One of the fundamental problems in neuroscience is understanding how circuit function arises from the intrinsic properties of individual neurons and their synaptic connections. Of particular interest to us today is the extent to which similar circuit outputs can be generated by multiple mechanisms, both in different individual animals, or in the same animal over its life-time. As an experimental preparation we exploit the advantages of the central pattern generating circuits in the crusctacean stomatogastric nervous system. Central pattern generators are groups of neurons found in vertebrate and invertebrate nervous systems responsible for the generation of specific rhythmic behaviors such as walking, swimming, and breathing. The central pattern generators in the stomatogastric ganglion (STG) of lobsters and crabs are ideal for many analyses because the STG has only about 30 large neurons, the connectivity is established, the neurons are easy to record from, and when the stomatogastric ganglion is removed from the animal, it continues to produce rhythmic motor patterns.

1. How do neuromodulators and neuromodulatory neurons reconfigure circuits so that the same group of neurons can produce a variety of behaviorally relevant outputs?
   
   
2. How can networks be both stable over the life-time of the animal despite ongoing turnover of membrane proteins such as channels and receptors? How is network stability maintained over long time periods? To what extent do similar network outputs result from different underlying mechanisms or solutions?

To address these questions we employ electrophysiological, biophysical, computational, anatomical, biochemical, and molecular techniques.

Recent Publications:

Swensen, A.M., Golowasch, J., Christie, A.E., Coleman, M.J., Nusbaum, M.P., and Marder, E. (2000) GABA and GABA responses in the stomatogastric ganglion of the crab, Cancer borealis. J. Exp. Biol., 203: 2075-2092. [abstract]

Richards, K.S. and Marder, E. (2000) The actions of crustacean cardioactive peptide on adult and developing stomatogastric ganglion motor patterns. J. Neurobiol. 44: 31-44. [abstract]

Swensen, A.M. and Marder, E. (2000) Multiple peptides converge to activate the same voltage-dependent current in a central pattern generating circuit. J. Neurosci. 20: 6752-6759. [abstract]

Marder, E. (2000) Colored Chalk. Current Biol., 10: R613. [pdf file]

Marder, E. (2000) Models identify hidden assumptions. Nature Neurosci. 3: 1198.

Marder, E. (2000) Motor pattern generation. Curr. Opin. Neurobiol. 10: 691-698. [abstract]

Nusbaum, M.P., Blitz, D.M., Swensen, A.M., Wood, D., and Marder, E. (2001) The roles of co-transmission in neural network modulation. TINS 24: 146-154. [abstract]

Marder, E. (2001) Moving rhythms. Nature, 410: 755.

Soto-Treviño, C., Thoroughman, K.A., Marder, E., and Abbott, L.F. (2001) Activity-dependent modification of inhibitory synapses in models of rhythmic neural networks. Nature Neuroscience, 4: 297-303. [abstract]

Swensen, A.M. and Marder, E. (2001) Modulators with convergent cellular actions elicit distinct circuit outputs. J. Neuroscience, 21: 4050-4058. [abstract]

Goldman, M.S., Golowasch, J., Marder, E., and Abbott, L.F. (2001) Global structure, robustness, and modulation of neuronal models. J. Neuroscience, 21: 5229-5238. [abstract]

Marder, E. and Bucher, D. (2001) Central pattern generators and the control of rhythmic movements. Current Biol., 11: R986-R996. [abstract]

Li, L., Pulver, S.R., Kelley, W.P., Thirumalai, V., Sweedler, J.V., and Marder, E. (2002) Orcokinin peptides in developing and adult crustacean stomatogastric nervous systems and pericardial organs. J. Comp. Neurol., 444:227-244.

Golowasch, J., Goldman, M., Abbott, L.F, and Marder, E. (2002) Failure of averaging in the construction of conductance-based neuron models. J. Neurophysiol., 87: 11291131. [abstract]

Thirumalai, V. and Marder, E. (2002) Colocalized neuropeptides activate a central pattern generator by acting on different circuit targets. J. Neuroscience, 22: 18741882. [abstract]

Pulver, S.R. and Marder, E. (2002) Neuromodulatory complement of the pericardial organ in the embryonic lobster, Homarus americanus. J. Comp. Neurol., 451: 79-90.

Marder, E. (2002) Non-mammalian models for studying neural development and function. Nature, 417: 318-321. [abstract]

Marder, E. and Thirumalai, V. (2002) Cellular, synaptic, and network effects of neuromodulation. Neural Networks, 15: 479-493. [abstract]

Marder, E. and Prinz, A.A. (2002) Modeling stability in neuron and network function: the role of activity in homeostasis. BioEssays, 24:1145-1154. [abstract]

Marder, E. and Prinz, A.A. (2003) Current Compensation in neuronal homeostasis. Neuron, 37: 2-4. [abstract]

Abbott, L.F., Thoroughman, K., Prinz, A., Thirumalai, V. and Marder, E. (2003) Activity-dependent modification of intrinsic and synaptic conductances in neurons and rhythmic networks. In Van Ooyen, A., ed. Modeling Neural Development (MIT Press, Cambridge MA).

Richards, K.S., Simon, D.J., Pulver, S.R., Beltz, B.S. and Marder, E. (2003) Serotonin in the developing stomatogastric system of the lobster, Homarus americanus. J. Neurobiol. 54: 380-392. [abstract]

Prinz, A.A., Thirumalai, V. and Marder, E. (2003) The functional consequences of changes in the strength and duration of synaptic inputs to oscillatory neurons. J. Neurosci. 23: 943-954. [abstract]

Pulver, S.R., Thirumalai, V., Richards, K.S. and Marder, E. (2003) Dopamine and histamine in the developing stomatogastric system of the lobster, Homarus americanus. J. Comp. Neurol 462: 400-414. [abstract]

Bucher, D., Thirumalai, V. and Marder, E. (2003) Axonal dopamine receptors activate peripheral spike initiation in a stomatogastric motor neuron. J. Neurosci., 23: 6866-6875. [abstract]

Luther, JA, Robie AA, Yarotsky J, Reina C, Marder E, and Golowasch J. (2003) Episodic Bouts of Activity Accompany Recovery of Rhythmic Output By a Neuromodulator- and Activity-Deprived Adult Neural Network. J. Neurophysiol. 90:2720-2730. [abstract] [download article]

Li, L., Kelley, W.P., Billimoria, C.P., Christie, A.E., Pulver, S.R., Sweedler, J.V., and Marder, E. (2003) Mass spectrometric investigation of the neuropeptide complement and release in the pericardial organs of the crab, Cancer borealis. J. Neurochem, 87: 642-656. [abstract]

Birmingham, J.T., Billimoria, C.P., DeKlotz, T.R., Stewart, R.A. and Marder, E. (2003) Differential and history dependent modulation of a stretch receptor in the stomatogastric system of the crab, Cancer borealis. J. Neurophysiol, 90: 3608 - 3616. [abstract]

Prinz, A.A., Billimoria, C.P, and Marder, E. (2003) An alternative to hand-tuning conductance-based models: construction and analysis of data bases of model neurons. J. Neurophysiol., 90:3998-4015. [abstract] [Download Article]

Christie, A.E., Stein, W., Quinlan, J.E., Beenhakker, M., Marder, E., and Nusbaum, M.P. (2003) Actions of a histaminergic/peptidergic projection neuron on rhythmic motor patterns in the stomatogastric nervous system of the crab, Cancer borealis. J. Comp. Neurol., 469:153 - 169 [abstract]

Mahadevan A, Lappe J, Rhyne RT, Cruz-Bermudez ND, Marder E, Goy MF. (2004) Nitric oxide inhibits the rate and strength of cardiac contractions in the lobster Homarus americanus by acting on the cardiac ganglion. J Neurosci. 24:2813-24. [abstract]

Prinz AA, Abbott LF, Marder E. (2004) The dynamic clamp comes of age. Trends Neurosci. 27:218-24.

Goaillard JM, Schulz DJ, Kilman VL, Marder E. (2004) Octopamine modulates the axons of modulatory projection neurons. J Neurosci. 24(32):7063-73. [abstract]

Pulver SR, Bucher D, Simon DJ, Marder E. (2004) Constant amplitude of postsynaptic responses for single presynaptic action potentials but not bursting input during growth of an identified neuromuscular junction in the lobster, Homarus americanus. J Neurobiol. 2005 Jan;62(1):47-61. [abstract]

Destexhe A, Marder E.(2004) Plasticity in single neuron and circuit computations. Nature. 431:789-95. [abstract]

Prinz AA, Bucher D, Marder E. (2004) Similar network activity from disparate circuit parameters. Nat Neurosci. 7:1345-52. [abstract]

Bucher D, Prinz AA, Marder E. (2005) Animal-to-animal variability in motor pattern production in adults and during growth. J Neurosci. 25:1611-9. [abstract]

Marder E, Rehm KJ.(2005) Development of central pattern generating circuits. Curr Opin Neurobiol. 15:86-93. [abstract]

Soto-Trevino C, Rabbah P, Marder E, Nadim F. (2005) A computational model of electrically coupled, intrinsically distinct pacemaker neurons. J Neurophysiol. 94:590-604. [abstract]

Marder E, Bucher D, Schulz DJ, Taylor AL. (2005) Invertebrate central pattern generation moves along, Curr Biol. 15:R685-99. [abstract]

Billimoria CP, Li L, Marder E. (2005) Profiling of neuropeptides released at the stomatogastric ganglion of the crab, Cancer borealis with mass spectrometry. J Neurochem. 95:191-9. [abstract]

Thirumalai V, Prinz AA, Johnson CD, Marder E. (2006) Red pigment concentrating hormone strongly enhances the strength of the feedback to the pyloric rhythm oscillator but has little effect on pyloric rhythm period. J Neurophysiol. 95:1762-70. [abstract]

Schulz DJ, Goaillard JM, Marder E. (2006) Variable channel expression in identified single and electrically coupled neurons in different animals, Nat Neurosci. 9:356-62. [abstract]

Cruz-Bermudez ND, Fu Q, Kutz-Naber KK, Christie AE, Li L, Marder E. (2006) Mass spectrometric characterization and physiological actions of GAHKNYLRFamide, a novel FMRFamide-like peptide from crabs of the genus Cancer. J Neurochem. 2006 May;97:784-99. [abstract]

Bucher D, Taylor AL, Marder E. (2006) Central pattern generating neurons simultaneously express fast and slow rhythmic activities in the stomatogastric ganglion. J Neurophysiol. 2006 Jun;95:3617-32. [abstract]

Taylor AL, Hickey TJ, Prinz AA, Marder E. (2006) Structure and visualization of high-dimensional conductance spaces. J Neurophysiol. 2006 Aug;96:891-905. [abstract]

Goaillard JM, Marder E. (2006) Dynamic clamp analyses of cardiac, endocrine, and neural function. Physiology (Bethesda). 2006 Jun; 21:197-207. Review. [abstract]

Billimoria CP, DiCaprio RA, Birmingham JT, Abbott LF, Marder E. (2006) Neuromodulation of spike-timing precision in sensory neurons. J Neurosci. 2006 May 31; 26:5910-9. [abstract]

Marder E, Goaillard JM. (2006) Variability, compensation and homeostasis in neuron and network function. Nat Rev Neurosci. 2006 Jul; 7:563-74. Review. [abstract]

Marder E, Bucher D. (2007) Understanding circuit dynamics using the stomatogastric nervous system of lobsters and crabs. Annu Rev Physiol. 2007; 69:291-316. [abstract]

Bucher D, Johnson CD, Marder E. (2007) Neuronal morphology and neuropil structure in the stomatogastric ganglion of the lobster, Homarus americanus. J Comp Neurol. 2007 Mar 10; 501:185-205. [abstract]

Mass spectrometric characterization and physiological actions of VPNDWAHFRGSWamide, a novel B type allatostatin in the crab, Cancer borealis. Fu Q, Tang LS, Marder E, Li L. J Neurochem. 2007 May;101:1099-107. [abstract]

Quantitative expression profiling of identified neurons reveals cell-specific constraints on highly variable levels of gene expression. Schulz DJ, Goaillard JM, Marder EE. Proc Natl Acad Sci U S A. 2007 Aug 7;104:13187-91. [abstract]

Multiple modulators act on the cardiac ganglion of the crab, Cancer borealis. Cruz-Bermúdez ND, Marder E. J Exp Biol. 2007 Aug;210(Pt 16):2873-84. [abstract]

How tightly tuned are network parameters? Insight from computational and experimental studies in small rhythmic motor networks. Marder E, Tobin AE, Grashow R. Prog Brain Res. 2007;165:193-200. [abstract]

Mass spectral comparison of the neuropeptide complement of the stomatogastric ganglion and brain in the adult and embryonic lobster, Homarus americanus. Cape SS, Rehm KJ, Ma M, Marder E, Li L. J Neurochem. 2008 May;105:690-702. [abstract]

Spectral analyses reveal the presence of adult-like activity in the embryonic stomatogastric motor patterns of the lobster, Homarus americanus. Rehm KJ, Taylor AL, Pulver SR, Marder E. J Neurophysiol. 2008 Jun;99:3104-22. [abstract]

The roads not taken. Marder E. Curr Biol. 2008 Sep 9;18:R725-R726.

Developmental regulation of neuromodulator function in the stomatogastric ganglion of the lobster, Homarus americanus. Rehm KJ, Deeg KE, Marder E. J Neurosci. 2008 Sep 24;28:9828-39. [abstract]

Electrical synapses: rectification demystified. Marder E. Curr Biol. 2009 Jan 13;19:R34-5. Review.

How multiple conductances determine electrophysiological properties in a multicompartment model. Taylor AL, Goaillard JM, Marder E. J Neurosci. 2009 Apr 29;29:5573-86. [abstract]

Mass spectrometric characterization and physiological actions of novel crustacean C-type allatostatins. Ma M, Szabo TM, Jia C, Marder E, Li L. Peptides. 2009 Sep;30:1660-8. [abstract]

Reliable neuromodulation from circuits with variable underlying structure. Grashow R, Brookings T, Marder E. Proc Natl Acad Sci U S A. 2009 Jul 14;106:11742-6. [abstract]

Correlations in ion channel mRNA in rhythmically active neurons. Tobin AE, Cruz-Bermúdez ND, Marder E, Schulz DJ. PLoS One. 2009 Aug 25;4:e6742. [abstract]

Functional consequences of animal-to-animal variation in circuit parameters. Goaillard JM, Taylor AL, Schulz DJ, Marder E.
Nat Neurosci. 2009 Nov;12:1424-30. [abstract]

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Last reviewed: February 9, 2010. E-mail comments or questions to the webmaster.