SYMPOSIA at the NWG Meeting in Göttingen with Gollisch et al. and Leibold et al.
Symposia of the Bernstein Center Munich at the
8th GÖTTINGEN MEETING OF THE GERMAN NEUROSCIENCE SOCIETY
1. Tim Gollisch et al.: SYMPOSIUM 2, Thursday, 26 March, 2009, 9:00 – 12:00, Hall 105
„Neural computation by retinal circuits“
How do neuronal circuits extract and represent specific features of the sensory environment? This is a question of central interest in the study of brain function. To address it, the neural network of the vertebrate retina provides an extraordinary model system. Its well-established basic circuitry and good experimental accessibility together with precise control over its inputs offer us a unique basis to study neural computation and population coding. Early on, this paved the road for paradigmatic discoveries in neural processing, such as the structure of receptive fields and motion sensitivity, investigated by Hartline, Kuffler, Barlow and other pioneers in retina research. Today, the advent of new optical and electrical multi-neuron recording techniques allow us to extend these approaches from single cells to the population level and to study how different cell types in the retina contribute to particular computations. We are thus beginning to understand which aspects of the population activity encode different stimulus features and how individual circuit elements contribute to this neural code. This symposium will discuss recent examples of using the new experimental techniques to investigate how the retina computes different components of the visual scene. To start, Thomas Euler will provide insights into the computational power of dendritic processing in the retina. Subsequently, Thomas Münch and Michiel van Wyk will evaluate how retinal ganglion cells integrate dendritic signals to represent relevant visual information. The single cell investigations are taken to the population level in the talks of Michael Berry and Jutta Kretzberg who will focus on the encoding properties of visual stimuli by populations of retinal ganglion cells. Finally, Matthias Bethge’s talk will shine light on the teleological aspect of neural computation in the retina.
2. Christian Leibold et al. SYMPOSIUM 16, Saturday, 28 March, 2009, 9:00 - 12:00, Hall 9
„Multicellular representations of spatio-temporal perception and behaviour”
Behaving animals constantly perceive and autonomously interact with the world that surrounds them. To solve a complex behavioral task with propriate accuracy and temporal fidelity, their central nervous system has to integrate aspects of space and time and must compute meaningful neuronal representations thereof. In general, such representations are themselves spatio-temporal patterns manifest on a variety of scales, ranging from the cellular to the whole brain level. A key question of today’s systemic neuroscience is thus how these multicellular representations can be correctly interpreted and related to the resulting behavior. Researchers in a specific field of neuroscience usually tend to think about neuronal representations in terms of the classical paradigms that are established for their specific system and their specific technique. We believe that by comparing different aproaches to understanding multicellular activity patterns at various signal levels and in different systems, the symposium will facilitate the exchange of current ideas about the computations performed by neuronal populations and their relation to behavior in space and time. This symposium will combine theoretical and systems neurobiology and shall provide a comparative view of multi-neuronal activity patterns at different spatial and temporal scales across different systems of the mammalian brain. To set a theoretical frame, the symposium will open with a presentation by Wolfgang Maass on a theory that evaluates the computational power of a cortical microcircuit model on the basis of the inherent structural properties of the underlying network architecture. The next talk by Ken Harris will present a theory on how cellular assemblies can be formed by plastic processes employing retroaxonal signaling. In the following talk, Alexa Riehle will illustrate examples of how firing rate and spike synchrony encode in parallel the information related to planning and timing of actions in the motor cortex. Then, with Hans Super, the symposium will proceed to the next signal level of multi-unit responses in local populations of neurons in the visual cortex of the monkey. He will illustrate how these activity patterns are related to the perception and conscious detection of figures and their segregation from background. Finally, Ole Jensen will talk about activity patterns on an even larger scale thereby concluding the symposium with results that connect EEG patterns to working memory tasks and memory consolidation.
