Wednesday, January 26, 2011

Workshop CNS*2011 Stockholm (27-28, July 2011)

Reciprocal interactions of dynamical changes in network structure and function

Chair: Markus Butz and Arjen van Ooyen

Network structure determines the flow of electrical activity in every neural network and determines its functional and computational properties. Electrical activation of the neuron goes along with an intracellular increase in calcium which induces morphological alterations of the neuron on a slower time scale. Morphological changes, such as changes in dendritic spine and axonal bouton numbers as well as elongation, retraction and branching of axons and dendrites have direct impact on network connectivity (structural plasticity) even in the adult brain: As a consequence of morphological changes, synapses may break, new synapses can form and axonal branches can be re-routed. Rewired network connectivity, in turn, gives rise to an altered activity dynamic and may hold as a source for long term memory formation. Experimental data further support the notion that structural plasticity is not necessarily Hebbian-like but may serve as a neuronal mechanism to maintain electrical activity at a certain setpoint (neuronal homeostasis). Local structural changes at the single neuron compensating lasting disturbances in electrical activity may entail alterations in global network topology. Conversely, global topology can have impact on local compensation since certain network topologies may better support local structural plasticity mechanisms for maintaining neuronal homeostasis than others. These complex reciprocal interactions between structural changes and activity dynamics as well as local and global effects of structural plasticity necessitate theoretical modeling approaches to elucidate rapidly growing experimental data showing structural plasticity during memory formation and following brain lesions and degeneration. Therefore, the goal of this workshop is to bring together experimentalists and theoreticians in each session. Every session addresses one particular aspect of this topic and closes with a plenary discussion with all speakers of this session to integrate the different perspectives and approaches.


First Day morning session: Dynamics of intracellular calcium and single cell morphology

Times               Experimental:
9.00-9.30          Christian Lohmann , NIN Amsterdam (confirmed)

Topic: Calcium-induced changes in neuronal morphology and synapse formation
Literature: Lohmann C, Bonhoeffer T (2008) A role for local calcium signaling in rapid synaptic partner selection by dendritic filopodia. Neuron. 2008 Jul 31;59(2):253-60.

9.30-10.00         Naoyuki Inagaki, Nara Institute of Science and Technology, Ikoma, Japan (confirmed)
                        Topic: Signalling mechanisms for axon specification and growth regulation   
Literature: Inagaki N, Toriyama M, Sakumura Y (2010) Systems biology of symmetry-breaking during neuronal polarity formation. Dev Neurobiol. 2010 [Epub ahead of print]

10.15-10.45       Krasimira Tsaneva-Atanasova, Faculty of Engineering, University of Bristol (confirmed)
Topic: Mathematical biology of neuronal activity and calcium dynamics
Literature: Nowacki J, Osinga HM, Brown JT, Randall AD, Tsaneva-Atanasova KT (2010) A unified model of CA1/3 pyramidal cells: an investigation into excitability. Bristol Centre for Applied Nonlinear Mathematics (preprint)
10.45-11.15       Arjen van Ooyen, Neuroscience Campus, VU University Amsterdam (confirmed)
Topic: Computational models for neurite outgrowth 
Literature: Van Elburg, R. A. J., and Van Ooyen, A (2010) Impact of dendritic size and dendritic topology on burst firing in pyramidal cells. PloS Computational Biology 6(5): e1000781. doi:10.1371/journal.pcbi.1000781.

11.15-12.00       Discussion

Fist day afternoon session: Structural plasticity and neuronal homeostasis
Times               Experimental:
13.30-14.00       Tara Keck, MRC Centre for Developmental Neurobiology, King’s College London (confirmed)
Topic: Spine-dynamics in the visual cortex after deafferentation
Literature: Keck T, Mrsic-Flogel TD, Vaz Afonso M, Eysel UT, Bonhoeffer T, Hübener M (2008) Massive restructuring of neuronal circuits during functional reorganization of adult visual cortex. Nat Neurosci. 11(10):1162-7.                          
14.00-14.30       Vincenzo De Paola, MRC-Clinical Sciences Centre, Imperial College London (confirmed)
                        Topic: Structural plasticity of axonal branches and boutons
                        Literature: De Paola V, Holtmaat A, Knott G, Song S, Wilbrecht L, Caroni P, Svoboda K. (2006) Cell type-specific structural plasticity of axonal branches and boutons in the adult neocortex. Neuron 49(6):861-75.

14.45-15.15       Markus Butz, Neuroscience Campus, VU University Amsterdam (confirmed)
Topic: Activity-dependent structural plasticity induces cortical remapping
                        Literature: Butz M, van Ooyen A, Wörgötter F. (2009) A model for cortical rewiring following deafferentation and focal stroke. Front Comput Neurosci. 2009;3:10.
15.15-15.45       Moritz Deger, Bernstein Center, University Freiburg (confirmed)
Topic: Cooperative structural plasticity through local mechanisms at the dendritic spine
Literature: Helias, M.; Rotter, S.; Gewaltig, M.-O. & Diesmann, M. (2008) Structural plasticity controlled by calcium based correlation detection. Front Comput Neurosci 2 : 7

15.45-16.30              Discussion

Second day morning session: Structural plasticity and network topology

Times               Experimental:
9.00-9.30           Samora Okujeni, Bernstein Center, University of Fribourg (confirmed)
Topic: Network formation and topology of dissociated cell cultures
Literature: Tetzlaff C, Okujeni S, Egert U, Wörgötter F, Butz M. (2010) Self-organized criticality in developing neuronal networks. PLoS Comput Biol. 2010 Dec 2;6(12):e1001013.

9.30-10.00         Samuel Barnes, MRC for Neurodegeneration, King's College London (confirmed)
Topic: Experience-dependent rewiring of cortical networks
Literature: Cheetham Barnes SJ, Finnerty GT (2009) Sensory experience and cortical rewiring. Neuroscientist 16(2):186-98.

10.15-10.45       Armen Stepanyants, Northeastern University Physics Department, Dana Research Center Boston, MA (confirmed)
Topic: connectivity and topology of cortical networks        
Literature: Fares T, Stepanyants A. (2010) Cooperative synapse formation in the neocortex. Proc Natl Acad Sci U S A. 2009 Sep 22;106(38):16463-8. Epub 2009 Sep 4.

10.45-11.15       Marcus Kaiser, School of Computing Science, Newcastle University (confirmed)
Topic: A computational approach to brain topology 
Literature: Kaiser M, Hilgetag CC, Kötter R. (2010) Hierarchy and dynamics of neural networks. Front Neuroinformatics. 23;4.
11.15-11.45        Kees Stam, VU Medical Center Amsterdam (confirmed)
Topic: Impact of brain network topology in clinical application
Literature: Douw L, Schoonheim MM, Landi D, van der Meer ML, Geurts JJ, Reijneveld JC, Klein M, Stam CJ. (2010) Cognition is related to resting-state small-world network topology: an magnetoencephalographic study.Neuroscience. [Epub ahead of print]

11.45-12.30       Discussion

Second day afternoon session: Structural plasticity and memory formation

Times               experimental:
13.30-14.00       Sonja Hofer, Department of Neuroscience, University College London (confirmed)
Topic: Relating neuronal function to synaptic connectivity in visual cortex
Literature: Hofer SB, Mrsic-Flogel TD, Bonhoeffer T, Hübener M. (2009) Experience leaves a lasting structural trace in cortical circuits. Nature 457(7227):313-7.

14.00-14.30       Yi Zuo, MCD BIOLOGY Santa Cruz, CA (confirmed)
Topic: spine formation in motor learning
Literature: Xu T, Yu X, Perlik AJ, Tobin WF, Zweig JA, Tennant K, Jones T, Zuo Y. (2009) Rapid formation and selective stabilization of synapses for enduring motor memories. Nature 462(7275):915-9.

14.45-15.15       Andreas Knoblauch, Honda R&D, Offenbach (confirmed)
                        Topic: Memory formation in neural networks with structural plasticity
Literature: Knoblauch A, Palm G, Sommer FT. (2010) Memory capacities for synaptic and structural plasticity. Neural Comput 22(2):289-341.
15.15-15.45       Laurenz Wiskott, Institute for Neuroinformatics, Ruhr-University Bochum (confirmed)
Topic: Slow feature analysis as a possible learning mechanism for the visual cortex
Literature: Sprekeler H, Michaelis C, Wiskott L (2007) Slowness: An Objective for Spike-Timing–Dependent Plasticity? PLoS Comput Biol 3(6): e112. doi:10.1371/journal.pcbi.0030112.

15.45-16.30       Discussion


Dear colleagues, dear friends!

I have established this blog to keep you up-to-date with the preparation of our workshop in Stockholm without bothering you with emails. Furthermore, this blog may promote a lifely interaction and discussion on the topic - even before the workshop has begun.

Enjoy and feel free to contribute - your most recent paper hot of the press - or what else you might think is relevant!