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Circuit Mechanisms of Memory Formation Neural Plasticity Circuit Mechanisms of Memory Formation Guest Editors: Björn M. Kampa, Anja Gundlfinger, Johannes J. Letzkus, and Christian Leibold Circuit Mechanisms of Memory Formation Neural Plasticity Circuit Mechanisms of Memory Formation Guest Editors: Bjorn¨ M. Kampa, Anja Gundlfinger, Johannes J. Letzkus, and Christian Leibold Copyright © 2011 Hindawi Publishing Corporation. All rights reserved. This is a special issue published in volume 2011 of “Neural Plasticity.” All articles are open access articles distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Editorial Board Robert Adamec, Canada Anthony Hannan, Australia Vilayanur S. Ramachandran, USA Shimon Amir, Canada George W. Huntley, USA Kerry J. Ressler, USA Michel Baudry, USA Yuji Ikegaya, Japan Susan J. Sara, France Michael S. Beattie, USA Leszek Kaczmarek, Poland Timothy Schallert, USA Clive Raymond Bramham, Norway Jeansok J. Kim, USA Menahem Segal, Israel Anna Katharina Braun, Germany Eric Klann, USA Panagiotis Smirniotis, USA Sumantra Chattarji, India Małgorzata Kossut, Poland Ivan Soltesz, USA Robert Chen, Canada Frederic Libersat, Israel Michael G. Stewart, UK David Diamond, USA Stuart C. Mangel, UK Naweed I. Syed, Canada M. B. Dutia, UK Aage R. Møller, USA Donald A. Wilson, USA Richard Dyck, Canada Diane K. O’Dowd, USA J. R. Wolpaw, USA Zygmunt Galdzicki, USA A. Pascual-Leone, USA Chun-Fang Wu, USA PrestonE.Garraghty,USA Maurizio Popoli, Italy J. M. Wyss, USA Paul E. Gold, USA Bruno Poucet, France Lin Xu, China Manuel B. Graeber, Australia Lucas Pozzo-Miller, USA Min Zhuo, Canada Contents Circuit Mechanisms of Memory Formation,Bjorn¨ M. Kampa, Anja Gundlfinger, Johannes J. Letzkus, and Christian Leibold Volume 2011, Article ID 494675, 2 pages The Many Forms and Functions of Long Term Plasticity at GABAergic Synapses, Arianna Maffei Volume 2011, Article ID 254724, 9 pages The Role of GABAergic Inhibition in Ocular Dominance Plasticity, J. Alexander Heimel, Danielle¨ van Versendaal, and Christiaan N. Levelt Volume 2011, Article ID 391763, 11 pages Presynaptic Ionotropic Receptors Controlling and Modulating the Rules for Spike Timing-Dependent Plasticity, Matthijs B. Verhoog and Huibert D. Mansvelder Volume 2011, Article ID 870763, 11 pages Histaminergic Mechanisms for Modulation of Memory Systems, Cristiano AndreK´ ohler,¨ Weber Claudio´ da Silva, Fernando Benetti, and Juliana Sartori Bonini Volume 2011, Article ID 328602, 16 pages A Neural Correlate of Predicted and Actual Reward-Value Information in Monkey Pedunculopontine Tegmental and Dorsal Raphe Nucleus during Saccade Tasks, Ken-ichi Okada, Kae Nakamura, and Yasushi Kobayashi Volume 2011, Article ID 579840, 21 pages Neuroplasticity of the Sensorimotor Cortex during Learning, Joseph Thachil Francis and Weiguo Song Volume 2011, Article ID 310737, 11 pages Motor Cortical Networks for Skilled Movements Have Dynamic Properties That Are Related to Accurate Reaching, David F. Putrino, Zhe Chen, Soumya Ghosh, and Emery N. Brown Volume 2011, Article ID 413543, 15 pages Cortical Plasticity during Motor Learning and Recovery after Ischemic Stroke, Jonas A. Hosp and Andreas R. Luft Volume 2011, Article ID 871296, 9 pages Reactivation, Replay, and Preplay: How It Might All Fit Together, Laure Buhry, Amir H. Azizi, and Sen Cheng Volume 2011, Article ID 203462, 11 pages Ripples Make Waves: Binding Structured Activity and Plasticity in Hippocampal Networks, Josef H. L. P. Sadowski, Matthew W. Jones, and Jack R. Mello Volume 2011, Article ID 960389, 11 pages Place Cells, Grid Cells, Attractors, and Remapping, Kathryn J. Jeffery Volume 2011, Article ID 182602, 11 pages Associative Memory Storage and Retrieval: Involvement of Theta Oscillations in Hippocampal Information Processing, Federico Stella and Alessandro Treves Volume 2011, Article ID 683961, 15 pages Interplay of Amygdala and Cingulate Plasticity in Emotional Fear, Hiroki Toyoda, Xiang-Yao Li, Long-Jun Wu, Ming-Gao Zhao, Giannina Descalzi, Tao Chen, Kohei Koga, and Min Zhuo Volume 2011, Article ID 813749, 9 pages Hindawi Publishing Corporation Neural Plasticity Volume 2011, Article ID 494675, 2 pages doi:10.1155/2011/494675 Editorial Circuit Mechanisms of Memory Formation Bjorn¨ M. Kampa,1 Anja Gundlfinger,1 Johannes J. Letzkus,2 and Christian Leibold3 1 Department of Neurophysiology, Brain Research Institute, University of Zurich, 8057 Zurich, Switzerland 2 Friedrich Miescher Institute for Biomedical Research, Maulbeerstraße 66, 4058 Basel, Switzerland 3 Department of Biology II, University of Munich, 82152 Planegg-Martinsried, Germany Correspondence should be addressed to Bjorn¨ M. Kampa, [email protected] Received 25 October 2011; Accepted 25 October 2011 Copyright © 2011 Bjorn¨ M. Kampa et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 1. Introduction visual input through one eye leads to the dominance of the contralateral eye’s inputs. This also changes the ocular Memory formation is one of the most fascinating and preference of cortical neurons during the sensitive period. complex brain functions. A large body of research over the One of the central mechanisms responsible for opening the last decades has drastically increased our understanding of sensitive period is the maturation of inhibitory innervation, the molecular and cellular processes underlying learning, which may also involve plasticity of inhibitory inputs. most notably through a detailed investigation of synaptic The many forms and functions of long-term plasticity at plasticity. This reductionist approach, typically involving GABAergic synapses are reviewed by A. Maffei. New exper- in vitro experiments, has been tremendously successful in imental work has demonstrated that inhibitory synapses also providing a mechanistic framework for learning at the undergo plastic changes and follow their own learning rules. level of single neurons. However, real-life memories are formed through dynamic interactions of many neurons Understanding these rules is crucial to fully comprehend the embedded in large networks. Investigating the mechanisms circuit mechanisms of memory formation. and consequences of learning at the level of neuronal circuits is technically much more demanding, and we are only 3. Neuromodulation of Learning and Memory beginning to understand this important topic. This special issue presents recent progress in illuminating the most The effect of long-range neuromodulatory inputs on local exciting issues in the field of circuit mechanisms of memory circuit computations is at present a very dynamic field of formation. The contributing articles cover essential concepts investigation, in particular since neuromodulation is well and hypotheses underlying memory formation ranging from known to be critical for many forms of learning. The cho- synaptic mechanisms of plasticity in neuronal microcircuits linergic system is implicated in gating cortical plasticity to circuit reorganizations in response to physiological and during associative learning and sensory map plasticity. M. pathological influences. B. Verhoog and H. D. Mansvelder review how cholinergic modulation acting via presynaptic ionotropic receptors may 2. Plasticity of Inhibitory Circuits create brief time windows for synaptic modulation during spike-timing-dependent plasticity. C. Kohler¨ et al. address Neuronal circuits are assembled by intricately interconnected the modulation of hippocampal and neocortical memory excitatory and inhibitory units. The balance of excitation and systems by the relatively little known neuromodulator hista- inhibition is absolutely critical to circuit function. The lion’s mine. They provide an overview of the anatomy of histamin- share of research into plasticity has focused on excitatory ergic systems, histamine metabolism, receptors, and turnover synapses. However, GABAergic inhibition in the cortex plays and introduce the involvement of histamine in synaptic a major role in development and ocular dominance plasticity plasticity. Finally, K. Okada et al. discuss how a prominent as reviewed by Heimel et al. Sensory deprivation of the neuromodulatory signal during learning, the dopaminergic 2 Neural Plasticity prediction error signal, is computed with a special emphasis could underlie this phenomenon. A particular emphasis is on the involvement of other neuromodulatory systems. laid on how activity patterns can be transmitted between the different hippocampal and extrahippocampal regions 4. Motor Learning during sharp wave oscillations and how synaptic plasticity may benefit from this dynamical state. K. J. Jeffery then Circuit plasticity in sensorimotor areas has become a major introduces the reader to the general concepts and use interest since the recent introduction of brain-machine inter- of discrete and continuous attractor networks involved faces. Focusing on motor learning in the rat, J. Francis and in spatial navigation. She reviews the evidence for the W. Song discuss plasticity mechanisms on the behavioral, existence of such attractor networks and finally presents a neurophysiological, and synaptic levels. In addition, the hypothesis—on modeling and experimental work—on how authors present data on the inhibition of protein kinase partial remapping and attractor dynamics can coexist in the Mζ, which
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