral selectivity, subthreshold oscillations and intrinsic excitability of entorhinal stellate cells

The paper assesses how channel heterogeneities in entorhinal stellate cells affect the robustness of electrophysiological properties, revealing cellular-scale degeneracy and efficient coding mechanisms.