Fritjof Helmchen

Summary

Affiliation: University of Zurich
Country: Switzerland

Publications

  1. ncbi request reprint Deep tissue two-photon microscopy
    Fritjof Helmchen
    Department of Neurophysiology, Brain Research Institute, University of Zurich, CH 8057 Zurich, Switzerland
    Nat Methods 2:932-40. 2005
  2. ncbi request reprint Little strokes fill big oaks: a simple in vivo stain of brain cells
    Fritjof Helmchen
    Department of Neurophysiology, Brain Research Institute, University of Zurich, CH 8057 Zurich, Switzerland
    Neuron 53:771-3. 2007
  3. doi request reprint High-speed in vivo calcium imaging reveals neuronal network activity with near-millisecond precision
    Benjamin F Grewe
    Department of Neurophysiology, Brain Research Institute, University of Zurich, Switzerland
    Nat Methods 7:399-405. 2010
  4. doi request reprint Reorganization of cortical population activity imaged throughout long-term sensory deprivation
    David J Margolis
    Brain Research Institute, University of Zurich, Zurich, Switzerland
    Nat Neurosci 15:1539-46. 2012
  5. doi request reprint Distinct functional properties of primary and posteromedial visual area of mouse neocortex
    Morgane M Roth
    Department of Neurophysiology, Brain Research Institute, University of Zurich, CH 8057 Zurich, Switzerland
    J Neurosci 32:9716-26. 2012
  6. doi request reprint Two-photon imaging of spinal cord cellular networks
    Helge C Johannssen
    Department of Neurophysiology, Brain Research Institute, University of Zurich, Winterthurerstrasse 190, CH 8057 Zurich, Switzerland
    Exp Neurol 242:18-26. 2013
  7. doi request reprint Simultaneous BOLD fMRI and fiber-optic calcium recording in rat neocortex
    Kristina Schulz
    Department of Neurophysiology, Brain Research Institute, University of Zurich, Switzerland
    Nat Methods 9:597-602. 2012
  8. ncbi request reprint In vivo calcium imaging of neural network function
    Werner Göbel
    Department of Neurophysiology, Brain Research Institute, University of Zurich, Zurich, Switzerland
    Physiology (Bethesda) 22:358-65. 2007
  9. doi request reprint HelioScan: a software framework for controlling in vivo microscopy setups with high hardware flexibility, functional diversity and extendibility
    Dominik Langer
    Brain Research Institute, University of Zurich, Winterthurerstrasse 190, CH 8057 Zurich, Switzerland
    J Neurosci Methods 215:38-52. 2013
  10. pmc Neuron to astrocyte communication via cannabinoid receptors is necessary for sustained epileptiform activity in rat hippocampus
    Guyllaume Coiret
    Brain Research Institute, University of Zurich, Zurich, Switzerland
    PLoS ONE 7:e37320. 2012

Collaborators

Detail Information

Publications43

  1. ncbi request reprint Deep tissue two-photon microscopy
    Fritjof Helmchen
    Department of Neurophysiology, Brain Research Institute, University of Zurich, CH 8057 Zurich, Switzerland
    Nat Methods 2:932-40. 2005
    ..Here we review fundamental concepts of nonlinear microscopy and discuss conditions relevant for achieving large imaging depths in intact tissue...
  2. ncbi request reprint Little strokes fill big oaks: a simple in vivo stain of brain cells
    Fritjof Helmchen
    Department of Neurophysiology, Brain Research Institute, University of Zurich, CH 8057 Zurich, Switzerland
    Neuron 53:771-3. 2007
    ..Neuronal populations are sparsely labeled, preserving the ability to resolve calcium signals in dendrites and synaptic structures...
  3. doi request reprint High-speed in vivo calcium imaging reveals neuronal network activity with near-millisecond precision
    Benjamin F Grewe
    Department of Neurophysiology, Brain Research Institute, University of Zurich, Switzerland
    Nat Methods 7:399-405. 2010
    ..By revealing spike sequences in neuronal populations on a fast time scale, high-speed calcium imaging will facilitate optical studies of information processing in brain microcircuits...
  4. doi request reprint Reorganization of cortical population activity imaged throughout long-term sensory deprivation
    David J Margolis
    Brain Research Institute, University of Zurich, Zurich, Switzerland
    Nat Neurosci 15:1539-46. 2012
    ..Sensory-driven responsiveness is a key property controlling experience-dependent activity changes in individual neurons...
  5. doi request reprint Distinct functional properties of primary and posteromedial visual area of mouse neocortex
    Morgane M Roth
    Department of Neurophysiology, Brain Research Institute, University of Zurich, CH 8057 Zurich, Switzerland
    J Neurosci 32:9716-26. 2012
    ..Together, PM is tuned for cardinal orientations, high SFs, and low speed and is further located between V1 and the retrosplenial cortex consistent with a role in processing natural scenes during spatial navigation...
  6. doi request reprint Two-photon imaging of spinal cord cellular networks
    Helge C Johannssen
    Department of Neurophysiology, Brain Research Institute, University of Zurich, Winterthurerstrasse 190, CH 8057 Zurich, Switzerland
    Exp Neurol 242:18-26. 2013
    ..In this review we summarize recent results from these types of high-resolution two-photon imaging studies in the spinal cord and provide experimental perspectives for improving and extending this approach in future applications...
  7. doi request reprint Simultaneous BOLD fMRI and fiber-optic calcium recording in rat neocortex
    Kristina Schulz
    Department of Neurophysiology, Brain Research Institute, University of Zurich, Switzerland
    Nat Methods 9:597-602. 2012
    ..Our findings highlight the complexity of fMRI BOLD signals, involving both neuronal and glial activity. Combined fMRI and fiber-optic recordings should help to clarify cellular mechanisms underlying BOLD signals...
  8. ncbi request reprint In vivo calcium imaging of neural network function
    Werner Göbel
    Department of Neurophysiology, Brain Research Institute, University of Zurich, Zurich, Switzerland
    Physiology (Bethesda) 22:358-65. 2007
    ..In this review, we discuss basic aspects of in vivo calcium imaging and highlight recent developments that will help to uncover operating principles of neural circuits...
  9. doi request reprint HelioScan: a software framework for controlling in vivo microscopy setups with high hardware flexibility, functional diversity and extendibility
    Dominik Langer
    Brain Research Institute, University of Zurich, Winterthurerstrasse 190, CH 8057 Zurich, Switzerland
    J Neurosci Methods 215:38-52. 2013
    ..We recommend HelioScan as a convenient software framework for the in vivo imaging community...
  10. pmc Neuron to astrocyte communication via cannabinoid receptors is necessary for sustained epileptiform activity in rat hippocampus
    Guyllaume Coiret
    Brain Research Institute, University of Zurich, Zurich, Switzerland
    PLoS ONE 7:e37320. 2012
    ..Thus, endocannabinoid signaling from neurons to astrocytes represents an additional significant factor in the maintenance of epileptiform activity in the hippocampus...
  11. ncbi request reprint New angles on neuronal dendrites in vivo
    Werner Göbel
    Department of Neurophysiology, Brain Research Institute, Winterthurerstr 190, CH 8057, Zurich, Switzerland
    J Neurophysiol 98:3770-9. 2007
    ..These novel scanning modes will facilitate optical probing of dendritic function in vivo...
  12. doi request reprint Behaviour-dependent recruitment of long-range projection neurons in somatosensory cortex
    Jerry L Chen
    Brain Research Institute, University of Zurich, Winterthurerstrasse 190, CH 8057 Zurich, Switzerland
    Nature 499:336-40. 2013
    ..Sensory stimulus features alone were not sufficient to elicit these differences, suggesting that selective transmission of S1 information to S2 and M1 is driven by behaviour. ..
  13. pmc Post hoc immunostaining of GABAergic neuronal subtypes following in vivo two-photon calcium imaging in mouse neocortex
    Dominik Langer
    Department of Neurophysiology, Brain Research Institute, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
    Pflugers Arch 463:339-54. 2012
    ..Our approach is a general and flexible method to distinguish GABAergic subtypes in cell populations previously imaged in the living animal. It should thus facilitate dissecting the functional roles of these subtypes in neural circuitry...
  14. pmc In vivo Ca2+ imaging of dorsal horn neuronal populations in mouse spinal cord
    Helge C Johannssen
    Department of Neurophysiology, Brain Research Institute, University of Zurich, Zurich, Switzerland
    J Physiol 588:3397-402. 2010
    ..Notably, in a subset of cells we resolved Ca(2+) transients evoked by mechanical stimulation of the paw. These advances open new opportunities to study both physiology and pathology of spinal cord neural circuits in vivo...
  15. doi request reprint Miniaturized selective plane illumination microscopy for high-contrast in vivo fluorescence imaging
    Christoph J Engelbrecht
    Department of Neurophysiology, Brain Research Institute, University of Zurich, Winterthurerstrasse 190, CH 8057 Zurich, Switzerland
    Opt Lett 35:1413-5. 2010
    ..The miniSPIM may thus enable novel in vivo imaging approaches...
  16. ncbi request reprint Enhanced fluorescence signal in nonlinear microscopy through supplementary fiber-optic light collection
    Christoph J Engelbrecht
    Department of Neurophysiology, Brain Research Institute, University of Zurich, Winterthurerstrasse 190, CH 8057 Zurich, Switzerland
    Opt Express 17:6421-35. 2009
    ..Moreover, SUFICS reduced noise levels in calcium imaging experiments by about 23%. We recommend SUFICS as a generally applicable, effective add-on to nonlinear microscopes for enhancing fluorescence signals...
  17. pmc Online correction of licking-induced brain motion during two-photon imaging with a tunable lens
    Jerry L Chen
    J L Chen University of Zurich, Brain Research Institute, Winterthurerstrasse 190, 55H64, Zurich, CH 8057, Switzerland
    J Physiol 591:4689-98. 2013
    ..Focus correction with a tunable lens is a simple and effective method to improve the ability to monitor neuronal activity during reward-based behaviour...
  18. pmc Chronic imaging of cortical sensory map dynamics using a genetically encoded calcium indicator
    Matthias Minderer
    Brain Research Institute, Department of Neurophysiology, University of Zurich, Switzerland
    J Physiol 590:99-107. 2012
    ..This method opens new possibilities for the longitudinal study of stability and plasticity of cortical sensory representations...
  19. pmc Enhancement of CA3 hippocampal network activity by activation of group II metabotropic glutamate receptors
    Jeanne Ster
    Brain Research Institute, University of Zurich, CH 8057 Zurich, Switzerland
    Proc Natl Acad Sci U S A 108:9993-7. 2011
    ..Thus, our data indicate that hippocampal responses are modulated not only by presynaptic mGluRIIs that reduce glutamate release but also by postsynaptic mGluRIIs that depolarize neurons and enhance CA3 network activity...
  20. doi request reprint Optical probing of neuronal ensemble activity
    Benjamin F Grewe
    Department of Neurophysiology, Brain Research Institute, University of Zurich, Winterthurerstrasse 190, CH 8057 Zurich, Switzerland
    Curr Opin Neurobiol 19:520-9. 2009
    ..Optical probing of neuronal ensemble dynamics in vivo thus promises to reveal fundamental principles of neural circuit function and dysfunction...
  21. doi request reprint Steady or changing? Long-term monitoring of neuronal population activity
    Henry Lütcke
    Brain Research Institute, University of Zurich, Zurich, Switzerland
    Trends Neurosci 36:375-84. 2013
    ..Tuning properties appear more flexible and may be adaptively stabilized, possibly by neuromodulators, to encode reliably and specifically salient stimuli or behaviors. ..
  22. pmc Selective regulation of NR2B by protein phosphatase-1 for the control of the NMDA receptor in neuroprotection
    Mélissa Farinelli
    Brain Research Institute, University of Zurich, Zurich, Switzerland
    PLoS ONE 7:e34047. 2012
    ..They provide a new target for the development of potential therapeutic treatment of neurodegeneration...
  23. doi request reprint Chapter 10. In vivo measurements of blood flow and glial cell function with two-photon laser-scanning microscopy
    Fritjof Helmchen
    Department of Neurophysiology, Brain Research Institute, University of Zurich, Zurich, Switzerland
    Methods Enzymol 444:231-54. 2008
    ..Further, we show how extensions of ultra-fast laser techniques lead to new models of stroke, where individual vessels may be targeted for occlusion with micrometer precision...
  24. pmc Representation of visual scenes by local neuronal populations in layer 2/3 of mouse visual cortex
    Björn M Kampa
    Brain Research Institute, Department of Neurophysiology, University of Zurich Zurich, Switzerland
    Front Neural Circuits 5:18. 2011
    ..Our results suggest a population code in layer 2/3 of visual cortex, where the visual environment is dynamically represented in the activation of distinct functional sub-networks...
  25. ncbi request reprint Ultra-compact fiber-optic two-photon microscope for functional fluorescence imaging in vivo
    Christoph J Engelbrecht
    Dept of Neurophysiology, Brain Research Institute, University of Zurich, Winterthurerstrasse 190, CH 8057 Zurich, Switzerland
    Opt Express 16:5556-64. 2008
    ..The microscope will be easily portable by a rat or mouse and thus should enable functional imaging in freely behaving animals...
  26. pmc Inference of neuronal network spike dynamics and topology from calcium imaging data
    Henry Lütcke
    Laboratory of Neural Circuit Dynamics, Brain Research Institute, University of Zurich Zurich, Switzerland
    Front Neural Circuits 7:201. 2013
    ..Our findings provide a benchmark for future calcium imaging studies that aim to reliably infer neuronal network properties. ..
  27. ncbi request reprint Imaging cellular network dynamics in three dimensions using fast 3D laser scanning
    Werner Göbel
    Department of Neurophysiology, Brain Research Institute, University of Zurich, Winterthurerstr 190, CH 8057 Zurich, Switzerland
    Nat Methods 4:73-9. 2007
    ..Two-photon population imaging using 3D scanning opens the field for comprehensive studies of local network dynamics in intact tissue...
  28. ncbi request reprint Calcium indicator loading of neurons using single-cell electroporation
    Thomas Nevian
    Abteilung Zellphysiologie, Max Planck Institut fur medizinische Forschung, Jahnstrasse 29, 69120 Heidelberg, Germany
    Pflugers Arch 454:675-88. 2007
    ....
  29. ncbi request reprint In vivo calcium imaging of circuit activity in cerebellar cortex
    Megan R Sullivan
    Department of Molecular Biology, Princeton University, Princeton, New Jersey, Princeton, NJ 08544, USA
    J Neurophysiol 94:1636-44. 2005
    ..Two-photon calcium imaging of bulk-loaded cerebellar cortex is thus well suited to optically monitor synaptic processing in the intact cerebellum...
  30. ncbi request reprint Sulforhodamine 101 as a specific marker of astroglia in the neocortex in vivo
    Axel Nimmerjahn
    Abteilung Zellphysiologie, Max Planck Institut fur medizinische Forschung, Jahnstr 29, 69120 Heidelberg, Germany
    Nat Methods 1:31-7. 2004
    ..We expect SR101 staining to become a principal tool for investigating astroglia in vivo...
  31. ncbi request reprint Ca2+ imaging in the mammalian brain in vivo
    Fritjof Helmchen
    Abteilung Zellphysiologie, Max Planck Insitut für medizinische Forschung, Jahnstr 29, 69120 Heidelberg, Germany
    Eur J Pharmacol 447:119-29. 2002
    ....
  32. ncbi request reprint Background synaptic activity is sparse in neocortex
    Jack Waters
    Abteilung Zellphysiologie, Max Planck Institut fur medizinische Forschung, 69120 Heidelberg, Germany
    J Neurosci 26:8267-77. 2006
    ..These conditions enhance the effectiveness of each synapse at depolarized potentials. Hence, neocortical networks are relatively quiet at rest, and the effect of synaptic background is weaker than previously thought...
  33. ncbi request reprint Raising the speed limit--fast Ca(2+) handling in dendritic spines
    Fritjof Helmchen
    Abteilung Zellphysiologie, Max Planck Institute für medizinische Forschung, Jahnstr 29, 69120 Heidelberg, Germany
    Trends Neurosci 25:438-41; discussion 441. 2002
    ..In addition structural factors, such as shape and dendritic location, could contribute to fine-tuning of spine Ca2+ handling and synaptic modification...
  34. ncbi request reprint Supralinear Ca2+ influx into dendritic tufts of layer 2/3 neocortical pyramidal neurons in vitro and in vivo
    Jack Waters
    Abteilung Zellphysiologie, Max Planck Institut fur medizinische Forschung, 69120 Heidelberg, Germany
    J Neurosci 23:8558-67. 2003
    ..This dendritic supralinearity enables layer 2/3 neurons to integrate ascending sensory input from layer 4 and associative input to layer 1...
  35. ncbi request reprint Sindbis vector SINrep(nsP2S726): a tool for rapid heterologous expression with attenuated cytotoxicity in neurons
    Jinhyun Kim
    Max Planck Institute for Medical Research, Department of Molecular Neurobiology, Jahnstrasse 29, 69120 Heidelberg, Germany
    J Neurosci Methods 133:81-90. 2004
    ..As an experimental example, we demonstrate the applicability of this system for high-resolution two-photon imaging of dendritic spines in vivo...
  36. ncbi request reprint Nonlinear anisotropic diffusion filtering of three-dimensional image data from two-photon microscopy
    Philip J Broser
    Max Planck Institut fur medizinische Forschung, Abteilung Zellphysiologie, Jahnstr 29, D 69120, Heidelberg, Germany
    J Biomed Opt 9:1253-64. 2004
    ..The filter is a valuable general tool for smoothing cellular processes and is well suited for preparing data for subsequent image segmentation and neuron reconstruction...
  37. ncbi request reprint Novel approaches to monitor and manipulate single neurons in vivo
    Michael Brecht
    Department of Neuroscience, Erasmus Medical Center, University Medical Center Rotterdam, 3015 DR Rotterdam, The Netherlands
    J Neurosci 24:9223-7. 2004
  38. ncbi request reprint Miniaturized two-photon microscope based on a flexible coherent fiber bundle and a gradient-index lens objective
    Werner Göbel
    Max Planck Institut fur medizinische Forschung, Jahnstrasse 29, 69120 Heidelberg, Germany
    Opt Lett 29:2521-3. 2004
    ..Micrometer-sized fluorescent beads and pollen grains were readily resolved. In addition, fluorescently labeled blood vessels were imaged through the fiber bundle in rat brain in vivo...
  39. pmc Imaging input and output of neocortical networks in vivo
    Jason N D Kerr
    Department of Cell Physiology, Max Planck Institute for Medical Research, Jahnstrasse 29, D 69120 Heidelberg, Germany
    Proc Natl Acad Sci U S A 102:14063-8. 2005
    ..The dissection of the various signal components in bulk-loaded tissue as demonstrated here will enable further studies of signal flow through cortical networks...
  40. pmc Lentivirus-based genetic manipulations of cortical neurons and their optical and electrophysiological monitoring in vivo
    Tanjew Dittgen
    Department of Molecular Neurobiology, Max Planck Institute for Medical Research, Jahnstrasse 29, 69120 Heidelberg, Germany
    Proc Natl Acad Sci U S A 101:18206-11. 2004
    ..This approach is ideally suited for analysis of gene functions in individual neurons in the intact brain...
  41. ncbi request reprint Spatial organization of neuronal population responses in layer 2/3 of rat barrel cortex
    Jason N D Kerr
    Department of Cell Physiology, Max Planck Institute for Medical Research, D 69120 Heidelberg, Germany
    J Neurosci 27:13316-28. 2007
    ..We conclude that, despite their sparseness and variability, L2/3 population responses show a clear spatial organization on the columnar scale...
  42. ncbi request reprint Dendritic spikes in apical dendrites of neocortical layer 2/3 pyramidal neurons
    Matthew Evan Larkum
    Abteilung Zellphysiologie, Max Planck Institut fur medizinische Forschung, D 69120 Heidelberg, Germany
    J Neurosci 27:8999-9008. 2007
    ..We conclude that L2/3 pyramidal neurons can generate dendritic spikes, sharing with L5 pyramidal neurons fundamental properties of dendritic excitability and control by inhibition...
  43. ncbi request reprint Boosting of action potential backpropagation by neocortical network activity in vivo
    Jack Waters
    Abteilung Zellphysiologie, Max Planck Institut fur medizinische Forschung, 69120 Heidelberg, Germany
    J Neurosci 24:11127-36. 2004
    ..Hence, somatic feedback to the dendrites becomes stronger with increasing network activity...