Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
???displayArticle.abstract???
The ability of brief stimuli to trigger prolonged neuronal activity is a fundamental requirement in nervous systems, common to motor responses and short-term memory. Bistable membrane properties and network feedback excitation have both been proposed as suitable mechanisms to sustain such persistent responses. There is now good experimental evidence for membrane bistability. In contrast, the long-standing hypotheses based on positive feedback excitation have yet to be supported by direct evidence for mutual excitatory connections between appropriate neurons. In young frog tadpoles (Xenopus), we show that a small region of caudal hindbrain and rostral spinal cord is sufficient to generate prolonged swimming in response to a brief stimulus. We used paired whole-cell patch recordings to identify hindbrain neurons in this region that actively excite spinal neurons to drive sustained swimming. We show directly that some of these hindbrain neurons make reciprocal excitatory connections with each other. We use a population model of the hindbrain network to illustrate how feedback excitation can provide a robust mechanism to generate persistent responses. Our recordings provide direct evidence for feedback excitation among neurons within a network that drives a prolonged response. Its presence in a lower brain region early in development suggests that it is a basic feature of neuronal network design.
Aiken,
Xenopus embryonic spinal neurons recorded in situ with patch-clamp electrodes--conditional oscillators after all?
2003, Pubmed,
Xenbase
Aiken,
Xenopus embryonic spinal neurons recorded in situ with patch-clamp electrodes--conditional oscillators after all?
2003,
Pubmed
,
Xenbase
Aksay,
In vivo intracellular recording and perturbation of persistent activity in a neural integrator.
2001,
Pubmed
Bass,
Sexual dimorphisms in the vocal control system of a teleost fish: morphology of physiologically identified neurons.
1990,
Pubmed
Brocard,
Differential contribution of reticulospinal cells to the control of locomotion induced by the mesencephalic locomotor region.
2003,
Pubmed
Butt,
EphA4 defines a class of excitatory locomotor-related interneurons.
2005,
Pubmed
Collins,
Sustained contractions produced by plateau-like behaviour in human motoneurones.
2002,
Pubmed
Cymbalyuk,
Bursting in leech heart interneurons: cell-autonomous and network-based mechanisms.
2002,
Pubmed
Dale,
Dual-component amino-acid-mediated synaptic potentials: excitatory drive for swimming in Xenopus embryos.
1985,
Pubmed
,
Xenbase
Del Negro,
Sodium and calcium current-mediated pacemaker neurons and respiratory rhythm generation.
2005,
Pubmed
Di Prisco,
Role of sensory-evoked NMDA plateau potentials in the initiation of locomotion.
1997,
Pubmed
Di Prisco,
A cellular mechanism for the transformation of a sensory input into a motor command.
2000,
Pubmed
Durstewitz,
Neurocomputational models of working memory.
2000,
Pubmed
Fraser,
Cholinergic-dependent plateau potential in hippocampal CA1 pyramidal neurons.
1996,
Pubmed
Garcia-Rill,
The mesencephalic locomotor region. II. Projections to reticulospinal neurons.
1987,
Pubmed
Goldman-Rakic,
Cellular basis of working memory.
1995,
Pubmed
HODGKIN,
A quantitative description of membrane current and its application to conduction and excitation in nerve.
1952,
Pubmed
Hounsgaard,
Serotonin-induced bistability of turtle motoneurones caused by a nifedipine-sensitive calcium plateau potential.
1989,
Pubmed
Kahn,
The central nervous origin of the swimming motor pattern in embryos of Xenopus laevis.
1982,
Pubmed
,
Xenbase
Kawasaki,
The African wave-type electric fish, Gymnarchus niloticus, lacks corollary discharge mechanisms for electrosensory gating.
1994,
Pubmed
Kiehn,
Plateau potentials and active integration in the 'final common pathway' for motor behaviour.
1991,
Pubmed
Koulakov,
Model for a robust neural integrator.
2002,
Pubmed
Lee,
Bistability in spinal motoneurons in vivo: systematic variations in rhythmic firing patterns.
1998,
Pubmed
Li,
Defining classes of spinal interneuron and their axonal projections in hatchling Xenopus laevis tadpoles.
2001,
Pubmed
,
Xenbase
Li,
Spinal inhibitory neurons that modulate cutaneous sensory pathways during locomotion in a simple vertebrate.
2002,
Pubmed
,
Xenbase
Li,
A direct comparison of whole cell patch and sharp electrodes by simultaneous recording from single spinal neurons in frog tadpoles.
2004,
Pubmed
,
Xenbase
Li,
Primitive roles for inhibitory interneurons in developing frog spinal cord.
2004,
Pubmed
,
Xenbase
Li,
Glutamate and acetylcholine corelease at developing synapses.
2004,
Pubmed
,
Xenbase
Loewenstein,
Bistability of cerebellar Purkinje cells modulated by sensory stimulation.
2005,
Pubmed
Major,
Persistent neural activity: prevalence and mechanisms.
2004,
Pubmed
Marder,
Principles of rhythmic motor pattern generation.
1996,
Pubmed
Matsuyama,
Locomotor role of the corticoreticular-reticulospinal-spinal interneuronal system.
2004,
Pubmed
McCormick,
Persistent cortical activity: mechanisms of generation and effects on neuronal excitability.
2003,
Pubmed
Mentis,
Noncholinergic excitatory actions of motoneurons in the neonatal mammalian spinal cord.
2005,
Pubmed
Metcalfe,
Segmental homologies among reticulospinal neurons in the hindbrain of the zebrafish larva.
1986,
Pubmed
Nishimaru,
Mammalian motor neurons corelease glutamate and acetylcholine at central synapses.
2005,
Pubmed
Noga,
Mechanism for activation of locomotor centers in the spinal cord by stimulation of the mesencephalic locomotor region.
2003,
Pubmed
Nordlander,
Development of early brainstem projections to the tail spinal cord of Xenopus.
1985,
Pubmed
,
Xenbase
Ohta,
Monosynaptic excitatory amino acid transmission from the posterior rhombencephalic reticular nucleus to spinal neurons involved in the control of locomotion in lamprey.
1989,
Pubmed
Peña,
Differential contribution of pacemaker properties to the generation of respiratory rhythms during normoxia and hypoxia.
2004,
Pubmed
Perrier,
Recruitment of motor neuronal persistent inward currents shapes withdrawal reflexes in the frog.
2005,
Pubmed
Peterson,
Reticulospinal connections with limb and axial motoneurons.
1979,
Pubmed
Prescott,
Four cell types with distinctive membrane properties and morphologies in lamina I of the spinal dorsal horn of the adult rat.
2002,
Pubmed
Roberts,
Descending projections and excitation during fictive swimming in Xenopus embryos: neuroanatomy and lesion experiments.
1986,
Pubmed
,
Xenbase
Roberts,
How does a nervous system produce behaviour? A case study in neurobiology.
1990,
Pubmed
,
Xenbase
Roberts,
Mutual Re-excitation with Post-Inhibitory Rebound: A Simulation Study on the Mechanisms for Locomotor Rhythm Generation in the Spinal Cord of Xenopus Embryos.
1990,
Pubmed
,
Xenbase
Roberts,
Motoneurons of the axial swimming muscles in hatchling Xenopus tadpoles: features, distribution, and central synapses.
1999,
Pubmed
,
Xenbase
Roberts,
Early functional organization of spinal neurons in developing lower vertebrates.
2000,
Pubmed
,
Xenbase
Satterlie,
Reciprocal inhibition and postinhibitory rebound produce reverberation in a locomotor pattern generator.
1985,
Pubmed
Seung,
Stability of the memory of eye position in a recurrent network of conductance-based model neurons.
2000,
Pubmed
Soffe,
Activity of commissural interneurons in spinal cord of Xenopus embryos.
1984,
Pubmed
,
Xenbase
Soffe,
Roles of Glycinergic Inhibition and N-Methyl-D-Aspartate Receptor Mediated Excitation in the Locomotor Rhythmicity of One Half of the Xenopus Embryo Central Nervous System.
1989,
Pubmed
,
Xenbase
Svirskis,
Transmitter regulation of plateau properties in turtle motoneurons.
1998,
Pubmed
Tunstall,
Modelling inter-segmental coordination of neuronal oscillators: synaptic mechanisms for uni-directional coupling during swimming in Xenopus tadpoles.
2002,
Pubmed
,
Xenbase
van Mier,
Structural and functional properties of reticulospinal neurons in the early-swimming stage Xenopus embryo.
1989,
Pubmed
,
Xenbase
Wang,
Synaptic reverberation underlying mnemonic persistent activity.
2001,
Pubmed
Wolf,
Non-linear summation of excitatory synaptic inputs to small neurones: a case study in spinal motoneurones of the young Xenopus tadpole.
1998,
Pubmed
,
Xenbase
Yoshida,
Axon projections of reciprocal inhibitory interneurons in the spinal cord of young Xenopus tadpoles and implications for the pattern of inhibition during swimming and struggling.
1998,
Pubmed
,
Xenbase
Zhao,
Longitudinal distribution of components of excitatory synaptic input to motoneurones during swimming in young Xenopus tadpoles: experiments with antagonists.
1998,
Pubmed
,
Xenbase