Neef, Andreas

[["dc.bibliographiccitation.firstpage","7587"],["dc.bibliographiccitation.issue","22"],["dc.bibliographiccitation.journal","The Journal of neuroscience"],["dc.bibliographiccitation.lastpage","7597"],["dc.bibliographiccitation.volume","30"],["dc.contributor.author","Buran, Bradley N."],["dc.contributor.author","Strenzke, Nicola"],["dc.contributor.author","Neef, Andreas"],["dc.contributor.author","Gundelfinger, Eckart D."],["dc.contributor.author","Moser, Tobias"],["dc.contributor.author","Liberman, M. Charles"],["dc.date.accessioned","2017-09-07T11:45:59Z"],["dc.date.available","2017-09-07T11:45:59Z"],["dc.date.issued","2010"],["dc.description.abstract","Synaptic ribbons, found at the presynaptic membrane of sensory cells in both ear and eye, have been implicated in the vesicle-pool dynamics of synaptic transmission. To elucidate ribbon function, we characterized the response properties of single auditory nerve fibers in mice lacking Bassoon, a scaffolding protein involved in anchoring ribbons to the membrane. In bassoon mutants, immunohistochemistry showed that fewer than 3% of the hair cells' afferent synapses retained anchored ribbons. Auditory nerve fibers from mutants had normal threshold, dynamic range, and postonset adaptation in response to tone bursts, and they were able to phase lock with normal precision to amplitude-modulated tones. However, spontaneous and sound-evoked discharge rates were reduced, and the reliability of spikes, particularly at stimulus onset, was significantly degraded as shown by an increased variance of first-spike latencies. Modeling based on in vitro studies of normal and mutant hair cells links these findings to reduced release rates at the synapse. The degradation of response reliability in these mutants suggests that the ribbon and/or Bassoon normally facilitate high rates of exocytosis and that its absence significantly compromises the temporal resolving power of the auditory system."],["dc.identifier.doi","10.1523/JNEUROSCI.0389-10.2010"],["dc.identifier.gro","3142908"],["dc.identifier.isi","000278288200016"],["dc.identifier.pmid","20519533"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/364"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.publisher","Soc Neuroscience"],["dc.relation.issn","0270-6474"],["dc.title","Onset Coding Is Degraded in Auditory Nerve Fibers from Mutant Mice Lacking Synaptic Ribbons"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1244"],["dc.bibliographiccitation.issue","5"],["dc.bibliographiccitation.journal","Brain Stimulation"],["dc.bibliographiccitation.lastpage","1252"],["dc.bibliographiccitation.volume","12"],["dc.contributor.author","Halawa, I."],["dc.contributor.author","Shirota, Y."],["dc.contributor.author","Neef, A."],["dc.contributor.author","Sommer, M."],["dc.contributor.author","Paulus, W."],["dc.date.accessioned","2020-12-10T14:22:48Z"],["dc.date.available","2020-12-10T14:22:48Z"],["dc.date.issued","2019"],["dc.identifier.doi","10.1016/j.brs.2019.04.012"],["dc.identifier.issn","1935-861X"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/71740"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.title","Neuronal tuning: Selective targeting of neuronal populations via manipulation of pulse width and directionality"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","e0132577"],["dc.bibliographiccitation.issue","7"],["dc.bibliographiccitation.journal","PloS one"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Stern, Shani"],["dc.contributor.author","Agudelo-Toro, Andres"],["dc.contributor.author","Rotem, Assaf"],["dc.contributor.author","Moses, Elisha"],["dc.contributor.author","Neef, Andreas"],["dc.date.accessioned","2019-07-09T11:41:25Z"],["dc.date.available","2019-07-09T11:41:25Z"],["dc.date.issued","2015"],["dc.description.abstract","Excitation of neurons by an externally induced electric field is a long standing question that has recently attracted attention due to its relevance in novel clinical intervention systems for the brain. Here we use patterned quasi one-dimensional neuronal cultures from rat hippocampus, exploiting the alignment of axons along the linear patterned culture to separate the contribution of dendrites to the excitation of the neuron from that of axons. Network disconnection by channel blockers, along with rotation of the electric field direction, allows the derivation of strength-duration (SD) curves that characterize the statistical ensemble of a population of cells. SD curves with the electric field aligned either parallel or perpendicular to the axons yield the chronaxie and rheobase of axons and dendrites respectively, and these differ considerably. Dendritic chronaxie is measured to be about 1 ms, while that of axons is on the order of 0.1 ms. Axons are thus more excitable at short time scales, but at longer time scales dendrites are more easily excited. We complement these studies with experiments on fully connected cultures. An explanation for the chronaxie of dendrites is found in the numerical simulations of passive, realistically structured dendritic trees under external stimulation. The much shorter chronaxie of axons is not captured in the passive model and may be related to active processes. The lower rheobase of dendrites at longer durations can improve brain stimulation protocols, since in the brain dendrites are less specifically oriented than axonal bundles, and the requirement for precise directional stimulation may be circumvented by using longer duration fields."],["dc.identifier.doi","10.1371/journal.pone.0132577"],["dc.identifier.pmid","26186201"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/12025"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/58422"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1932-6203"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.title","Chronaxie Measurements in Patterned Neuronal Cultures from Rat Hippocampus."],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.journal","Biophysical Journal"],["dc.contributor.author","Neef, Andreas"],["dc.contributor.author","Heinemann, Christian"],["dc.contributor.author","Moser, Tobias"],["dc.date.accessioned","2018-11-07T11:06:06Z"],["dc.date.available","2018-11-07T11:06:06Z"],["dc.date.issued","2007"],["dc.format.extent","465A"],["dc.identifier.isi","000243972403022"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/52227"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Biophysical Society"],["dc.publisher.place","Bethesda"],["dc.relation.conference","51st Annual Meeting of the Biophysical-Society"],["dc.relation.eventlocation","Baltimore, MD"],["dc.relation.issn","0006-3495"],["dc.title","High resolution on-cell capacitance measurements with a software lock-in system"],["dc.type","conference_abstract"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","e2114549118"],["dc.bibliographiccitation.issue","51"],["dc.bibliographiccitation.journal","Proceedings of the National Academy of Sciences"],["dc.bibliographiccitation.volume","118"],["dc.contributor.author","Merino, Ricardo Martins"],["dc.contributor.author","Leon-Pinzon, Carolina"],["dc.contributor.author","Stühmer, Walter"],["dc.contributor.author","Möck, Martin"],["dc.contributor.author","Staiger, Jochen F."],["dc.contributor.author","Wolf, Fred"],["dc.contributor.author","Neef, Andreas"],["dc.date.accessioned","2022-02-01T10:31:17Z"],["dc.date.available","2022-02-01T10:31:17Z"],["dc.date.issued","2021"],["dc.description.abstract","Fast oscillations in cortical circuits critically depend on GABAergic interneurons. Which interneuron types and populations can drive different cortical rhythms, however, remains unresolved and may depend on brain state. Here, we measured the sensitivity of different GABAergic interneurons in prefrontal cortex under conditions mimicking distinct brain states. While fast-spiking neurons always exhibited a wide bandwidth of around 400 Hz, the response properties of spike-frequency adapting interneurons switched with the background input\\’s statistics. Slowly fluctuating background activity, as typical for sleep or quiet wakefulness, dramatically boosted the neurons\\’ sensitivity to gamma and ripple frequencies. We developed a time-resolved dynamic gain analysis and revealed rapid sensitivity modulations that enable neurons to periodically boost gamma oscillations and ripples during specific phases of ongoing low-frequency oscillations. This mechanism predicts these prefrontal interneurons to be exquisitely sensitive to high-frequency ripples, especially during brain states characterized by slow rhythms, and to contribute substantially to theta-gamma cross-frequency coupling."],["dc.description.abstract","Fast oscillations in cortical circuits critically depend on GABAergic interneurons. Which interneuron types and populations can drive different cortical rhythms, however, remains unresolved and may depend on brain state. Here, we measured the sensitivity of different GABAergic interneurons in prefrontal cortex under conditions mimicking distinct brain states. While fast-spiking neurons always exhibited a wide bandwidth of around 400 Hz, the response properties of spike-frequency adapting interneurons switched with the background input’s statistics. Slowly fluctuating background activity, as typical for sleep or quiet wakefulness, dramatically boosted the neurons’ sensitivity to gamma and ripple frequencies. We developed a time-resolved dynamic gain analysis and revealed rapid sensitivity modulations that enable neurons to periodically boost gamma oscillations and ripples during specific phases of ongoing low-frequency oscillations. This mechanism predicts these prefrontal interneurons to be exquisitely sensitive to high-frequency ripples, especially during brain states characterized by slow rhythms, and to contribute substantially to theta-gamma cross-frequency coupling."],["dc.identifier.doi","10.1073/pnas.2114549118"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/98819"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-517"],["dc.relation.eissn","1091-6490"],["dc.relation.issn","0027-8424"],["dc.rights.uri","https://www.pnas.org/site/aboutpnas/licenses.xhtml"],["dc.title","Theta activity paradoxically boosts gamma and ripple frequency sensitivity in prefrontal interneurons"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","12933"],["dc.bibliographiccitation.issue","47"],["dc.bibliographiccitation.journal","The Journal of neuroscience"],["dc.bibliographiccitation.lastpage","12944"],["dc.bibliographiccitation.volume","27"],["dc.contributor.author","Neef, Andreas"],["dc.contributor.author","Khimich, Darina"],["dc.contributor.author","Pirih, Primoz"],["dc.contributor.author","Riedel, Dietmar"],["dc.contributor.author","Wolf, Fred"],["dc.contributor.author","Moser, Tobias"],["dc.date.accessioned","2017-09-07T11:49:23Z"],["dc.date.available","2017-09-07T11:49:23Z"],["dc.date.issued","2007"],["dc.description.abstract","Hearing relies on faithful synaptic transmission at the ribbon synapse of cochlear inner hair cells (IHCs). Postsynaptic recordings from this synapse in prehearing animals had delivered strong indications for synchronized release of several vesicles. The underlying mechanism, however, remains unclear. Here, we used presynaptic membrane capacitance measurements to test whether IHCs release vesicles in a statistically independent or dependent ( coordinated) manner. Exocytic changes of membrane capacitance (Delta C-m) were repeatedly stimulated in IHCs of prehearing and hearing mice by short depolarizations to preferentially recruit the readily releasable pool of synaptic vesicles. A compound Poisson model was devised to describe hair cell exocytosis and to test the analysis. From the trial-to-trial fluctuations of the Delta C-m we were able to estimate the apparent size of the elementary fusion event (C-app) at the hair cell synapse to be 96-223 aF in immature and 55-149 aF in mature IHCs. We also approximated the single vesicle capacitance in IHCs by measurements of synaptic vesicle diameters in electron micrographs. The results (immature, 48 aF; mature, 45 aF) were lower than the respective Capp estimates. This indicates that coordinated exocytosis of synaptic vesicles occurs at both immature and mature hair cell synapses. Approximately 35% of the release events in mature IHCs and similar to 50% in immature IHCs were predicted to involve coordinated fusion, when assuming a geometric distribution of elementary sizes. In summary, our presynaptic measurements indicate coordinated exocytosis but argue for a lesser degree of coordination than suggested by postsynaptic recordings."],["dc.identifier.doi","10.1523/JNEUROSCI.1996-07.2007"],["dc.identifier.gro","3143408"],["dc.identifier.isi","000251157200022"],["dc.identifier.pmid","18032667"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/919"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.publisher","Soc Neuroscience"],["dc.relation.issn","0270-6474"],["dc.title","Probing the mechanism of exocytosis at the hair cell ribbon synapse"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.journal","Cardiovascular Research"],["dc.bibliographiccitation.volume","87"],["dc.contributor.author","Fluschnik, Nina"],["dc.contributor.author","Sossalla, Samuel T."],["dc.contributor.author","Ort, Katharina R."],["dc.contributor.author","Neef, S."],["dc.contributor.author","Hasenfuß, Gerd"],["dc.contributor.author","Maier, Lars. S."],["dc.date.accessioned","2018-11-07T08:41:33Z"],["dc.date.available","2018-11-07T08:41:33Z"],["dc.date.issued","2010"],["dc.format.extent","S93"],["dc.identifier.isi","000282114100226"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/19494"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Oxford Univ Press"],["dc.publisher.place","Oxford"],["dc.relation.eventlocation","Berlin, GERMANY"],["dc.relation.issn","0008-6363"],["dc.title","Beneficial effects of CaMKII inhibition in the human failing heart"],["dc.type","conference_abstract"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","BMC Neuroscience"],["dc.bibliographiccitation.lastpage","1"],["dc.bibliographiccitation.volume","14"],["dc.contributor.author","Hofmann, David"],["dc.contributor.author","Neef, Andreas"],["dc.contributor.author","Fleidervish, Ilya"],["dc.contributor.author","Gutnick, Michael"],["dc.contributor.author","Wolf, Fred"],["dc.date.accessioned","2014-07-02T10:46:49Z"],["dc.date.accessioned","2021-10-27T13:18:24Z"],["dc.date.available","2014-07-02T10:46:49Z"],["dc.date.available","2021-10-27T13:18:24Z"],["dc.date.issued","2013"],["dc.format.mimetype","application/pdf"],["dc.identifier.doi","10.1186/1471-2202-14-S1-P419"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/10421"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/91866"],["dc.language.iso","en"],["dc.notes.intern","Migrated from goescholar"],["dc.publisher","BioMed Central"],["dc.publisher.place","London"],["dc.relation.eissn","1471-2202"],["dc.relation.orgunit","Fakultät für Mathematik und Informatik"],["dc.rights","Goescholar"],["dc.rights.access","openAccess"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","How do channel densities and various time constants affect the dynamic gain of a detailed model of a pyramidal neuron?"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","335"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Pflügers Archiv European Journal of Physiology"],["dc.bibliographiccitation.lastpage","344"],["dc.bibliographiccitation.volume","454"],["dc.contributor.author","Neef, Andreas"],["dc.contributor.author","Heinemann, Christian"],["dc.contributor.author","Moser, Tobias"],["dc.date.accessioned","2017-09-07T11:49:48Z"],["dc.date.available","2017-09-07T11:49:48Z"],["dc.date.issued","2007"],["dc.description.abstract","On-cell patch-clamp capacitance measurements can resolve the fusion of individual vesicles to a membrane patch and the accompanying dilation of the fusion pore. So far, these measurements have used a patch-clamp amplifier in combination with a hardware lock-in amplifier. Usually, solely the capacitance and conductance outputs of hardware lock-in amplifiers were recorded, which needed to be filtered rather heavily to suppress spectral components at the stimulus frequency. Therefore, the temporal resolution was limited, and information carried in the patch current was not utilized. In this paper, we describe an alternative and more versatile approach for measuring patch capacitance and conductance, using a digitally controlled patch-clamp amplifier. The software lock-in system showed better bandwidth and identical signal-to-noise performance needing less instrumentation. High temporal resolution measurements on patches of chromaffin cells showed that vesicle fission can be completed in only tens of microseconds. Capacitance calculation based on the patch current allows for straightforward offline phase correction. Moreover, the close inspection of direct current for the first time revealed small current changes accompanying the fusion and fission of large secretory vesicles, promising new insights into the vesicles' membrane properties. A practical guide to high-resolution on-cell patch-clamp capacitance measurements using the software lock-in is provided."],["dc.identifier.doi","10.1007/s00424-006-0191-1"],["dc.identifier.gro","3143507"],["dc.identifier.isi","000245361500015"],["dc.identifier.pmid","17206448"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/1029"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.publisher","Springer"],["dc.relation.issn","0031-6768"],["dc.title","Measurements of membrane patch capacitance using a software-based lock-in system"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.journal","Frontiers in Neural Circuits"],["dc.bibliographiccitation.volume","7"],["dc.contributor.author","Witt, Annette"],["dc.contributor.author","Palmigiano, Agostina"],["dc.contributor.author","Neef, Andreas"],["dc.contributor.author","El Hady, Ahmed"],["dc.contributor.author","Wolf, Fred"],["dc.contributor.author","Battaglia, Demian"],["dc.date.accessioned","2017-09-07T11:45:38Z"],["dc.date.available","2017-09-07T11:45:38Z"],["dc.date.issued","2013"],["dc.description.abstract","Dynamic oscillatory coherence is believed to play a central role in flexible communication between brain circuits. To test this communication-through-coherence hypothesis, experimental protocols that allow a reliable control of phase-relations between neuronal populations are needed. In this modeling study, we explore the potential of closed-loop optogenetic stimulation for the control of functional interactions mediated by oscillatory coherence. The theory of non-linear oscillators predicts that the efficacy of local stimulation will depend not only on the stimulation intensity but also on its timing relative to the ongoing oscillation in the target area. Induced phase-shifts are expected to be stronger when the stimulation is applied within specific narrow phase intervals. Conversely, stimulations with the same or even stronger intensity are less effective when timed randomly. Stimulation should thus be properly phased with respect to ongoing oscillations (in order to optimally perturb them) and the timing of the stimulation onset must be determined by a real-time phase analysis of simultaneously recorded local field potentials (LFPs). Here, we introduce an electrophysiologically calibrated model of Channelrhodopsin 2 (ChR2)-induced photocurrents, based on fits holding over two decades of light intensity. Through simulations of a neural population which undergoes coherent gamma oscillations—either spontaneously or as an effect of continuous optogenetic driving—we show that precisely-timed photostimulation pulses can be used to shift the phase of oscillation, even at transduction rates smaller than 25%. We consider then a canonic circuit with two inter-connected neural populations oscillating with gamma frequency in a phase-locked manner. We demonstrate that photostimulation pulses applied locally to a single population can induce, if precisely phased, a lasting reorganization of the phase-locking pattern and hence modify functional interactions between the two populations."],["dc.identifier.doi","10.3389/fncir.2013.00049"],["dc.identifier.fs","599401"],["dc.identifier.gro","3151827"],["dc.identifier.pmid","23616748"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/10678"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/8657"],["dc.language.iso","en"],["dc.notes","Financial support by the German Federal Ministry of Education and Research (BMBF) via the Bernstein Center for Computational Neuroscience—Göttingen (01GQ1005B, 01GQ0430, 01GQ07113), the Bernstein Focus Neurotechnology—Göttingen (01GQ0811) and the Bernstein Focus Visual Learning (01GQ0921, 01GQ0922), the German Israel Research Foundation and the VolkswagenStiftung (ZN2632) and the Deutsche Forschungsgemeinschaft through CRC-889 (906-17.1/2006)."],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","public"],["dc.notes.submitter","chake"],["dc.relation.issn","1662-5110"],["dc.relation.orgunit","Fakultät für Physik"],["dc.subject.mesh","Action Potentials"],["dc.subject.mesh","Biological Clocks"],["dc.subject.mesh","Computational Biology"],["dc.subject.mesh","HEK293 Cells"],["dc.subject.mesh","Humans"],["dc.subject.mesh","Neural Networks (Computer)"],["dc.subject.mesh","Optogenetics"],["dc.subject.mesh","Photic Stimulation"],["dc.subject.mesh","Random Allocation"],["dc.subject.mesh","Time Factors"],["dc.title","Controlling the oscillation phase through precisely timed closed-loop optogenetic stimulation: a computational study"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","no"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]