Paul S. Katz

Professor and Director of Neuroscience

Photograph of Paul Katz
412 Morrill Science Center, Bldg III

B.A., Northwestern University, 1982 M.S., Northwestern University, 1982 Ph.D., Cornell University, 1989


Brandeis University, 1989 - 1992

Research Interests: 

Evolution, Development, and Function of Neural Circuits underlying Behavior

Our lab is interested in neural circuits underlying rhythmic motor behavior. We use sea slugs (Mollusca, Gastropoda, Heterobranchia, Nudipleura) because they have fairly simple brains with only 10,000 neurons and simple behaviors. The neurons are individually identifiable, allowing us to fully understand the neural mechanisms for these behaviors at the cellular level. Furthermore, because there are many species that have homologous neurons. We can compare the neural circuits in these species to learn about the evolution of neural circuits and behavior. We are also examining the development of the neural circuits to understand how homologous neurons come to differ in properties and connectivity. The lab uses a wide variety of techniques including intracellular electrophysiology, tracer staining, immunohistochemistry, in situ hybridization, single neuron RNA-seq, bioinformatics, computational simulations, and 3-D electron microscopic reconstruction of neural connections.

Representative Publications: 

Katz PS (2019) My Word: The conservative bias of life scientists. Current Biology, 29, R663–R682. PMID:31336077 Sakurai A, Katz PS. (2019) Command or obey? Homologous neurons differ in hierarchical position for the generation of homologous behaviors. J Neurosci. pii: 3229-18. doi: 10.1523/JNEUROSCI.3229-18.2019. [Epub ahead of print] PubMed PMID: 31209170. Katz PS and Quinlan PD (2019) The importance of identified neurons in gastropod molluscs to neuroscience, Current Opinion in Neurobiology, v56.

Cook GM, Gruen AE, Morris J, Pankey MS, Senatore A, Katz, P.S., Watson WH, Newcomb JM (2018) Sequences of circadian clock proteins in the nudibranch mollusks Hermissenda crassicornis, Melibe leonina, and Tritonia diomedea. Biol Bull. 234, 207-218.

Tamvacakis AN, Senatore A, and Katz, P.S. (2018) Single neuron serotonin receptor subtype gene expression correlates with behaviour within and across three molluscan species. Proc. Royal Soc. B 285: 20180791;

Gunaratne, C.A., Sakurai, A., Katz, P.S. 2017. Variations on a theme: Species differences in synaptic connectivity do not predict central pattern generator activity. Journal of Neurophysiology. 118(2): 1123-1132, DOI: 10.1152/jn.00203.2017.

Sakurai, A., Katz, P.S. 2017. Artificial synaptic rewiring demonstrates that distinct neural circuit configurations underlie homologous behaviors. Current Biology. 27(12): 1721–1734.e3 DOI:

Katz, P.S., Hale, M.E. 2017. Chapter 6: Evolution of motor systems. In Fundamental concepts and new directions in motor control. Hooper SL, Büschges A (eds). pp 135-176. Wiley: Hoboken, NJ. ISBN: 978-1-118-87340-3

Katz, P.S. and Sakurai, A. 2017. “Neural Control of Swimming in Nudipleura Molluscs”, Invertebrate Neuroscience Handbook. Byrne JH (ed), Oxford University Press, New York, NY.

Sakurai, A., Tamvacakis, A.N., and Katz, P.S. 2016. Recruitment of polysynaptic connections underlies functional recovery of a central pattern generator circuit after lesion. eNeuro, 3(4) DOI: 10.1523/ENEURO.0056-16.2016,

Sakurai, A. and Katz, P.S. 2016. The central pattern generator underlying swimming in Dendronotus iris: A simple half-center network oscillator with a twist. Journal of  Neurophysiology, 116(4): 1728-1742.

Katz, P.S. 2016. “Model organisms” in the light of evolution. Current Biology. 26 (14): pR649–R650. DOI:

Katz, P.S. 2016. Phylogenetic plasticity in the evolution of molluscan neural circuits. Current Opinion in Neurobiology. 41: 8-16.  doi:10.1016/j.conb.2016.07.004

Katz, P.S. 2016. Evolution of central pattern generators and rhythmic behaviours. Phil. Trans. Royal Soc. B., 371 (1685): 20150057.

Gunaratne, C.A. and Katz, P.S. 2016. Comparative mapping of GABA-immunoreactive neurons in the buccal ganglia of Nudipleura molluscs. Journal of Comparative Neurology. 524(6): 1181-92. PMID:26355705, DOI: 10.1002/cne.23895.

Tamvacakis, A.N., Senatore, A., Katz, P.S. 2015. Identification of genes related to learning and memory in the brain transcriptome of the mollusc, Hermissenda crassicornis. Learning and Memory, 22(12): 617-21

Sakurai, A., Katz, P.S. 2015. Phylogenetic and individual variation in gastropod central pattern generators. Journal of Comparative Physiology A, 201(9): 829-39.

Senatore, A., Edirisinghe, N., Katz, P.S. 2015. Deep mRNA sequencing of the Tritonia diomedea brain transcriptome provides access to gene homologues for neuronal excitability, synaptic transmission and peptidergic signalling. PLoS One, 10(2): e0118321. DOI:10.1371/journal.pone.0118321.

Sakurai, A., Gunaratne, C.A., Katz, P.S. 2014. Two interconnected kernels of reciprocally inhibitory interneurons underlie alternating left-right swim motor pattern generation in the mollusk Melibe leonine. Journal of Neurophysiology, 112(6): 1317-28. doi: 10.1152/jn.00261.2014. PMID: 24920032

Sakurai, A., Tamvacakis, A.N., Katz, P.S. 2014. Hidden synaptic differences in a neural circuit underlie differential behavioral susceptibility to a neural injury. eLife 10.7554/eLife.02598 PMID: 24920390

Katz, P.S. and Lillvis JL (2014) Reconciling the deep homology of neuromodulation with the evolution of behavior. Current Opinion in Neurobiology. 29: 39-47. PMID: 24878891

Gunaratne, C.A., Sakurai, A., and Katz, P.S. 2014. Comparative mapping of GABA-immunoreactive neurons in the central nervous systems of nudibranch molluscs. Journal of Comparative Neurology, 522(4): 794–810. PMID 24638845

Striedter, G.F., Belgard, T.G., Chen, C.C., Davis, F.P., Finlay, B.L., Güntürkün, O., Hale, M.E., Harris, J.A., Hecht, E.E., Hof, P.R., Hofmann, H.A., Holland, L.Z., Iwaniuk, A.N., Jarvis, E.D., Karten, H.J., Katz, P.S., Kristan, W.B., Macagno, E.R., Mitra, P.P., Moroz, L.L., Preuss, T.M., Ragsdale, C.W., Sherwood, C.C., Stevens, C.F., Stüttgen, M.C., Tsumoto, T., Wilczynski, W. 2014. NSF workshop report: Discovering general principles of nervous system organization by comparing brain maps across species. J. Comp. Neurol., 522(7): 1445-53. Co-published in Brain Behavior and Evolution, 31: 1-8.

Lillvis, J.L. and Katz, P.S. 2013. Parallel evolution of serotonergic neuromodulation underlies independent evolution of rhythmic motor behavior.  Journal of Neuroscience, 33(6): 2709-17.

Newcomb, J.M., Sakurai, A., Lillvis, J.L., Gunaratne, C.A., Katz, P.S. 2012. Homology and homoplasy of swimming behaviors and neural circuits in the Nudipleura (Mollusca, Gastropoda, Opisthobranchia). Proceedings of the National Academy of Sciences, 1090 Suppl 1: 10669-76. PMID: 22723353.

Lillvis, J.L., Gunaratne, C.A., Katz, P.S. 2012. Neurochemical and neuroanatomical identification of central pattern generator neuron homologues in Nudipleura molluscs. PLoS One, 7 (2): e31737, 2012.

Jhala, S., Tamvacakis, A.N., Katz, P.S. 2011. Toward locating the source of serotonergic axons in the tail nerve of Aplysia. Invertebrate Neuroscience, 11(2): 91-96. PMID: 21877137

Sakurai, A., Newcomb, J.M., Lillvis, J.L., Katz, P.S. 2011. Different roles for homologous interneurons in species exhibiting similar rhythmic behaviors. Current Biology, 21(12): 1036-1041. PMID: 21620707.

Katz, P.S. 2011. Neural mechanisms underlying the evolvability of behavior. Philosophical Transactions of the Royal Society of London B, 366 (1574): 2086-2099. 

Katz, P.S. 2010. The nature of neuroethology. Brain Behavior and Evolution, 73(3-4): 163-4 PMID: 21088378, DOI: 10.1159/000321719

Katz, P.S., Calin-Jageman, R.J., Dhawan, A., Frederick, C., Guo, S., Dissanayaka, R., Hiremath, N., Ma, W., Shen, X., Wang, H.C., Yang, H., Prasad, S., Sunderraman, R., Zhu, Y. 2010. NeuronBank: a tool for cataloging neuronal circuitry. Frontiers in Systems Neuroscience, 4: 9.