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37
Neural architecture of the electrosensory lateral line lobe: adaptations for coincidence detection, a sensory searchlight and frequency-dependent adaptive filtering
- J. Exp. Biol
, 1999
"... The electrosensory lateral line lobe (ELL) of weakly electric fish is the only nucleus that receives direct input from peripheral electroreceptor afferents. This review summarises the neurotransmitters, receptors and second messengers identified in the intrinsic circuitry of the ELL and the extrinsi ..."
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Cited by 28 (3 self)
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The electrosensory lateral line lobe (ELL) of weakly electric fish is the only nucleus that receives direct input from peripheral electroreceptor afferents. This review summarises the neurotransmitters, receptors and second messengers identified in the intrinsic circuitry of the ELL and the extrinsic descending direct and indirect feedback pathways, as revealed by recent in vitro and in vivo studies. Several hypotheses of circuitry function are examined on this basis and on the basis of recent functional evidence: (1) fast primary afferent excitatory postsynaptic potentials (EPSPs) and fast granule cell 2 GABAA inhibitory postsynaptic potentials (IPSPs) suggest the involvement of basilar pyramidal cells in coincidence detection; (2)
Ghostbursting: A Novel Neuronal Burst Mechanism
- JOURNAL OF COMPUTATIONAL NEUROSCIENCE
, 2002
"... Pyramidal cells in the electrosensory lateral line lobe (ELL) of weakly electric fish have been observed to produce high-frequency burst discharge with constant depolarizing current (Turner et al., 1994). We present a twocompartment model of an ELL pyramidal cell that produces burst discharges simil ..."
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Cited by 26 (7 self)
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Pyramidal cells in the electrosensory lateral line lobe (ELL) of weakly electric fish have been observed to produce high-frequency burst discharge with constant depolarizing current (Turner et al., 1994). We present a twocompartment model of an ELL pyramidal cell that produces burst discharges similar to those seen in experiments. The burst mechanism involves a slowly changing interaction between the somatic and dendritic action potentials. Burst termination occurs when the trajectory of the system is reinjected in phase space near the "ghost" of a saddlenode bifurcation of fixed points. The burst trajectory reinjection is studied using quasi-static bifurcation theory, that shows a period doubling transition in the fast subsystem as the cause of burst termination. As the applied depolarization is increased, the model exhibits first resting, then tonic firing, and finally chaotic bursting behavior, in contrast with many other burst models. The transition between tonic firing and burst firing is due to a saddle-node bifurcation of limit cycles. Analysis of this bifurcation shows that the route to chaos in these neurons is type I intermittency, and we present experimental analysis of ELL pyramidal cell burst trains that support this model prediction. By varying parameters in a way that changes the positions of both saddle-node bifurcations in parameter space, we produce a wide gallery of burst patterns, which span a significant range of burst time scales.
Conditional spike backpropagation generates burst discharge in a sensory neuron
- J. Neurophysiol
, 2000
"... generates burst discharge in a sensory neuron. J Neurophysiol 84: ..."
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Cited by 22 (2 self)
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generates burst discharge in a sensory neuron. J Neurophysiol 84:
Robustness and variability of neuronal coding by amplitude sensitive afferents in the weakly electric fish Eigenmannia
- Journal of Neurophysiology
, 2000
"... Koch, and Fabrizio Gabbiani. Robustness and variability of neuronal coding by amplitude-sensitive afferents in the weakly electric fish Eigenmannia. J Neurophysiol 84: 189–204, 2000. We investigated the variability of P-receptor afferent spike trains in the weakly electric fish, Eigenmannia, to repe ..."
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Cited by 17 (3 self)
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Koch, and Fabrizio Gabbiani. Robustness and variability of neuronal coding by amplitude-sensitive afferents in the weakly electric fish Eigenmannia. J Neurophysiol 84: 189–204, 2000. We investigated the variability of P-receptor afferent spike trains in the weakly electric fish, Eigenmannia, to repeated presentations of random electric field AMs (RAMs) and quantified its impact on the encoding of timevarying stimuli. A new measure of spike timing jitter was developed using the notion of spike train distances recently introduced by Victor and Purpura. This measure of variability is widely applicable to neuronal responses, irrespective of the type of stimuli used (deterministic vs. random) or the reliability of the recorded spike trains. In our data, the mean spike count and its variance measured in short time windows were poorly correlated with the reliability of P-receptor afferent spike trains, implying that such measures provide unreliable indices of trial-to-trial variability. P-receptor afferent spike trains were
Nonlinear information processing in a model sensory system.
- Journal of Neurophysiology,
, 2006
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Selectivity for multiple stimulus features in retinal ganglion cells.
- J. Neurophysiol.
, 2006
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Model of Gamma Frequency Burst Discharge Generated by Conditional Backpropagation
- J. NEUROPHYSIOL
, 2001
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Activity dynamics and behavioral correlates of CA3 and CA1 hippocampal pyramidal neurons
- Hippocampus
, 2012
"... ABSTRACT: The CA3 and CA1 pyramidal neurons are the major prin-cipal cell types of the hippocampus proper. The strongly recurrent col-lateral system of CA3 cells and the largely parallel-organized CA1 neu-rons suggest that these regions perform distinct computations. However, a comprehensive compari ..."
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Cited by 8 (2 self)
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ABSTRACT: The CA3 and CA1 pyramidal neurons are the major prin-cipal cell types of the hippocampus proper. The strongly recurrent col-lateral system of CA3 cells and the largely parallel-organized CA1 neu-rons suggest that these regions perform distinct computations. However, a comprehensive comparison between CA1 and CA3 pyramidal cells in terms of firing properties, network dynamics, and behavioral correla-tions is sparse in the intact animal. We performed large-scale recordings in the dorsal hippocampus of rats to quantify the similarities and differ-ences between CA1 (n> 3,600) and CA3 (n> 2,200) pyramidal cells during sleep and exploration in multiple environments. CA1 and CA3 neurons differed significantly in firing rates, spike burst propensity, spike entrainment by the theta rhythm, and other aspects of spiking dynamics in a brain state-dependent manner. A smaller proportion of CA3 than CA1 cells displayed prominent place fields, but place fields of CA3 neu-rons were more compact, more stable, and carried more spatial informa-tion per spike than those of CA1 pyramidal cells. Several other features of the two cell types were specific to the testing environment. CA3 neu-rons showed less pronounced phase precession and a weaker position versus spike-phase relationship than CA1 cells. Our findings suggest that these distinct activity dynamics of CA1 and CA3 pyramidal cells support their distinct computational roles. VC 2012 Wiley Periodicals, Inc. KEY WORDS: network dynamics; bursts; place cells; phase precession; firing rates
Persistent Na> current modifies burst discharge by regulating conditional backpropagation of dendritic spikes
- J. Neurophysiol
"... Persistent Na current modifies burst discharge by regulating condi-tional backpropagation of dendritic spikes. J Neurophysiol 89: 324–337, 2003; 10.1152/jn.00729.2002. The estimation and detection of stimuli by sensory neurons is affected by factors that govern a transition from tonic to burst mode ..."
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Cited by 6 (0 self)
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Persistent Na current modifies burst discharge by regulating condi-tional backpropagation of dendritic spikes. J Neurophysiol 89: 324–337, 2003; 10.1152/jn.00729.2002. The estimation and detection of stimuli by sensory neurons is affected by factors that govern a transition from tonic to burst mode and the frequency chracteristics of burst output. Pyramidal cells in the electrosensory lobe of weakly electric fish generate spike bursts for the purpose of stimulus detec-tion. Spike bursts are generated during repetitive discharge when a frequency-dependent broadening of dendritic spikes increases current flow from dendrite to soma to potentiate a somatic depolarizing afterpotential (DAP). The DAP eventually triggers a somatic spike doublet with an interspike interval that falls inside the dendritic refractory period, blocking spike backpropagiation and the DAP. Repetition of this process gives rise to a rhythmic dendritic spike failure, termed conditional backpropagation, that converts cell output from tonic to burst discharge. Through in vitro recordings and com-partmental modeling we show that burst frequency is regulated by the rate of DAP potentiation during a burst, which determines the time required to discharge the spike doublet that blocks backpropagation. DAP potentiation is maginfied through a postitve feedback process when an increase in dendritic spike duration activates persistent sodium current (INaP). INaP further promotes a slow depolarization that induces a shift from tonic to burst discharge over time. The results are consistent with a dynamical systems analysis that shows that the threshold separating tonic and burst discharge can be represented as a saddle-node bifurcation. The interaction between dendritic K current and INaP provides a physiological explanation for a variable time scale of bursting dynamics characteristic of such a bifurcation.
Impact of Geometrical Structures On the Output of Neuronal Models - From Spikes To Bursts
, 2000
"... What is the difference between the efferent spike train of a neuron with a large soma versus that of a neuron with a small soma? For both the two-compartment integrateand -fire (IF) model and the Pinsky-Rinzel (PR) model, we use a method we call the decoupling approach, to show that the smaller the ..."
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Cited by 5 (4 self)
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What is the difference between the efferent spike train of a neuron with a large soma versus that of a neuron with a small soma? For both the two-compartment integrateand -fire (IF) model and the Pinsky-Rinzel (PR) model, we use a method we call the decoupling approach, to show that the smaller the soma is, the faster and the more irregularly the neuron fires. Two limiting cases: the soma is much smaller than the dendrite or vise versa, are theoretically investigated. We further conclude, in terms of numerical simulations, that cells falling in between the two limiting cases form a continuum with respect to their firing properties (mean firing time and coefficient of variation of inter-spike intervals). As an application of our approach, we also find that when the soma is small, two-compartment models can be employed as slope detectors. Novel and rigorous results for the calculations of mean first exit time and bursting frequency are also included. 1 Introduction It is well documented...
