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???
Many neural circuits are capable of generating multiple stereotyped outputs after different sensory inputs or neuromodulation. We have previously identified the central pattern generator (CPG) for Xenopus tadpole swimming that involves antiphase oscillations of activity between the left and right sides. Here we analyze the cellular basis for spontaneous left-right motor synchrony characterized by simultaneous bursting on both sides at twice the swimming frequency. Spontaneous synchrony bouts are rare in most tadpoles, and they instantly emerge from and switch back to swimming, most frequently within the first second after skin stimulation. Analyses show that only neurons that are active during swimming fire action potentials in synchrony, suggesting both output patterns derive from the same neural circuit. The firing of excitatory descending interneurons (dINs) leads that of other types of neurons in synchrony as it does in swimming. During synchrony, the time window between phasic excitation and inhibition is 7.9 ± 1 ms, shorter than that in swimming (41 ± 2.3 ms). The occasional, extra midcycle firing of dINs during swimming may initiate synchrony, and mismatches of timing in the left and right activity can switch synchrony back to swimming. Computer modeling supports these findings by showing that the same neural network, in which reciprocal inhibition mediates rebound firing, can generate both swimming and synchrony without circuit reconfiguration. Modeling also shows that lengthening the time window between phasic excitation and inhibition by increasing dIN synaptic/conduction delay can improve the stability of synchrony.
Alford,
Endogenous activation of glycine and NMDA receptors in lamprey spinal cord during fictive locomotion.
1989, Pubmed
Alford,
Endogenous activation of glycine and NMDA receptors in lamprey spinal cord during fictive locomotion.
1989,
Pubmed
Beato,
Interaction between disinhibited bursting and fictive locomotor patterns in the rat isolated spinal cord.
1999,
Pubmed
Berkowitz,
Physiology and morphology of shared and specialized spinal interneurons for locomotion and scratching.
2008,
Pubmed
Berkowitz,
Spinal interneurons that are selectively activated during fictive flexion reflex.
2007,
Pubmed
Berkowitz,
Roles for multifunctional and specialized spinal interneurons during motor pattern generation in tadpoles, zebrafish larvae, and turtles.
2010,
Pubmed
,
Xenbase
Borisyuk,
Modeling the connectome of a simple spinal cord.
2011,
Pubmed
,
Xenbase
Borisyuk,
A developmental approach to predicting neuronal connectivity from small biological datasets: a gradient-based neuron growth model.
2014,
Pubmed
,
Xenbase
Briggman,
Multifunctional pattern-generating circuits.
2008,
Pubmed
Brown,
Abnormal oscillatory synchronisation in the motor system leads to impaired movement.
2007,
Pubmed
Buchanan,
Identification of interneurons with contralateral, caudal axons in the lamprey spinal cord: synaptic interactions and morphology.
1982,
Pubmed
Cazalets,
GABAergic control of spinal locomotor networks in the neonatal rat.
1998,
Pubmed
Clarke,
Neuroanatomical and functional analysis of neural tube formation in notochordless Xenopus embryos; laterality of the ventral spinal cord is lost.
1991,
Pubmed
,
Xenbase
Cohen,
Strychnine eliminates alternating motor output during fictive locomotion in the lamprey.
1984,
Pubmed
Colgin,
Oscillations and hippocampal-prefrontal synchrony.
2011,
Pubmed
Combes,
A switch in aminergic modulation of locomotor CPG output during amphibian metamorphosis.
2012,
Pubmed
,
Xenbase
Cowley,
Effects of inhibitory amino acid antagonists on reciprocal inhibitory interactions during rhythmic motor activity in the in vitro neonatal rat spinal cord.
1995,
Pubmed
Crone,
Genetic ablation of V2a ipsilateral interneurons disrupts left-right locomotor coordination in mammalian spinal cord.
2008,
Pubmed
Crone,
In mice lacking V2a interneurons, gait depends on speed of locomotion.
2009,
Pubmed
Dale,
Experimentally derived model for the locomotor pattern generator in the Xenopus embryo.
1995,
Pubmed
,
Xenbase
Dale,
Reciprocal inhibitory interneurones in the Xenopus embryo spinal cord.
1985,
Pubmed
,
Xenbase
Destexhe,
A model of spindle rhythmicity in the isolated thalamic reticular nucleus.
1994,
Pubmed
Dickinson,
Neuropeptide fusion of two motor-pattern generator circuits.
1990,
Pubmed
Doi,
Neuromodulation and the orchestration of the respiratory rhythm.
2008,
Pubmed
Elson,
Inhibitory synchronization of bursting in biological neurons: dependence on synaptic time constant.
2002,
Pubmed
Frigon,
Reconfiguration of the spinal interneuronal network during locomotion in vertebrates.
2009,
Pubmed
Getting,
Emerging principles governing the operation of neural networks.
1989,
Pubmed
Hagevik,
Coupling of spinal locomotor networks in larval lamprey revealed by receptor blockers for inhibitory amino acids: neurophysiology and computer modeling.
1994,
Pubmed
Higashijima,
Neurotransmitter properties of spinal interneurons in embryonic and larval zebrafish.
2004,
Pubmed
Jalil,
Fast reciprocal inhibition can synchronize bursting neurons.
2010,
Pubmed
Jefferys,
Neuronal networks for induced '40 Hz' rhythms.
1996,
Pubmed
Jing,
Generation of variants of a motor act in a modular and hierarchical motor network.
2005,
Pubmed
Jiruska,
Synchronization and desynchronization in epilepsy: controversies and hypotheses.
2013,
Pubmed
Jovanović,
Effects of inhibitory neurotransmitters on the mudpuppy (Necturus maculatus) locomotor pattern in vitro.
1999,
Pubmed
Kahn,
Experiments on the central pattern generator for swimming in amphibian embryos.
1982,
Pubmed
,
Xenbase
Kiehn,
Locomotor circuits in the mammalian spinal cord.
2006,
Pubmed
Kimura,
alx, a zebrafish homolog of Chx10, marks ipsilateral descending excitatory interneurons that participate in the regulation of spinal locomotor circuits.
2006,
Pubmed
Klein,
Flexibility of motor pattern generation across stimulation conditions by the neonatal rat spinal cord.
2010,
Pubmed
Kristan,
Neuronal control of leech behavior.
2005,
Pubmed
Kullander,
Ephrin-B3 is the midline barrier that prevents corticospinal tract axons from recrossing, allowing for unilateral motor control.
2001,
Pubmed
Kullander,
Role of EphA4 and EphrinB3 in local neuronal circuits that control walking.
2003,
Pubmed
Kupfermann,
Motor program selection in simple model systems.
2001,
Pubmed
Lanuza,
Genetic identification of spinal interneurons that coordinate left-right locomotor activity necessary for walking movements.
2004,
Pubmed
Li,
The control of locomotor frequency by excitation and inhibition.
2012,
Pubmed
,
Xenbase
Li,
Specific brainstem neurons switch each other into pacemaker mode to drive movement by activating NMDA receptors.
2010,
Pubmed
,
Xenbase
Li,
Reconfiguration of a vertebrate motor network: specific neuron recruitment and context-dependent synaptic plasticity.
2007,
Pubmed
,
Xenbase
Li,
Persistent responses to brief stimuli: feedback excitation among brainstem neurons.
2006,
Pubmed
,
Xenbase
Li,
Generation of locomotion rhythms without inhibition in vertebrates: the search for pacemaker neurons.
2011,
Pubmed
,
Xenbase
Liao,
Shared versus specialized glycinergic spinal interneurons in axial motor circuits of larval zebrafish.
2008,
Pubmed
Marder,
Invertebrate central pattern generation moves along.
2005,
Pubmed
Marder,
Understanding circuit dynamics using the stomatogastric nervous system of lobsters and crabs.
2007,
Pubmed
Marder,
Principles of rhythmic motor pattern generation.
1996,
Pubmed
Marder,
From biophysics to models of network function.
1998,
Pubmed
McLean,
A topographic map of recruitment in spinal cord.
2007,
Pubmed
McLean,
Continuous shifts in the active set of spinal interneurons during changes in locomotor speed.
2008,
Pubmed
Meyrand,
Dynamic construction of a neural network from multiple pattern generators in the lobster stomatogastric nervous system.
1994,
Pubmed
Meyrand,
Construction of a pattern-generating circuit with neurons of different networks.
1991,
Pubmed
Moult,
Fast silencing reveals a lost role for reciprocal inhibition in locomotion.
2013,
Pubmed
,
Xenbase
Norris,
A central pattern generator producing alternative outputs: temporal pattern of premotor activity.
2006,
Pubmed
Parker,
Complexities and uncertainties of neuronal network function.
2006,
Pubmed
Parker,
The activity-dependent plasticity of segmental and intersegmental synaptic connections in the lamprey spinal cord.
2000,
Pubmed
Popescu,
Highly dissimilar behaviors mediated by a multifunctional network in the marine mollusk Tritonia diomedea.
2002,
Pubmed
Quinlan,
Segmental, synaptic actions of commissural interneurons in the mouse spinal cord.
2007,
Pubmed
Rauscent,
Opposing aminergic modulation of distinct spinal locomotor circuits and their functional coupling during amphibian metamorphosis.
2009,
Pubmed
,
Xenbase
Ritter,
In vivo imaging of zebrafish reveals differences in the spinal networks for escape and swimming movements.
2001,
Pubmed
Roberts,
Can simple rules control development of a pioneer vertebrate neuronal network generating behavior?
2014,
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,
How neurons generate behavior in a hatchling amphibian tadpole: an outline.
2010,
Pubmed
,
Xenbase
Satou,
Functional role of a specialized class of spinal commissural inhibitory neurons during fast escapes in zebrafish.
2009,
Pubmed
Sautois,
Role of type-specific neuron properties in a spinal cord motor network.
2007,
Pubmed
Schnitzler,
Normal and pathological oscillatory communication in the brain.
2005,
Pubmed
Sharp,
Dynamic clamp: computer-generated conductances in real neurons.
1993,
Pubmed
Soffe,
Two distinct rhythmic motor patterns are driven by common premotor and motor neurons in a simple vertebrate spinal cord.
1993,
Pubmed
,
Xenbase
Soffe,
Defining the excitatory neurons that drive the locomotor rhythm in a simple vertebrate: insights into the origin of reticulospinal control.
2009,
Pubmed
,
Xenbase
Soffe,
Tonic and phasic synaptic input to spinal cord motoneurons during fictive locomotion in frog embryos.
1982,
Pubmed
,
Xenbase
Uhlhaas,
Neural synchrony in brain disorders: relevance for cognitive dysfunctions and pathophysiology.
2006,
Pubmed
Van Vreeswijk,
When inhibition not excitation synchronizes neural firing.
1994,
Pubmed
Wall,
A role for potassium currents in the generation of the swimming motor pattern of Xenopus embryos.
1994,
Pubmed
,
Xenbase
Wang,
Gamma oscillation by synaptic inhibition in a hippocampal interneuronal network model.
1996,
Pubmed
Wang,
Spindle rhythmicity in the reticularis thalami nucleus: synchronization among mutually inhibitory neurons.
1993,
Pubmed
Weimann,
Switching neurons are integral members of multiple oscillatory networks.
1994,
Pubmed
Weimann,
Neurons that form multiple pattern generators: identification and multiple activity patterns of gastric/pyloric neurons in the crab stomatogastric system.
1991,
Pubmed
White,
The same core rhythm generator underlies different rhythmic motor patterns.
2011,
Pubmed
White,
Synchronization and oscillatory dynamics in heterogeneous, mutually inhibited neurons.
1998,
Pubmed
Whittington,
Synchronized oscillations in interneuron networks driven by metabotropic glutamate receptor activation.
1995,
Pubmed
Wyart,
Optogenetic dissection of a behavioural module in the vertebrate spinal cord.
2009,
Pubmed
