Conference Meetings Research Articles

Pharmacological analysis of the spatiotemporal activity pattern in the chicken optic tectum

Event Abstract Back to Event Pharmacological analysis of the spatiotemporal activity pattern in the chicken optic tectum Stefan Weigel1* and Harald Luksch1 1 Technische Universität München, Zoology, Germany The midbrain is an important processing area for sensory information in vertebrates. The optic tectum (TeO) and its mammalian counterpart, the superior colliculus, receive multimodal, topographic information and contain a sensory map which plays a role in spatial attention and in orientation movements. In avian, the TeO consists of 15 layers including separated input and output areas making it an ideal model system to study multimodal integration. Previous studies have mostly focused on characterization of particular cell types or cytochemistry. Only few studies have investigated network activation throughout the depth of the tectum. Our aim is to analyze the architecture and function of tectal local neuronal circuitry as well as the interplay between the TeO and modulatory midbrain areas e.g. the nuclei isthmi. To understand those complex interactions, we need to explore the spatiotemporal activity patterns with respect to the general cytoarchitecture of the TeO. We use an optical imaging approach with voltage sensitive dyes (RH795) to investigate population responses at a high temporal and spatial resolution in a chicken midbrain slice preparation. Thus, we can match activity patterns to the general layout of the TeO based on histological data. Based on histological data we can roughly link our findings with the general layout of the avian TeO. Here, we show inter- and intralaminar neuronal activities under different pharmacological regimes. The TeO section was activated by electrical stimulation of afferent layers, which mimicked the input from retinal ganglion cells. This evoked a two-component neuronal response consisting of a short (~10 ms) and a long-lasting component (up to several hundred ms) extending (i) in layer 5, where horizontally aligned neurons are located, and (ii) into deeper layers along radial oriented neurons. Ca2+-free solution and AMPA receptor restricted activity to the site of stimulation, indicating that most of the signal was postsynaptic and glutamatergic. Disinhibition enhanced signal amplitudes and spatial extent of the excitation. Interestingly, cholinergic transmitters were important in retention of the inhibition in the slice preparation indicating complex local networks. We will propose a simple model for the circuitry in the TeO. Keywords: avian, brain slice, midbrain, multimodal, optic tectum, visual, voltage sensitive dye imaging Conference: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011, Freiburg, Germany, 4 Oct - 6 Oct, 2011. Presentation Type: Poster Topic: sensory processing (please use "sensory processing" as keyword) Citation: Weigel S and Luksch H (2011). Pharmacological analysis of the spatiotemporal activity pattern in the chicken optic tectum. Front. Comput. Neurosci. Conference Abstract: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011. doi: 10.3389/conf.fncom.2011.53.00136 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 23 Aug 2011; Published Online: 04 Oct 2011. * Correspondence: Dr. Stefan Weigel, Technische Universität München, Zoology, Freising, 85354, Germany, stefan.weigel@wzw.tum.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Stefan Weigel Harald Luksch Google Stefan Weigel Harald Luksch Google Scholar Stefan Weigel Harald Luksch PubMed Stefan Weigel Harald Luksch Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Extraction of functional domains in optical imaging data using regularized nonnegative matrix factorization

Event Abstract Back to Event Extraction of functional domains in optical imaging data using regularized nonnegative matrix factorization Jan Soelter1*, Jan Schumacher2, Antonia Strutz3, Silke Sachse3, Hartwig Spors2 and Michael Schmuker1, 4 1 Freie Universität Berlin, Institute of Biology, Germany 2 Max Planck Institute of Biophysics, Department of Molecular Neurogenetics, Germany 3 Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Germany 4 Bernstein Center for Computational Neuroscience Berlin, Germany Functional optical imaging is widely used to measure neuronal activity in the living brain. In many cases, the neuronal activity exhibits spatial structure which reflects a distinct physiological organization of the tissue. However, exact data on that organization is often not available in functional imaging. This poses the challenge of automatically estimating distinct spatial domains and their corresponding stimulus response based on functional data alone. The decomposition of observations into their generating sources is an instance of the Blind Source Separation problem. Previous approaches to this problem were based on Principal and Independent Component Analysis. However, both methods reach their limits if the number of sources lies within the range of the number of images, or even exceeds them. In this contribution, we introduce a regularized non-negative matrix factorization algorithm to overcome this problem. Using a toy dataset, we compare its performance to established approaches. In addition, we demonstrate its applicability in two natural datasets where the non-negativity condition is met: to discover (a) glomeruli, the functional domains of the olfactory bulb in mice, in intrinsic optical images and (b) inhibitory olfactory projection neurons in calcium imaging data of the lateral horn of Drosophila. To cope with the low observation to source ratio, we restricted the generative model in the introduced algorithm in several ways. The non-negative matrix factorization itself imposed the constraint of only positive contributions of the sources. Moreover, a sparseness constraint enforced localized sources. Additionally, we introduced a new modification in the Hierarchical Alternating Least Squares (HALS) algorithm to promote spatially decorrelated sources. Acknowledgements Funded by DFG grant no. SCHM2474/1-1 to M.S. (SPP 1392, principal source of funding), BMBF grant no. 01GQ1001D (BCCN Berlin) to M.S., BMBF grant no. 01GQ0807 to S.S., DFG grant no. SP 1134/2-1to H.S. (SPP 1392). Keywords: calcium imaging, data analysis and machine learning, Drosophila lateral horn, Intrinsic signal imaging, mouse olfactory bulb Conference: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011, Freiburg, Germany, 4 Oct - 6 Oct, 2011. Presentation Type: Poster Topic: data analysis and machine learning (please use "data analysis and machine learning" as keyword) Citation: Soelter J, Schumacher J, Strutz A, Sachse S, Spors H and Schmuker M (2011). Extraction of functional domains in optical imaging data using regularized nonnegative matrix factorization. Front. Comput. Neurosci. Conference Abstract: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011. doi: 10.3389/conf.fncom.2011.53.00077 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 23 Aug 2011; Published Online: 04 Oct 2011. * Correspondence: Mr. Jan Soelter, Freie Universität Berlin, Institute of Biology, Berlin, 14195, Germany, j.soelter@fu-berlin.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Jan Soelter Jan Schumacher Antonia Strutz Silke Sachse Hartwig Spors Michael Schmuker Google Jan Soelter Jan Schumacher Antonia Strutz Silke Sachse Hartwig Spors Michael Schmuker Google Scholar Jan Soelter Jan Schumacher Antonia Strutz Silke Sachse Hartwig Spors Michael Schmuker PubMed Jan Soelter Jan Schumacher Antonia Strutz Silke Sachse Hartwig Spors Michael Schmuker Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Representational capacity of neural codes in the cortex

Event Abstract Back to Event Representational capacity of neural codes in the cortex Mark C. Van Rossum1* 1 University of Edinburgh, Institute for Adaptive and Neural Computation, United Kingdom The coding of sensory stimuli in the neural response is a fundamental property of neural systems that impacts many of its properties. The coding scheme also determines how many different stimuli a population of neurons can represent. Although the coding of single stimuli has been studied extensively, coding of multiple stimuli has been studied far less. Here we study the representational capacity in the visual system when stimulus pairs are represented simultaneously. We assume that the response to the individual stimuli is given, and that the neurons interacts non-linearly to form the response to the pair. Using a Bayesian read-out we find that using a linear sum leads to a smaller capacity, than a maximum-like interaction. Thus non-linear interaction improve coding capacity. The results provide a novel interpretation for the non-linear interaction observed experimentally. Keywords: Plasticity and Learning Conference: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011, Freiburg, Germany, 4 Oct - 6 Oct, 2011. Presentation Type: Keynote Topic: other Citation: Van Rossum MC (2011). Representational capacity of neural codes in the cortex. Front. Comput. Neurosci. Conference Abstract: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011. doi: 10.3389/conf.fncom.2011.53.00007 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 26 Sep 2011; Published Online: 04 Oct 2011. * Correspondence: Dr. Mark C Van Rossum, University of Edinburgh, Institute for Adaptive and Neural Computation, Edinburgh, United Kingdom, mark.vanrossum@nottingham.ac.uk Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Mark C Van Rossum Google Mark C Van Rossum Google Scholar Mark C Van Rossum PubMed Mark C Van Rossum Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Progress toward a high-performance brain-controlled interface

Event Abstract Back to Event Progress toward a high-performance brain-controlled interface Andrew Schwartz1* 1 University of Pittsburgh, Motorlab, United States A better understanding neural population function would be an important advance in systems neuroscience. The change in emphasis from the single neuron to the neural ensemble has made it possible to extract high-fidelity information about movements that will occur in the near future. This ability is due to the distributed nature of information processing in the brain. Neurons encode many parameters simultaneously, but the fidelity of encoding at the level of individual neurons is weak. However, because encoding is redundant and consistent across the population, extraction methods based on multiple neurons are capable of generating a faithful representation of intended movement. The realization that useful information is embedded in the population has spawned the current success of brain-controlled interfaces. Since multiple movement parameters are encoded simultaneously in the same population of neurons, we have been gradually increasing the degrees of freedom (DOF) that a subject can control through the interface. Our early work showed that 3-dimensions could be controlled in a virtual reality task. We then demonstrated control of an anthropomorphic physical device with 4 DOF in a self-feeding task. Currently, monkeys in our laboratory are using this interface to control a 7-DOF arm, wrist and hand to grasp objects in different locations and orientations. Our recent data show that we can extract 10-DOF to add hand shape and dexterity to our control set. Keywords: Motor Decoding and Brain-Machine Interfaces Conference: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011, Freiburg, Germany, 4 Oct - 6 Oct, 2011. Presentation Type: Keynote Topic: other Citation: Schwartz A (2011). Progress toward a high-performance brain-controlled interface. Front. Comput. Neurosci. Conference Abstract: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011. doi: 10.3389/conf.fncom.2011.53.00004 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 26 Sep 2011; Published Online: 04 Oct 2011. * Correspondence: Prof. Andrew Schwartz, University of Pittsburgh, Motorlab, Pittsburgh, United States, abs21@pitt.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Andrew Schwartz Google Andrew Schwartz Google Scholar Andrew Schwartz PubMed Andrew Schwartz Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Morphological and Molecular Characterization of Focal Cortical Dysplasias

Event Abstract Back to Event Morphological and Molecular Characterization of Focal Cortical Dysplasias Catharina Donkels1*, Susanne Fauser2, Dietmar Pfeifer3, Josef Zentner4 and Carola A. Haas5 1 University of Freiburg, Experimental Epilepsy Research, Germany 2 University of Freiburg, Epilepsy Center, Germany 3 University of Freiburg, Department of Hematology & Oncology, Germany 4 University of Freiburg, Department of Neurosurgery, Germany 5 University of Freiburg, Experimental Epilepsy Research, Germany Focal cortical dysplasias (FCD) are malformations of the human neocortex which are highly associated with intractable epilepsy, especially in young children. The neuropathological characteristics of FCD extend from mild laminar disorganization and hypertrophic neurons (FCD type I) to severely developed laminar disorders with the appearance of dysmorphic neurons and cytomegalic cells (FCD type II) (Palmini et al. 2004). It is assumed that FCD arise due to local disturbances during prenatal development. To date very little is known about structural and molecular composition of these cortical malformations and to which extent they differ from normally developed neocortex. To address this question we used a combined morphological and molecular approach to analyze human resected FCD (type I and II) specimens from different cortical areas, obtained from patients with pharmaco-resistant epilepsy. In each FCD sample the degree of dyslamination was visualized by immunolabeling for NeuN and non-phosphorylated neurofilament H (SMI32), a marker for pyramidal cell layers 3 and 5, and, in parallel, the expression of genes encoding markers of laminar fate (e.g. reelin, Er81, Rorß, TLE4) , interneurons and cell maturity (e.g. doublecortin) was analyzed by real time RT-PCR. In addition we performed expression microarray analysis from FCD IB type temporal lobe neocortex. We found that in all specimens lamination was basically preserved, but there were strong differences with respect to lamina width, in some cases layers were even blurred. In addition, RT-PCR analysis revealed that laminar fate and interneuron markers were basically expressed, but with high variability mirroring the morphological observations. Our expression array results show low effect sizes concerning expression level differences in FCD specimens in comparison to control tumor access tissue due to the heterogeneous FCD tissue type. Furthermore we also could confirm our PCR and morphological results regarding to various expression levels for single gene/markers even among the FCD and especially the control group. Taken together, our data indicate that FCD show not a homogenous disease pattern but a much more complex one than initially assumed. Acknowledgements Supported by the Deutsche Forschungsgemeinschaft (DFG FA 775/2-1) References Palmini A, Naijm I, Avanzini G, Babb T, Guerrini R, Foldvary-Schaefer N, Jackson G, Lüders HO, Prayson R, Spreafico R, Vinters HV. Terminology and classification of the cortical dysplasia. Neurology 2004; 62: S2-S8. Keywords: brain disease, Epilepsy, Gene Expression, intervention, Neocortex, network dysfunction Conference: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011, Freiburg, Germany, 4 Oct - 6 Oct, 2011. Presentation Type: Poster Topic: brain disease, network dysfunction and intervention (please use "brain disease, network dysfunction and intervention" as keyword) Citation: Donkels C, Fauser S, Pfeifer D, Zentner J and Haas CA (2011). Morphological and Molecular Characterization of Focal Cortical Dysplasias. Front. Comput. Neurosci. Conference Abstract: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011. doi: 10.3389/conf.fncom.2011.53.00178 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 22 Aug 2011; Published Online: 04 Oct 2011. * Correspondence: Ms. Catharina Donkels, University of Freiburg, Experimental Epilepsy Research, Freiburg, Germany, catharina.donkels@uniklinik-freiburg.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Catharina Donkels Susanne Fauser Dietmar Pfeifer Josef Zentner Carola A Haas Google Catharina Donkels Susanne Fauser Dietmar Pfeifer Josef Zentner Carola A Haas Google Scholar Catharina Donkels Susanne Fauser Dietmar Pfeifer Josef Zentner Carola A Haas PubMed Catharina Donkels Susanne Fauser Dietmar Pfeifer Josef Zentner Carola A Haas Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Online data analysis for a Knee-Ankle-Foot-Orthosis with neuro-control

Online data analysis for a Knee-Ankle-Foot-Orthosis with neuro-control

Parvalbumin deficiency affects burst discharges but not network properties of the RTN.

Parvalbumin deficiency affects burst discharges but not network properties of the RTN.

Computational modeling of intracellular chloride accumulation and diffusion

Event Abstract Back to Event Computational modeling of intracellular chloride accumulation and diffusion Peter Jedlicka1*, Thomas Deller1, Kurt H. Backus2 and Boris Gutkin3 1 Goethe University, Clinical Neuroanatomy, Germany 2 Goethe University, Institute of Physiology, Germany 3 Ecole Normale Supérieure, Group for Neural Theory, France It is well established that spatiotemporal dynamics of intracellular chloride affect GABAergic synaptic transmission and its reversal potential (EGABA). Our simulations of chloride diffusion within dendrites suggest that EGABA changes induced by activation of GABAergic dendritic synapses propagate beyond the site of chloride influx and affect neighbouring synapses. References Jedlicka P, Deller T, Gutkin B, Backus KH (2011) Activity-dependent intracellular chloride accumulation and diffusion controls GABAA receptor-mediated synaptic transmission. Hippocampus 21:885-898 Keywords: chloride, Depolarization, Diffusion, GABA, KCC2 Conference: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011, Freiburg, Germany, 4 Oct - 6 Oct, 2011. Presentation Type: Poster Topic: other Citation: Jedlicka P, Deller T, Backus KH and Gutkin B (2011). Computational modeling of intracellular chloride accumulation and diffusion. Front. Comput. Neurosci. Conference Abstract: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011. doi: 10.3389/conf.fncom.2011.53.00121 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 23 Aug 2011; Published Online: 04 Oct 2011. * Correspondence: Dr. Peter Jedlicka, Goethe University, Clinical Neuroanatomy, Frankfurt, Germany, peterjedlicka@yahoo.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Peter Jedlicka Thomas Deller Kurt H Backus Boris Gutkin Google Peter Jedlicka Thomas Deller Kurt H Backus Boris Gutkin Google Scholar Peter Jedlicka Thomas Deller Kurt H Backus Boris Gutkin PubMed Peter Jedlicka Thomas Deller Kurt H Backus Boris Gutkin Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Edge and image statistics across the visual field

Event Abstract Back to Event Edge and image statistics across the visual field Daniela Pamplona1*, Jochen Triesch1 and Constantin A. Rothkopf1 1 Frankfurt Institute for Advanced Studies, Germany The efficient coding hypothesis posits that sensory systems take the statistical regularities present in the environment into account in order to reduce redundancies in their representation. Spatial correlations in natural images have been considered repeatedly and are commonly characterized through their power spectrum, which has empirically been shown to fall approximately according to 1/f2, where f is the spatial frequency. This has led several studies to propose explaining the properties of retinal ganglion cells and the psychophysically measured contrast sensitivity function in terms of these regularities. Similarly, psychophysical performance in a variety of contour perception tasks has been related to the distribution of edge elements in natural scenes. But usually the power spectrum and the distribution of edge elements are treated as invariant across the visual field. Additionally the spectrum is reduced to a one-dimensional function of spatial frequency by rotationally averaging the two-dimensional spectrum assuming rotational invariance. Furthermore, the power spectra underlying such analysis are commonly obtained as averages over large sets of images. To reduce the redundancy, for instance, under the assumption of additive white noise, it can be shown that the optimal filter is the product of a whitening filter and a lowpass filter. This Wiener filter has been applied to natural images, the resulting filters have been shown to be closely related to retinal Ganglion cells’ receptive fields. However, this method does not explain the variability of ganglion receptive fields across the visual field. We abandon the three assumptions above and show that taking into account the power spectrum variability, in terms of the orientation, position across the field of view leads to a rich set of filters, which can be succinctly captured parametrically. From the power spectra analysis, we generate a population of whitening filters. We verify that the emerged filters keep the center-surround shape, however, they do not have the usual circular concentric shape. Moreover, by explicitly modeling the geometric transforms imposed by the imaging process of the eye we furthermore estimate the distribution of edges across the visual field. This provides testable predictions of the properties of ganglion cells across the visual field. We conclude that to understand properties of sensory neurons it is important not only to consider the regularities in the natural environment but also the regularities imposed by the imaging process. Acknowledgements This work was supported by the BMBF Project "Bernstein Fokus: Neurotechnologie Frankfurt", FKZ01GQ0840 Keywords: edge statistics, field of view, image statistics Conference: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011, Freiburg, Germany, 4 Oct - 6 Oct, 2011. Presentation Type: Poster Topic: sensory processing (please use "sensory processing" as keyword) Citation: Pamplona D, Triesch J and Rothkopf CA (2011). Edge and image statistics across the visual field. Front. Comput. Neurosci. Conference Abstract: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011. doi: 10.3389/conf.fncom.2011.53.00131 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 23 Aug 2011; Published Online: 04 Oct 2011. * Correspondence: Miss. Daniela Pamplona, Frankfurt Institute for Advanced Studies, 60438, Frankfurt am Main, Germany, daniela.pamplona@inria.fr Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Daniela Pamplona Jochen Triesch Constantin A Rothkopf Google Daniela Pamplona Jochen Triesch Constantin A Rothkopf Google Scholar Daniela Pamplona Jochen Triesch Constantin A Rothkopf PubMed Daniela Pamplona Jochen Triesch Constantin A Rothkopf Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

A doubly stochastic model for the quantification and classification of burstiness and regularity in single spike trains

A doubly stochastic model for the quantification and classification of burstiness and regularity in single spike trains

Cognitive processing and functional interactions within hippocampal-neocortical networks during a spatial working memory task in humans

Cognitive processing and functional interactions within hippocampal-neocortical networks during a spatial working memory task in humans

A Model of human dichromat color vision that may help to explain the evolution of trichromacy

A Model of human dichromat color vision that may help to explain the evolution of trichromacy

Exploiting basal ganglia tricks to cure its disorders

Event Abstract Back to Event Exploiting basal ganglia tricks to cure its disorders Hagai Bergman1* 1 The Hebrew University, Hadassah Medical School Jerusalem, Israel Reinforcement learning models postulate that the basal ganglia networks are built as Actor/Critic network and employ bootstrap temporal difference algorithms to achieve optimal behavioural policy through interactions with stochastic environment and despite delayed and incomplete (scalar) feedback. Continuous high-frequency Deep Brain Stimulation (DBS) is a popular therapy for management of advanced Parkinson's disease – the most common disorder of the basal ganglia. However, since in present DBS systems stimulation parameters are only intermittently adjusted, DBS methods are poorly suited to cope with the fast neuronal and clinical dynamics of Parkinson's disease. We tested the effects of closed-loop stimulation in the MPTP primate model of Parkinson's disease. Closed-loop stimulation has a significantly greater effect on akinesia and on cortical and pallidal discharge patterns than standard open-loop DBS and matched control stimulation paradigms. Thus, closed-loop DBS paradigms have potential not only for the treatment of Parkinson's disease, but perhaps of other neurological/psychiatric disorders in which a clear pathological pattern of brain activity is recognized. Keywords: Basal Ganglia and Deep Brain Stimulation Conference: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011, Freiburg, Germany, 4 Oct - 6 Oct, 2011. Presentation Type: Keynote Topic: other Citation: Bergman H (2011). Exploiting basal ganglia tricks to cure its disorders. Front. Comput. Neurosci. Conference Abstract: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011. doi: 10.3389/conf.fncom.2011.53.00030 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 26 Sep 2011; Published Online: 04 Oct 2011. * Correspondence: Prof. Hagai Bergman, The Hebrew University, Hadassah Medical School Jerusalem, Jerusalem, Israel, hagaib@md.huji.ac.il Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Hagai Bergman Google Hagai Bergman Google Scholar Hagai Bergman PubMed Hagai Bergman Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

When less is more: Non-monotonic spike sequence processing in neurons

Event Abstract Back to Event When less is more: Non-monotonic spike sequence processing in neurons Hinrich Kielblock1, 2*, Birk Urmersbach1, Shuwen Chang3, Holger Taschenberger3 and Marc Timme1, 2 1 Max Planck Institute for Dynamics and Self-Organization, Network Dynamics Group, Germany 2 Berstein Center for Computational Neuroscience Göttingen, Germany 3 Max Planck Institute for Biophysical Chemistry, Membrane Biophysics Department, Germany The computational capabilities of neural circuits centrally rely on the input-output relations of single neurons. It is commonly accepted that neurons respond to inputs monotonically such that increasing the input implies increasing the output. Yet, most theoretical and experimental input-output studies have so far focused on continuous-time inputs, whereas most neurons communicate via exchanging electrical pulses (spikes) at discrete times. Here we show that the stationary response to regular spike sequences is typically non-monotonic such that increasing the input frequency to a neuron may decrease its output frequency. The underlying mechanism relies solely on a combination of the discrete nature of the communication by spikes and generically limited resources required for input sequence processing. As a consequence, this phenomenon universally emerges across a variety of spiking neural systems. It may support stabilizing the generation of spike sequences in neural circuits. Acknowledgements We thank D. Bibichkov and S. Schreiber for valuable discussions. Partially supported by the BMBF Germany under grant no. 01GQ1005B and by a grant from the Max Planck Society to Marc Timme. Keywords: excitability, locking, Neurons, networks and dynamical systems, spike sequence processing Conference: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011, Freiburg, Germany, 4 Oct - 6 Oct, 2011. Presentation Type: Demonstration Topic: neurons, networks and dynamical systems (please use "neurons, networks and dynamical systems" as keywords) Citation: Kielblock H, Urmersbach B, Chang S, Taschenberger H and Timme M (2011). When less is more: Non-monotonic spike sequence processing in neurons. Front. Comput. Neurosci. Conference Abstract: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011. doi: 10.3389/conf.fncom.2011.53.00163 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 22 Aug 2011; Published Online: 04 Oct 2011. * Correspondence: Mr. Hinrich Kielblock, Max Planck Institute for Dynamics and Self-Organization, Network Dynamics Group, Göttingen, Germany, hinrich@nld.ds.mpg.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Hinrich Kielblock Birk Urmersbach Shuwen Chang Holger Taschenberger Marc Timme Google Hinrich Kielblock Birk Urmersbach Shuwen Chang Holger Taschenberger Marc Timme Google Scholar Hinrich Kielblock Birk Urmersbach Shuwen Chang Holger Taschenberger Marc Timme PubMed Hinrich Kielblock Birk Urmersbach Shuwen Chang Holger Taschenberger Marc Timme Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

FMRI based Granger causality as a measure of effective connectivity in macaque visual cortex

Event Abstract Back to Event fMRI based Granger causality as a measure of effective connectivity in macaque visual cortex Vesna Vuksanovic1, 2, 3*, Mario Bartolo3, Dave Hunter3, Li Sun3 and Alex Thiele3 1 Bernstein Center for Computational Neuroscience, Humboldt-Universität zu Berlin, Philippstraße 13, 10115 Berlin, Germany, Germany 2 Institut für Theoretische Physik, Technische Universität Berlin, Germany 3 Institute of Neuroscience, Newcastle university, United Kingdom Granger causality (GC) analysis of fMRI blood oxygen level dependent (BOLD) time series has been proposed as a statistical tool to analyse directional influences between remote brain regions. Ongoing BOLD activity is treated as a set of stochastic time series (STS) generated by stochastic processes whose properties can be captured by autoregressive models. GC quantifies the improvement in predicting one brain region STS by inclusion of that from another region. Here, we show how GC can be tested using the ensemble of single-voxel time series in a region of interest (ROI). Granger causality was tested on F statistics derived from linear regression models using BOLD time series. Ongoing BOLD activity was extracted from four ROIs: three in V1 and one in MT/V5 area of the macaque visual cortex. fMRI scans were made under three stimulus conditions, whereby (1) a single (‘centre’) grating was presented, (2) the single grating was flanked by 2 additional gratings, and (3) only the flanking gratings were shown. ROIs were not spatially homogenous in their influence on each other; we found a variable number of voxel pairs with significant F statistics. GC analysis showed that the V1 ROI which represented the ‘centre’ grating was influenced by the MT/V5 ROI when centre-flanker stimuli were shown, but not by the V1 ROIs representing the flanking gratings. It thus appears that centre-flanker interactions (at distances >3 deg of visual angle) arise mainly through feedback, not through lateral intra-areal connections. Keywords: dynamical systems, effective connectivity, fMRI, networks, Neurons, Visual Cortex Conference: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011, Freiburg, Germany, 4 Oct - 6 Oct, 2011. Presentation Type: Poster Topic: neurons, networks and dynamical systems (please use "neurons, networks and dynamical systems" as keywords) Citation: Vuksanovic V, Bartolo M, Hunter D, Sun L and Thiele A (2011). fMRI based Granger causality as a measure of effective connectivity in macaque visual cortex. Front. Comput. Neurosci. Conference Abstract: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011. doi: 10.3389/conf.fncom.2011.53.00200 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 19 Aug 2011; Published Online: 04 Oct 2011. * Correspondence: Dr. Vesna Vuksanovic, Bernstein Center for Computational Neuroscience, Humboldt-Universität zu Berlin, Philippstraße 13, 10115 Berlin, Germany, Berlin, Germany, 10115, Germany, vesna.vuksanovic@bccn-berlin.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Vesna Vuksanovic Mario Bartolo Dave Hunter Li Sun Alex Thiele Google Vesna Vuksanovic Mario Bartolo Dave Hunter Li Sun Alex Thiele Google Scholar Vesna Vuksanovic Mario Bartolo Dave Hunter Li Sun Alex Thiele PubMed Vesna Vuksanovic Mario Bartolo Dave Hunter Li Sun Alex Thiele Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

The motor neuron recruitment strategy and muscle anatomical properties determine the influence of synaptic noise on the variability of motor output

The motor neuron recruitment strategy and muscle anatomical properties determine the influence of synaptic noise on the variability of motor output

A Novel Approach to the Analysis of the State of Coupled Networks of Spiking Neurons in the Presence of Noise

Event Abstract Back to Event A Novel Approach to the Analysis of the State of Coupled Networks of Spiking Neurons in the Presence of Noise Farzad Farkhooi1, 2* and Carl Van Vreeswijk3, 4 1 Freie Universität Berlin, Institute of Biology, Germany 2 BCCN-Berlin, Germany 3 René Descartes University, France 4 CNRS, France The standard approach to the analysis of the stability of networks of integrate-and-fire like neurons is to apply Fokker-Planck equation for the voltage distribution in the network with boundery conditions and re-injection. In this approach the asynchronous state is obtained by determining the equilibrium distribution and its stability by considering perturbations of this state by linearizing the perturbed system yields the eigenvalue-equation. This approach is highly successful for networks with one-variable model neurons and static synapses; however, it has proven to be difficult to extend to networks of model neurons with more than one state variable, e.g. networks with short-term plasticity in noisy conditions. To overcome these problems we present a different approach: in stead of studying the evolution of the voltage distribution we analyze the system by studying how the inter-spike interval distribution evolves. This determines evolution of the firing rate, which determines the feedback input. Thus, self-consistency gives rate in the asynchronous state and also allows us to determine the eigenvalue-equation in the perturbed system. We will first show that for networks with static synapses this yields the same eigenvalue equation as the classical Fokker- Planck approach. Finally, we will show how the analysis can easily be extended to networks more state variables, for example networks of integrate and fire neurons with short-term plasticity and some results from this case. Acknowledgements FF acknowledges Bernstein Focus: Neuronal Basis of Learning by Federal Ministry of Education and Research Grant No. 01GQ0941. Keywords: Fokker-Planck equation, network dynamics, neuronal networks, short-term plasticity Conference: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011, Freiburg, Germany, 4 Oct - 6 Oct, 2011. Presentation Type: Poster Topic: neurons, networks and dynamical systems (please use "neurons, networks and dynamical systems" as keywords) Citation: Farkhooi F and Van Vreeswijk C (2011). A Novel Approach to the Analysis of the State of Coupled Networks of Spiking Neurons in the Presence of Noise. Front. Comput. Neurosci. Conference Abstract: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011. doi: 10.3389/conf.fncom.2011.53.00061 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 23 Aug 2011; Published Online: 04 Oct 2011. * Correspondence: Dr. Farzad Farkhooi, Freie Universität Berlin, Institute of Biology, Berlin, Germany, farzad.farkhooi@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Farzad Farkhooi Carl Van Vreeswijk Google Farzad Farkhooi Carl Van Vreeswijk Google Scholar Farzad Farkhooi Carl Van Vreeswijk PubMed Farzad Farkhooi Carl Van Vreeswijk Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Mapping the functional architecture of working memory in Macaque pre-frontal cortex using movable electrode arrays

Event Abstract Back to Event Mapping the functional architecture of working memory in Macaque pre-frontal cortex using movable electrode arrays David A. Markowitz1* and Bijan Pesaran1 1 New York University, Center for Neural Science, United States Prefrontal cortex (PFC) is the hub of a distributed system that coordinates the selection, planning and execution of motor behaviors. Working memory links these operations in PFC by providing temporal continuity between prior experience and present action. Although patterns of intra- and inter-layer synaptic connectivity have been identified in PFC, the laminar organization of sensory, motor and memory-related activity within this network remains unknown. To address this problem, we used a chronically implanted microdrive with independently movable electrodes to map the depth dependence of spatially tuned local field potentials (LFP) in PFC of Rhesus macaques (Macaca mulatta) as they performed memory-guided eye movements. We show that the persistent representation of a remembered target location is limited to superficial layers of PFC. By contrast, the representation of target position during cue and saccade epochs is distributed across superficial and deep cortical layers. This indicates that superficial PFC may be specialized for the maintenance of spatial working memory. Keywords: laminar, local field potential, multielectrode array, pre-frontal cortex, working memory Conference: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011, Freiburg, Germany, 4 Oct - 6 Oct, 2011. Presentation Type: Poster Topic: neural encoding and decoding (please use "neural coding and decoding" as keyword) Citation: Markowitz DA and Pesaran B (2011). Mapping the functional architecture of working memory in Macaque pre-frontal cortex using movable electrode arrays. Front. Comput. Neurosci. Conference Abstract: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011. doi: 10.3389/conf.fncom.2011.53.00082 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 24 Aug 2011; Published Online: 04 Oct 2011. * Correspondence: Dr. David A Markowitz, New York University, Center for Neural Science, New York, New York, 10003, United States, david.markowitz@nyu.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers David A Markowitz Bijan Pesaran Google David A Markowitz Bijan Pesaran Google Scholar David A Markowitz Bijan Pesaran PubMed David A Markowitz Bijan Pesaran Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Mechanisms of generation and suppression of oscillations in the basal ganglia

Event Abstract Back to Event Mechanisms of generation and suppression of oscillations in the basal ganglia Arvind Kumar1, 2, 3*, Ad Aertsen1, 2, Stefan Rotter1, 3 and Stefano Cardanobile1, 3 1 Bernstein Center Freiburg, Germany 2 University of Freiburg, Faculty of Biology, Germany 3 University of Freiburg, Faculty of Biology, Germany Movement disorders in Parkinson's disease (PD) are commonly associated with slow oscillations and increased synchrony of neuronal activity in the basal ganglia. The neural mechanisms underlying this dynamic network dysfunction, however, are only poorly understood. Here, we show that the strength of inhibitory inputs from striatum to globus pallidus external (GPe) is a key parameter controlling oscillations in the basal ganglia. Specifically, the increase in striatal activity observed in PD is sufficient to unleash the oscillations in the basal ganglia. This finding allows us to propose a unified explanation for different phenomena: absence of oscillation in the healthy state of the basal ganglia, oscillations in dopamine-depleted state and quenching of oscillations under deep brain stimulation (DBS). These novel insights help us to better understand and optimize the function of DBS protocols. Furthermore, studying the model behavior under transient increase of activity of the striatal neurons projecting to the indirect pathway, we are able to account for both motor impairment in PD patients and for reduced response inhibition in DBS implanted patients. Acknowledgements Funded in parts by the German Federal Ministry of Education and Research (BMBF grant 01GQ0420 to the BCCN Freiburg, BMBF GW0542 Cognition, and BMBF 01GW0730 Impulse Control). Keywords: Basal Ganglia and Deep Brain Stimulation Conference: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011, Freiburg, Germany, 4 Oct - 6 Oct, 2011. Presentation Type: Keynote Topic: other Citation: Kumar A, Aertsen A, Rotter S and Cardanobile S (2011). Mechanisms of generation and suppression of oscillations in the basal ganglia. Front. Comput. Neurosci. Conference Abstract: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011. doi: 10.3389/conf.fncom.2011.53.00028 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 26 Sep 2011; Published Online: 04 Oct 2011. * Correspondence: Dr. Arvind Kumar, Bernstein Center Freiburg, Freiburg, Germany, kumar@bcf.uni-freiburg.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Arvind Kumar Ad Aertsen Stefan Rotter Stefano Cardanobile Google Arvind Kumar Ad Aertsen Stefan Rotter Stefano Cardanobile Google Scholar Arvind Kumar Ad Aertsen Stefan Rotter Stefano Cardanobile PubMed Arvind Kumar Ad Aertsen Stefan Rotter Stefano Cardanobile Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Syntax, synfire, and synaptic plasticity: Modeling the generation of structure in birdsong and neuronal networks

Event Abstract Back to Event Syntax, synfire, and synaptic plasticity: Modeling the generation of structure in birdsong and neuronal networks Abigail Morrison1, 2* 1 Bernstein Center Freiburg, Germany 2 University of Freiburg, Faculty of Biology, Germany Adult Bengalese finches generate a variable song that obeys a distinct and individual syntax. The syntax is gradually lost over a period of days after deafening and is recovered when hearing is restored. In the first part of this talk I will present a spiking neuronal network model of the song syntax generation and its loss, based on the assumption that the syntax is stored in reafferent connections from the auditory to the motor control area. Propagating synfire activity in the HVC (high vocal center) codes for individual syllables of the song and priming signals from the auditory network reduce the competition between syllables to allow only those transitions that are permitted by the syntax. Both imprinting of song syntax within HVC and the interaction of the reafferent signal with an efference copy of the motor command are sufficient to explain the gradual loss of syntax in the absence of auditory feedback. In the second part of this talk I will consider how the synfire chains assumed in the first part could develop. It has long been though that spike-timing dependent plasticity (STDP) provides an answer to the question of how the brain can develop functional structure in response to repeated stimuli. However, convincing demonstrations of this capacity in large, initially random networks have not been forthcoming; such demonstrations as there are typically rely on constraining the problem artificially. I will present a theoretical analysis based on a mean field approach of the development of feed-forward structure in random networks. An unstable fixed point in the recruitment dynamics prevents the stable propagation of structure in recurrent networks with weight-dependent STDP. The key theoretical predictions can be confirmed in large-scale simulations. The theory provides insight into the reasons why such development does not take place in unconstrained systems and enables the identification of candidate biologically motivated adaptations to the balanced random network model that might resolve the issue. Keywords: Plasticity and Learning Conference: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011, Freiburg, Germany, 4 Oct - 6 Oct, 2011. Presentation Type: Keynote Topic: other Citation: Morrison A (2011). Syntax, synfire, and synaptic plasticity: Modeling the generation of structure in birdsong and neuronal networks. Front. Comput. Neurosci. Conference Abstract: BC11 : Computational Neuroscience & Neurotechnology Bernstein Conference & Neurex Annual Meeting 2011. doi: 10.3389/conf.fncom.2011.53.00021 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 26 Sep 2011; Published Online: 04 Oct 2011. * Correspondence: Prof. Abigail Morrison, Bernstein Center Freiburg, Freiburg, Germany, morrison@fz-juelich.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Abigail Morrison Google Abigail Morrison Google Scholar Abigail Morrison PubMed Abigail Morrison Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.