Biological Sciences

< Back to list

Daniel Wagenaar

Title: Assistant Professor

SBBE, Neuroethology; Crossmodal sensory integration in invertebrates


  • Ph.D., California Institute of Technology, Pasadena, CA, 2006 (Physics).
  • M.Sc., King's College London, London, UK, 1998 (Information Processing and Neural Networks).
  • M.Sc., University of Amsterdam, Amsterdam, The Netherlands, 1997 (Physics).

Research Information

Research Interests

Obtaining information from the environment to guide behavior is one of the most fundamental functions of nervous systems. Most animals combine cues from multiple sensory modalities to gain information about their environments. When individual cues are not 100% reliable, combining cues greatly aids decision making and it makes behavior more robust under variable circumstances.

In healthy humans, sensory integration occurs effortlessly and rarely reaches consciousness. To give just one example, when you speak to me, I will tend to look at your face to get visual cues from your lips to assist my interpretation of the sound that I hear, and also to see your facial expression to help interpret the meaning behind your words. Yet, this effortlessness is compromised in some individuals with autism, schizophrenia, or certain developmental disorders.

At present, studying the basis for crossmodal sensory integration at the level of individual neurons is not practical in humans. Therefore, my lab uses the medicinal leech, Hirudo verbana, as a model animal. Adult leeches feed on mammalian blood. It lives on the bottom of shallow ponds. When a mammal steps into the water and splashes around, the leech will swim toward the source of the disturbance to find its prey. Leeches can find their prey in total darkness, relying on water-wave sensors on their skin. Remarkably, they can also find their prey using sensory stimuli alone: when placed in a shallow tank, they will swim toward a disturbance in a second tank placed above theirs but mechanically isolated from it. Under more general circumstances, cues from both modalities are available, and leeches must either combine the two modalities, or decide which one is more reliable and selectively ignore the other. The goal of my lab is to find out how their nervous system solves this challenge and produces a coherent decision for subsequent motion.

Hirudo is an ideal animal for such investigations, because of its reliable responses to visual and nonvisual stimuli, the simplicity and accessibility of its nervous system, and the robustness of its responses even after extreme surgery. Importantly, its visual system is quite primitive so its mechanism for multisensory integration is likely to be close to the most basic one possible; a good starting point for discovering fundamental properties that such a mechanism must have in order to be functional at all. Thus, elucidating this mechanism in great detail will suggest general properties for mechanisms of multisensory integration in other species and motivate experiments to further explore the far more complex integration that occurs in higher brains.

Please visit the lab’s website: I have positions available for graduate students.

Research Support

  • (PI), Wagenaar, Career Award at the Scientific Interface, Burroughs Wellcome Fund. 500k. 2009 to 2016. Status: Active.
  • (PI), Wagenaar, Daniel, Career Award at the Scientific Interface, Burroughs Wellcome Fund. (Career Award), $360,000.00. 08/15/2013 to 07/31/2016. Status: Awarded.
  • (PI), Wagenaar, Daniel, Elucidating interactions between behavior-generating circuits using functional and anatomical connectomics, National Institute of Neurological Disorders and Stroke. (R01NS094403), $337,365.00. 09/30/2015 to 06/30/2020. Status: Awarded.


Peer Reviewed Publications

  • P. L. Baljon and D. A. Wagenaar, 2015. Responses to conflicting stimuli in a simple stimulus–response pathway. J Neurosci 35, 2398-2406
  • J. M. Nagarah, A. Stowasser, R. Parker, H. Asari, and D. A. Wagenaar, 2015. Optically transparent multi–suction electrode arrays. Front. Neurosci. 9, art. no. 384.
  • D. A. Wagenaar, 2015. A classic model animal in the 21st century: recent lessons from the leech nervous system. J. Exp. Biol. 218, 3353-3359.
  • C. M. Harley and D. A. Wagenaar, 2014. Scanning behavior in the medicinal leech Hirudo verbana. PLoS ONE 9(1), e86120.
  • D. A. Wagenaar, 2014. Publication quality 2D graphs with less manual effort due to explicit use of dual coordinate systems. Source Code for Biology and Medicine, 9:22
  • S. Romanenko, P. H. Siegel, D. A. Wagenaar, and V. Pikov, 2014. Effects of millimeter wave irradiation and equivalent thermal heating on the activity of individual neurons in the leech ganglion. J Neurophysiol., jn.00357.2014.
  • C. M. Harley, M. Rossi, J. Cienfuegos, and D. A. Wagenaar, 2013. Discontinuous locomotion and prey sensing in the leech. J. Exp. Biol. 216, 1890–1897.
  • J. M. Nagarah and D. A. Wagenaar, 2012. Ultradeep fused silica glass etching with an HF-resistant photosensitive resist for optical imaging applications. J. Micromech. Microeng. 22(3), 035011.
  • D. A. Wagenaar, 2012. An optically stabilized fast-switching light emitting diode as a light source for functional neuroimaging. PLoS ONE 7(1), e29822.
  • C. M. Harley, J. Cienfuegos, and D. A. Wagenaar, 2011. Developmentally regulated multisensory integration for prey localization in the medicinal leech. J. Exp. Biol. 214, 3801–3807.
  • D. A. Wagenaar, R. Gonzalez, D. C. Ries, W. B. Kristan, and K. A. French, 2010. Alpha-conotoxin ImI disrupts central control of swimming in the medicinal leech. Neurosci. Lett. 485, 151–156.
  • D. A. Wagenaar, M. S. Hamilton, T. Huang, W. B. Kristan, and K. A. French, 2010. A hormone-activated central pattern generator for courtship. Curr. Biol. 20(6), 487–495.
  • D. A. Wagenaar and W. B. Kristan, 2010. Automated video analysis of animal movements using Gabor orientation filters. Neuroinform. 8(1), 33–42.
  • S. M. Baca*, A. Marin-Burgin*, D. A. Wagenaar*, and W. B. Kristan, 2008. Widespread inhibition proportional to excitation controls the gain of a leech behavioral circuit. Neuron 57(2), 276–289.
  • D. L. Fortin, M. R. Banghart, T. W. Dunn, K. Borges, D. A. Wagenaar, Q. Gaudry, M. H. Karakossian, T. S. Otis, W. B. Kristan, D. Trauner, and R. H. Kramer, 2008. Photochemical control of endogenous ion channels and cellular excitability. Nat. Methods 5(4), 331–338.
  • J. D. Rolston, D. A. Wagenaar, and S. M. Potter, 2007. Precisely timed spatiotemporal patterns of neural activity in dissociated cortical cultures. Neurosci. 148(1), 294–303.
  • D. A. Wagenaar, Z. Nadasdy, and S. M. Potter, 2006. Persistent dynamic attractors in activity patterns of cultured neuronal networks. Phys. Rev. E 73, art. no. 051907.
  • D. A. Wagenaar, J. Pine, and S. M. Potter, 2006. An extremely rich repertoire of bursting patterns during the development of cortical cultures. BMC Neurosci. 7, art. no. 11.
  • D. A. Wagenaar, J. Pine, and S. M. Potter, 2006. An extremely rich repertoire of bursting patterns during the development of cortical cultures. BMC Neurosci. 7, art. no. 11.
  • D. A. Wagenaar, J. Pine, and S. M. Potter, 2006. Searching for plasticity in dissociated cortical cultures on multi-electrode arrays. J. Negat. Results BioMed. 5, art. no. 16.
  • D. A. Wagenaar, R. Madhavan, J. Pine, and S. M. Potter, 2005. Controlling bursting in cortical cultures with closed-loop multi-electrode stimulation. J. Neurosci. 25(3), 680–688.
  • Z. C. Chow, D. J. Bakkum, D. A. Wagenaar, and S. M. Potter, 2005. Effects of random external background stimulation on network synaptic stability after tetanization: a modeling study. Neuroinform. 3(3), 263–280.
  • C. Fonck, B. N. Cohen, R. Nashmi, P. Whiteaker, D. A. Wagenaar, N. Rodrigues-Pinguet, P. Deshpande, S. McKinney, S. Kwoh, J. Munoz, C. Labarca, A. C. Collins, M. J. Marks, and H. A. Lester, 2005. Novel seizure phenotype and sleep disruptions in knock-in mice with hypersensitive α4* nicotinic receptors. J. Neurosci. 25(49), 11396–11411.
  • D. A. Wagenaar and C. Adami, 2004. Influence of chance, history, and adaptation on digital evolution. Artif. Life 10(2), 181–190.
  • D. A. Wagenaar and S. M. Potter, 2004. A versatile all-channel stimulator for electrode arrays, with real-time control. J. Neural Eng. 1, 39–44.
  • D. A. Wagenaar, J. Pine, and S. M. Potter, 2004. Effective parameters for stimulation of dissociated cultures using multi-electrode arrays. J. Neurosci. Methods 138(1–2), 27–37.
  • D. A. Wagenaar and S. M. Potter, 2002. Real-time multi-channel stimulus artifact suppression by local curve fitting. J. Neurosci. Methods 120, 113–120.
  • T. B. DeMarse, D. A. Wagenaar, A. W. Blau, and S. M. Potter, 2001. The neurally controlled animat: Biological brains acting with simulated bodies. Auton. Robots 11(3), 305–310.

Conference/Workshop Proceedings

  • S. Romanenko, P. H. Siegel, D. A. Wagenaar, and V. Pikov, 2013. Comparison of the effects of millimeter wave irradiation, general bath heating, and localized heating on neuronal activity in the leech ganglion. Proc. SPIE Terahertz and ultrashort electromagnetic pulses for biomedical applications 8585, G. J. Wilmink and B. L. Ibey, eds., art. no. UNSP-85850N.

Experience & Service

Work Experience

  • 2008 to 2012, Broad Senior Research Fellow., Caltech., Pasadena CA.
  • 2012 to 2013, Senior Research Fellow., Caltech., Pasadena CA.

Post Graduate training and Education

  • 2005 to 2008, Postdoctoral Scholar,, University of California, San Diego..