The research interests in the Saggau Lab are twofold: First, to understand the biophysics of central mammalian neurons that control both the communication between cells and their individual computational properties Second, to develop advanced optical imaging tools for studying living brain tissue that help us to achieve the first goal.
Our lab mainly focuses on synaptic transmission and dendritic integration. We have described the short-term modulation of voltage-dependent calcium channels (VDCCs) in presynaptic terminals, where the transient influx of Ca2+ determines the timing and amount of neurotransmitter release. We have also studied postsynaptic VDCCs and their modulation in dendritic spines, where transient Ca2+ elevations can trigger long-term changes in synaptic transmission, such as LTP and LTD. Further, we are probing dendritic signal integration by investigating spatio-temporal summation of individual synaptic inputs.
Techniques used in our lab to address these and other challenging Neuroscience issues include high-speed micro-photometry, as well as combined whole-cell patch clamp and confocal/multiphoton microscopy. We also employ realistic computational models that are constrained by the morphology of automatically reconstructed living neurons.
Our lab is actively involved in developing advanced optical techniques to overcome the technical difficulties inherent in stimulating and recording in the very fine structures of neuronal dendrites and synapses. We are developing imaging systems based on standing wave microscopy that support studying sub-resolution structures in living tissue. We have developed next generation optical stimulation and recording systems with improved spatio-temporal resolution based on multiphoton excitation by acousto-optic control of near infrared ultra-fast laser pulses. These advanced techniques are employed for three-dimensional structural and functional optical imaging in intact neural tissue and can provide new insights into normal and pathological brain function.
Losavio, B.E., Iyer, V., Patel, S., and Saggau, P. Acousto-optic laser scanning for multisite photo-stimulation of single neurons in vitro. Journal of Neural Engineering, 7:045002, 2010.
Losavio, B.E., Iyer, V., and Saggau, P. Two-photon microscope for multi-site micro-photolysis of caged neurotransmitters in acute brain slices. Journal of Biomedical Optics, 14:064033, 2009.
Gliko, O., Saggau, P., and Brownell, W.E. Compartmentalization of the outer hair cell demonstrated by slow diffusion in the extracisternal space. Biophysical Journal, 97:1215-1224, 2009.
Mancuso, J.J., Larson, A., Wensel, T.G., and Saggau, P. Multiphoton adaptation of a commercial low cost confocal microscope for live tissue imaging. Journal of Biomedical Optics, 14:034048, 2009.
Gliko, O., Brownell, W.E., and Saggau, P. Fast two-dimensional standing wave total internal reflection microscopy using acousto-optic deflectors. Optics Letters, 34 (6):836-838, 2009.
Losavio, B.E., Santamaria-Peng, A., Liang, Y., Kakadiaris, I.A., Colbert, C.M., and Saggau, P. Live neuron morphology automatically reconstructed from multiphoton and confocal imaging data. Journal of Neurophysiology, 100:2422-2429, 2008.
Reddy, G.D., Kelleher, K., Fink, R., and Saggau, P. Three-dimensional random access multiphoton microscopy for functional imaging of neuronal activity. Nature Neuroscience, 11:713-720, 2008.
Bansal, V, Patel, S., and Saggau, P. High-speed addressable confocal microscopy for functional imaging of cellular activity. Journal of Biomedical Optics, 11:034003, 2006.
Iyer, V., Hoogland, T., and Saggau, P. Fast functional imaging of single neurons using random-access multiphoton (RAMP) microscopy. Journal of Neurophysiology, 95:535-545, 2006.
Reddy, G.D. and Saggau, P. Fast three-dimensional scanning scheme using acousto-optic deflectors. Journal of Biomedical Optics, 10:064038, 2005.
Shown are different representations of data from a live neuron. The Raw Images are data obtained with a 3D imaging system developed in our lab. Using our automatic Reconstruction Pipeline, a realistic Model Structure is generated that can be utilized to simulate the neuron’s response to complex spatio-temporal stimulation pattern by means of a Computational Model. Such predicted neuronal responses can be used to guide complex imaging experiments and will increase the experimental success rate.
Ph.D., California Institute of Technology, 2004
Lab Collaborator Andy Groves, Ph.D.
The formation and differentiation of mechanosensory hair cells in the mammalian cochlea.
Kalpana Dokka, Ph.D.
Ph.D., University of Illinois at Chicago, 2009
Dora Angelaki, Ph.D.
How our brain integrates multiple sensory cues for the perception of spatial orientation.
Joseph G. Duman, Ph.D.
Ph.D., University of California, Berkeley, 2002
Lab Collaborator Kimberley R. Tolias, Ph.D.
Monomeric GTPases and interacting proteins in the development, maintenance, and plasticity of synapses and dendritic spines.
Henry Jerng, Ph.D.
Ph.D., Thomas Jefferson University, 1998
Lab Collaborator Paul J. Pfaffinger, Ph.D.
Molecular basis of functional variability among somatodendritic subthreshold transient K currents from different neuronal populations in the CNS and its influence on neuronal physiology.
Xiaolong Jiang, Ph.D.
Ph.D., Uniformed Services University of the Health Sciences, Bethesda MD., 2007 Lab Collaborator Andreas S. Tolias, Ph.D.
To decipher visual cortex neuronal circuitry at single-cell resolution with octuple whole cell recording and optogenetic stimulation.
Eliana M. Klier, Ph.D.
Ph.D., York University, Toronto, Ontario, Canada, 2003
Lab Collaborator Dora Angelaki, Ph.D.
My research examines how the brain uses information about eye and head position to keep track of objects in an environment that is constantly changing due to movements of the observer. One current study involves how we perceive visual stimuli and heading direction during smooth pursuit eye movements. Another study examines how we keep track of the location of objects in space during whole-body motion. Finally, I have also wanted to expand my experiments to patient populations and will soon begin to do so by examining how visual and vestibular information is processed in patients with traumatic brain injuries.
Sheng Liu, Ph.D.
Ph.D., Institute of Biophysics, Chinese Academy of Science, China, 2006
Lab Collaborator Dora E. Angelaki, Ph.D.
Neural mechanism of vestibular function, Computation Neuroscience, Neural basis of Self-motion.
Gonzalo Viana Di Prisco, Ph.D.
Ph.D., University of California, Berkeley, 1983
M.D., Central University of Venezuela, 1975
Lab Collaborator Mauro Costa-Mattioli, Ph.D.
Memory encoding: from synaptic to system consolidation. Mechanisms of memory guided locomotion and behavior.
T. Dorina Papageorgiou, Ph.D., M.H.Sc.
Ph.D., The University of Texas - M.D. Anderson Cancer Center, 2006
M.H.Sc., Johns Hopkins University, Bloomberg School of Public Health, 1997
Instructor of Neurology
Lab Collaborator Stelios M. Smirnakis, M.D., Ph.D.
To investigate cortical and subcortical plasticity in CNS-induced speech dysarthrias using brain-state classification in the real-time fMRI environment. To examine the mechanisms of recovery of visual perception in patients with area V1 and/or extrastriate cortical lesions using SVM classification in the real-time-fMRI, in an effort to enhance visual system plasticity and promote recovery of visual performance.
Saumil Patel, Ph.D.
Ph.D., University of Houston, Cullen College of Engineering, 1995
Lab Collaborator Andreas S. Tolias, Ph.D.
Research Interests Dynamic models and psychophysics of visual perception, eye movements and cognitive functions in humans: normals and patients with schizophrenia, Parkinson's and Huntington's disease.
Ari Rosenberg, Ph.D.
Ph.D., University of Chicago
Lab Collaborator Dora Angelaki, Ph.D.
My research interests include systems and computational neuroscience. More specifically, my work focuses on nonlinear encoding strategies implemented within the early visual system, the visual encoding of 3D object pose (position & orientation), and how the multisensory integration of visual and vestibular/proprioceptive signals give rise to the perceptual stability of visual experience.
Michael Shindler, Ph.D.
Ph.D., University of Texas Medical Branch at Galveston, 2003 Lab Collaborator Dora Angelaki, Ph.D.
To understand the way sensory information is used to perceive the world around us and our place in it. I focus on our perception of self-motion which allows us to update our knowledge about our location as well as our progress in getting to where we are going.
Keiichiro Susuki, M.D., Ph.D.
Ph.D., Yokohama City University School of Medicine, Japan, 2001
M.D., Yokohama City University School of Medicine, Japan, 1994
Lab Collaborator Matthew N. Rasband, Ph.D.
The role of cytoskeletal proteins at the nodes of Ranvier or Schwann cells and pathogenesis of autoimmune neuropathy (Guillain-Barré syndrome)
Ping Jun Zhu, Ph.D.
McGill University, 1997
Lab Collaborator Mauro Costa-Mattioli, Ph.D.
Roles of signaling pathways of translational control in synaptic plasticity and memory formation using biochemical, genetic, neurophysiological, and behavioral approaches; the effects of the signaling pathway on early gene expression, GABAergic transmission and other neuronal activities.