Spontaneous activity is an important regulator of network development throughout the nervous system. Activity produced in different parts of the developing nervous system shares many features, which suggests that it does not depend on the detailed architecture of developing networks but rather on their common properties. Insights into the mechanisms responsible for generating spontaneous activity have come from recent studies of the spinal cord. Developing spinal networks are hyperexcitable and their immature syn apses are subject to activity-dependent synaptic depression. The conjunction of these properties, which may be common throughout the developing nervous system, is responsible for the spontaneous, episodic activity expressed by spinal networks. These properties endow developing spinal networks with an extremely robust mechanism for generating spontaneous activity that is resistant to major pharmacological and surgical per turbations. NEUROSCIENTIST 5:41-47, 1999
Katz LC, Shatz CJSynaptic activity and the construction of cortical circuits. Science1996;274:1133-1138.
2.
Fields RD, Nelson PGActivity-dependent development of the vertebrate nervous system. Int Rev Neurobiol1992;34:133-214.
3.
Spitzer NCSpontaneous activity: functions of calcium transients in neuronal differentiation . Perspect Dev Neurobiol1995 ;2:379-386.
4.
Blanton MG, Knegstein ARSpontaneous action potential activity and synaptic currents in the embryonic turtle cerebral cortex. J Neurosci1991;11:3907-3923.
5.
Schwartz TH, Rabinowitz D., Unni V., Kumar VS, Smetters DK, Tsiola A., et al.Networks of coactive neurons in developing layer 1. Neuron1998;20:541-552.
6.
Garaschuk O. , Hanse E., Konnerth A.Developmental profile and synaptic origin of early network oscillations in the CA1 region of rat neonatal hippocampusJ Physiol1998;507:219-236.
7.
Lippe WRRelationship between frequency of spontaneous bursting and tonotopic position in the developing avian auditory system. Brain Res1995;703:205-213.
8.
Itaya SK, Fortm S., Molotchnikoff S.Evolution of spontaneous activity in the rat developing superior colliculus . Can J Pharmacol1994;73:1372-1377.
9.
Wong RO, Chernjavsky A., Smith SJ, Shatz CJEarly functional neural networks in the developing retina. Nature1995;374:716-718.
10.
Richter CP, Sauer G., Hoidis S., Klinke R.Development of activity patterns in auditory nerve fibers of pigeons . Hear Res1996;95: 77-86.
11.
Toutant JP, Toutant MN, Renaud D., Le Douann GHEnzymatic differentiation of muscle fiber types m embryonic latissimus dorsi of the chick: Effects of spinal cord stimulation. Cell Diff1979;8: 375-382.
12.
Persson M.The role of movements in the development of sutural and diarthrodial joints tested by long-term paralysis of chick embryos. J Anat1983;137:591-599.
13.
Hall BK, Herring SWParalysis and growth of the musculoskeletal system in the embryonic chick . J Morphol1990;206:45-56.
14.
Hamburger V.Some aspects of the embryology of behavior . Q Rev Biol1963;38:342.
15.
Bekoff A.Ontogeny of leg motor output in the chick embryo: a neural analysis . Brain Res1976;106:271-291.
16.
Landmesser LT, O'Donovan MJActivation patterns of embryonic chick hindlimb muscles recorded m-ovo and in an isolated spinal cord preparation . J Physiol1984;347:189-204.
Chub NL, Baev KVN-methyl-D-aspartate effect on spontaneous activity of 16-20 day old chick embryo spinal cord. Neirofiziologiya1991;23:205-13.
19.
Chub N., O'Donovan MJBlockade and recovery of spontaneous rhythmic activity following application of neurotransmitter antagonists to spinal networks of the chick embryo. J Neuroscience1998;18: 294-306.
20.
O'Donovan MJ , Landmesser LTThe development of hindlimb motor activity studied in an isolated preparation of the chick spinal cord. J Neurosci1987;7:3256-3264.
21.
Lee MT, O'Donovan MJOrganization of hindlimb muscle afferent projections to lumbosacral motoneurons in the chick embryo. J Neurosci1991;11:2564-2573.
22.
Mendelson B. , Frank E.Specific monosynaptic sensory-motor connections form in the absence of patterned neural activity and motoneuronal cell death . J Neurosci1991;11:1390-1403.
23.
Obata K., Oide M., Tanaka H.Excitatory and inhibitory actions of glycine on embryonic chick spinal neurons in culture. Brain Res1978;144:179-184.
24.
Wu W., Ziskind-Conhaim L., Sweet MAEarly development of glycine- and GABA- mediated synapses in rat spinal cord . J Neurosci1992;12:3935-3945.
25.
Sernagor E. , Chub N., Ritter A., O'Donovan MJPharmacological characterization of the rhythmic synaptic drive onto lumbosacral motoneurons in the chick embryo spinal cord . J Neurosci1995; 15:7452-7464.
26.
Nishimaru H. , Iizuka M., Ozaki S., Kudo N.Spontaneous motoneuronal activity mediated by glycine and GABA in the spinal cord of rat fetuses in vitro. J Physiol1996;497:131-143.
27.
Rohrbough J. , Spitzer NCRegulation of intracellular Cl- levels by Na(+)-dependent Cl- cotransport distinguishes depolarizing from hyperpotanzing GABAA receptor-mediated responses in spinal neurons. J Neurosci1996;16:82-91.
28.
Pockett S.Elimination of polyneuronal innervation in proximal and distal leg muscles of chick embryos. Brain Res1981;227:299-302.
29.
Thompson WJActivity and synapse elimination at the neuromuscular junctionCell Mol Neurobiol1985;5:167-182.
30.
Lohof AM, Delhaye-Bouchaud N., Manani J.Synapse elimination in the central nervous system: functional significance and cellular mechanisms. Rev Neurosci1986 ;7:85-101.
31.
Kalb RG, Lidow MS, Halsted MJ, Hockfield S.N-methyl-D-aspartate receptors are transiently expressed in the developing spinal cord ventral horn. Proc Natl Acad Sci U S A1992;89:8502-8506
32.
. Jakowec MW, Kalb RG, Martin LJ, Fox AJQuantitative and qualitative changes in AMPA receptor expression during spinal cord developmentNeuroscience1995;67:893-907.
33.
O'Donovan MJ , Ho S., Yee W.Calcium imaging of rhythmic network activity in the developing spinal cord of the chick embryo . J Neurosci1994;14:6354-6369.
34.
Fedirchuk B. , O'Donovan MJEvoked potentials are transiently depressed following rhythmic activity in the embryonic chick spinal cord . Soc Neurosci Abstr1996;22:1377.
35.
O'Donovan MJ , Chub N.Population behavior and self-organization in the genesis of spontaneous rhythmic activity by developing spinal networks . Sem Cell Dev Biol1997;8:21-28.
36.
O'Donovan MJ , Chub N., Wenner P.Mechanisms of spontaneous activity in developing spinal networksJ Neurobiol1998;37:131-145.
37.
Chub N., O'Donovan MJMulti-functional actions of GABA in the regulation of spontaneous activity in the isolated spinal cord of the chick embryo. Soc Neurosci Abstr1995;21:688
38.
. Dahm LM, Landmesser LTThe regulation of intramuscular nerve branching during normal development and following activity blockade. Dev Biol1988;130:621-644.
39.
O'Donovan MJ , Wenner P., Chub N., Tabak J., Rinzel J.Mechanisms of spontaneous activity in the developing spinal cord and their relevance to locomotion. New York Academy of Sciences. Neuronal Mechanisms for Generating Locomotor Activity. Ann NY Acad Sci1998 ;860:130-141.
40.
Barry M., O'Donovan MJThe effects of excitatory ammo acids and their antagonists on the generation of motor activity in the isolated chick cordDev Brain Res1987;36:271-6.
41.
Senn W., Wyler K., Streit J., et al.Dynamics of a random neural network with synaptic depression. Neural Networks1996;9:575-88.
42.
Tabak J., Senn W., O'Donovan MJ, Rinzel J.Comparison of two models for pattern generation based on synaptic depressionNeurocomputmg1999; in press.
43.
Ho S., O'Donovan MJRegionalization and inter-segmental coordination of rhythm generating networks in the spinal cord of the chick embryoJ Neurosci1993;13:1345-1371.
44.
Feller MB, Wellis DP, Stellwagen D., Werblin FS, Shatz CJRequirement for cholinergic synaptic transmission in the propagation of spontaneous retinal waves. Science1996 ;272:1182-1187.
45.
Ben-Ari Y., Cherubini E., Corradetti R., Gaiarsa J-L.Giant synaptic potentials in immature rat CA3 hippocampal neurons . J Physiol1989;416:303-325.
46.
Yuste R., Katz LCControl of postsynaptic Ca2+ influx in developmg neocortex by excitatory and inhibitory neurotransmitters. Neuron1991;6:333-344.
47.
Fischer KF, Lukasiewicz PD, Wong Rol.Age-dependent and cell class-specific modulation of retinal ganglion cell bursting activity by GABA. J Neurosci1998 ; 8:3767-3778.
48.
Tabak J., O'Donovan MJStatistical analysis and mtersegmental delays reveal possible roles of network depression in the generation of spontaneous activity in the chick embryo spinal cord. New York Academy of Sciences. Neuronal Mechanisms for Generating Locomotor Activity. Ann NY Acad Sci1998;860:428-431.
49.
Penn AA, Riquelme PA, Feller MB, Shatz CJCompetition in retinogeniculate patterning driven by spontaneous activity . Science1998;279:2108-2112.
