A5091335734- Neural dynamics and brain function
- Neuroscience and Neuropharmacology Research
- Neuroscience and Neural Engineering
- Photoreceptor and optogenetics research
- Advanced Fluorescence Microscopy Techniques
- Retinal Development and Disorders
- Receptor Mechanisms and Signaling
- Zebrafish Biomedical Research Applications
- Advanced Memory and Neural Computing
- Glaucoma and retinal disorders
- Cell Image Analysis Techniques
- Robotic Locomotion and Control
- Visual perception and processing mechanisms
- Bat Biology and Ecology Studies
- Neurobiology and Insect Physiology Research
- Neurotransmitter Receptor Influence on Behavior
- Memory and Neural Mechanisms
- Optical Coherence Tomography Applications
- Monoclonal and Polyclonal Antibodies Research
- Electrical Fault Detection and Protection
- Historical and Cultural Archaeology Studies
- Veterinary Pharmacology and Anesthesia
- Photovoltaic Systems and Sustainability
- Animal Vocal Communication and Behavior
- Physiological and biochemical adaptations
Tharawal Aboriginal
2022
Center of Advanced European Studies and Research
2015-2022
Brain (Germany)
2016-2022
Max Planck Institute for Neurobiology of Behavior – caesar
2022
Max Planck Institute of Animal Behavior
2022
Max Planck Society
2004-2015
Max Planck Institute for Biological Cybernetics
2008-2015
Max Planck Institute for Medical Research
2004-2013
University of California, Los Angeles
2013
Bernstein Center for Computational Neuroscience Tübingen
2013
Neural activity manifests itself as complex spatiotemporal activation patterns in cell populations. Even for local neural circuits, a comprehensive description of network has been impossible so far. Here we demonstrate that two-photon calcium imaging bulk-labeled tissue permits dissection input and output activities rat neocortex vivo. Besides astroglial neuronal transients, found spontaneous signals the neuropil were tightly correlated to electrocorticogram. This optical encephalogram (OEG)...
Single action potentials (APs) backpropagate into the higher-order dendrites of striatal spiny projection neurons during cortically driven “up” states. The timing these backpropagating APs relative to arriving corticostriatal excitatory inputs determines changes in dendritic calcium concentration. question arises whether this spike-timing cortical can also induce synaptic plasticity at synapses. Here we show that single postsynaptic evoked EPSP both direction and strength neurons. occurring...
Although physiological data on microcircuits involving a few inhibitory neurons in the mammalian cerebral cortex are available, quantitative relation between inhibition and excitation cortical circuits thousands of largely missing. Because distribution is very inhomogeneous cortex, it critical to map all given volume rather than rely sparse sampling methods. Here, we report comprehensive mapping interneurons (INs) columns rat somatosensory immunolabeled for neuron-specific nuclear protein...
Dopamine and glutamate are key neurotransmitters involved in learning memory mechanisms of the brain. These two neurotransmitter systems converge on nerve cells neostriatum. modulation activity-dependent plasticity at glutamatergic corticostriatal synapses has been proposed as a cellular mechanism for The present research investigated role specific subtypes dopamine receptors long-term potentiation (LTP) pathway, using intracellular recording from striatal neurons slice preparation. In...
Individual pyramidal neurons of neocortex show sparse and variable responses to sensory stimuli in vivo . It has remained unclear how this variability extends population on a trial-to-trial basis. Here, we characterized single-neuron whisker stimulation layer 2/3 (L2/3) identified columns rat barrel cortex using two-photon calcium imaging. Optical detection single action potentials from evoked transients revealed low spontaneous firing rates (0.25 Hz), response probabilities (range, 0–0.5;...
We present a miniature, flexible two-photon microscope consisting of fused coherent optical fiber bundle with 30,000 cores and gradient-index lens objective. The laser focus standard laser-scanning was scanned over the entrance surface bundle, resulting in sequential coupling into individual cores. Fluorescent light detected through bundle. Micrometer-sized fluorescent beads pollen grains were readily resolved. In addition, fluorescently labeled blood vessels imaged rat brain vivo.
Spike timing dependent plasticity (STDP) is a temporally specific extension of Hebbian associative that has tied together the presynaptic inputs relative to postsynaptic single spike. However, it difficult translate this mechanism in vivo conditions where there an abundance activity constantly impinging upon dendritic tree as well ongoing spiking backpropagates along dendrite. Theoretical studies have proposed that, addition pre- and activity, "third factor" would enable association outputs....
We describe a miniaturized head-mounted multiphoton microscope and its use for recording Ca(2+) transients from the somata of layer 2/3 neurons in visual cortex awake, freely moving rats. Images contained up to 20 were stable enough record continuously >5 min per trial trials imaging session, even as animal was running at velocities 0.6 m/s. Neuronal readily detected, responses various static stimuli observed during free movement on track. activity sparse increased when swept gaze across...
Abstract Advances in head-mounted microscopes have enabled imaging of neuronal activity using genetic tools freely moving mice but these are restricted to recording minimally lit arenas and upper cortical layers. Here we built a 2-g, three-photon excitation-based microscope, containing z -drive that access all layers while behaved fully environment. The microscope had on-board photon detectors, robust environmental light, the arena lighting was timed end each line-scan, enabling functional...
Highlights•Saccades during target pursuit align area centralis with intended direction of travel•Saccades simultaneously also retinal pattern optic flow•Post-saccade eye and head rotation reduce image blur limit information loss•Tree shrews, mice, rats have the same coordinated kineticsSummaryDuring prey pursuit, how rotations, such as saccades, enable continuous tracking erratically moving targets while enabling an animal to navigate through environment is unknown. To better understand...
This article describes the development and application of miniaturized two-photon-excited fluorescence microscopes ("two-photon fiberscopes"). Two-photon fiberscopes have been developed with aim enabling high-resolution imaging neural activity in freely behaving animals. They use fiber optics to deliver laser light for two-photon excitation. Their small front piece typically contains a miniature scanning mechanism optics. can be made sufficiently lightweight carried by rats mice allow...
Mice have a large visual field that is constantly stabilized by vestibular ocular reflex (VOR) driven eye rotations counter head-rotations. While maintaining their extensive coverage advantageous for predator detection, mice also track and capture prey using vision. However, in the freely moving animal quantifying object location of view challenging. Here, we developed method to digitally reconstruct quantify scene performing visually based task. By isolating sense combining mouse optic...
Striatal spiny projection neurons control basal ganglia outputs via action potential bursts conveyed to the globus pallidus and substantia nigra. Accordingly, burst activity in these contributes importantly function dysfunction. These are driven by multiple corticostriatal inputs that depolarize from their resting of approximately −85 mV, which is down-state, a subthreshold up-state −55 mV. To understand dendritic processing during up-states, changes intracellular calcium concentration...
Up-states represent a key feature of synaptic integration in cortex and striatum that involves activation many inputs. In the striatum, sparse firing tight control action potential timing is contrast to large intracellular membrane depolarizations observed during up-state. One hallmark striatal spiny projection neurons delay generation both up-states suprathreshold depolarization by somatic current injection. By studying dendritic calcium ([Ca 2+ ] i ) transients spontaneous...
Sensory signals are transmitted via the thalamus primarily to layer 4 (L4) of primary sensory cortices. While information about average neuronal connectivity in L4 is available, its detailed higher-order circuit structure not known. Here, we used three-dimensional electron microscopy for a connectomic analysis thalamus-driven inhibitory network L4. We find that thalamic input drives subset interneurons with high specificity, which turn target excitatory neurons subtype specificity. These...