Computational Neuroscience
Florentin Wörgötter
The BCCN-group on Computational Neuroscience is mainly interested in understanding neuronal systems embedded in their environment.
Over decades neurons and brains have mainly been investigated as stimulus-response systems, where the output of the system does not affect its own inputs. Animals (and humans), however, operate differently in quite a fundamental way: Whatever action we perform, it will almost always immediately affect our sensory inputs. In writing these lines I see my fingers moving over the keyboard, feel their touch, hear the clicking of the keys, notice letters appezring bksp bksp bksp bksp bksp appearing, where every typo (feedback error-signal) will enact a correction closing the perception-action loop.
Hence, such perception-action loops are the normal mode of operation of all animals. Within such a loop some signals that come back to the animal’s sensors are of direct relevance (like the seeing of a typo in writing), while others do not immediately drive the loop (like the clicking of the keys).
Fundamentally, it is only the animal/human/agent who can decide which of the arriving sensor signals are relevant for the momentarily existing task and which are not. The behaviour of any creature is therefore controlled by measuring its own inputs (input-control) and normally not by reinforcement from an external observer1. Improved fitness will arise if an animal can do this in a predictive way, hence if it can use predictive mechanisms to anticipate the outcome of its own actions and, to some degree, also the “behaviour of the world”.
Our research agenda: The goal of our studies is to understand how autonomous behaviour arises in animals and agents through the development of complex perception-action loops and the learning of adaptive, anticipatory behaviour through input-control with minimal external interference.
To this end we investigate (using neuro-physiological data as well as robots):
Input: Information processing in the visual system and its use in machine vision.
Adaptation: The biophysics of synaptic plasticity and correlation based learning mechanisms in animals and robots.
Reasoning: Decision making, planning and the discovery of the structure of the agent’s environment.
Output: The sequencing of actions towards goal-directed behaviour.
We believe that every external reinforcement will first by the
animal transformed into an internal signal, measured and compared to
other possible inputs of relevance, before it might or might not be
used to influence behaviour and/or learning.
Lectures:
- Computational Neuroscience for Informatics SS
- Computational Neuroscience for Biology SS
- Computational Neuroscience - Learning
- Seminar Computational Neuroscience SS 2008
Projects involved:
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Homeostasis LearningContact person: Kolodziejski, ChristophAdaptive neuronal systems learn to avoid a disturbance and therefore keep homeostasis are constructed and investigated in this project.
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Goal-directed Learning (learning to achieve a goal)Contact person: Kolodziejski, ChristophHow can non-goal directed signals from the environment be combined and be utilized to achieve goal directed behaviour? This is the main question this project is faced with.
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Modelling spike-timing dependent plasticity.Contact person: Wörgötter, FlorentinSpike-timing dependent plasticity is related to the differential Hebbian learning rule, which we use also for controlling robots (ISO/ICO rule). This relation can be used to derive a flexible formalism that allows modelling STDP in an efficient way. Thus, we can now investigate STDP local at dendrites or the change of STDP as a consequence of pre- and post-synaptic parameter.
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Adaptive - Fast Dynamic Walking Robot “RUNBOT”Contact person: Manoonpong, PoramateThe goal of this roject is to design a dynamic, biomechanical system for bipedal walking under neural control and learning. This has led to RunBot, which achieves a speed of about 3.5 leg-length per second and is currently the fastest planar, dynamic, biped robot, which can learn to adapt to the terrain.
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Philosophy, The Arts and Public Awareness of ScienceContact person: Wörgötter, FlorentinThis project addresses aspects, which are usually not in the center of interest of a natural scientist. Still, every now and then, we found ourselves in a position that we felt the need to “think a bit beyond” the data and the quantifications treated and performed done in our daily business and to deal with issues of wider interest. Several publications have arisen from this, addressing issues of “mind and body”, which should be – at least – an interesting read hopefully stimulating discussions and some more “thoughts-beyond”.
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