Computational Neuroscience, ITB, Humboldt-University Berlin
Computational Neuroscience, ITB, Humboldt-University Berlin
This group focuses on computational neurobiology, in particular on the dynamics and signal processing capabilities of systems with spiking neurons.
Most neurons use action potentials, brief and uniform pulses of electrical activity, to transmit information. An action potential is generated when the membrane potential of a neuron reaches a threshold value. The action potential then travels down the axon toward synapses terminating at postsynaptic neurons where it initiates postsynaptic currents that summate to trigger (or inhibit) new action potentials.
A sequence, or `train', of action potentials may contain biologically relevant information based on rather diverse coding schemes. In motor neurons, for example, the strength at which an innervated muscle is flexed depends solely on the `firing rate', the average number of action potentials per unit time (a 'rate code'). At the other end of the spectrum lie complex temporal codes that use the precise timing of single action potentials. Such temporal codes may be locked to an external stimulus such as in the auditory system, or be generated intrinsically by the neural circuitry.
The wide range of coding schemes raises a number of questions. What is the temporal precision of signals sent out by a given neuron? Do all of its numerous postsynaptic target cells receive the same information? If not, what determines the individual signal? How can postsynaptic neurons read out the information? What is the functional relevance of correlations in the action potentials of several neurons? Which processes could generate the neural circuitry required for precise temporal codes? How can a signal based on the precise timing of action potentials be propagated from neuron to neuron? Questions of this kind are investigated by the group in various projects, ranging from data analysis to theoretical studies.
Synchronization processes and related dynamical phenomena in neural systems are being studied by a number of experimental groups in Berlin, opening up the possibility for close collaborations between theorists and experimentalists. Apart from the analysis of specific animal models, comparisons between different systems will lead to new insights about neural codes and their evolutionary history.
Most neurons use action potentials, brief and uniform pulses of electrical activity, to transmit information. An action potential is generated when the membrane potential of a neuron reaches a threshold value. The action potential then travels down the axon toward synapses terminating at postsynaptic neurons where it initiates postsynaptic currents that summate to trigger (or inhibit) new action potentials.
A sequence, or `train', of action potentials may contain biologically relevant information based on rather diverse coding schemes. In motor neurons, for example, the strength at which an innervated muscle is flexed depends solely on the `firing rate', the average number of action potentials per unit time (a 'rate code'). At the other end of the spectrum lie complex temporal codes that use the precise timing of single action potentials. Such temporal codes may be locked to an external stimulus such as in the auditory system, or be generated intrinsically by the neural circuitry.
The wide range of coding schemes raises a number of questions. What is the temporal precision of signals sent out by a given neuron? Do all of its numerous postsynaptic target cells receive the same information? If not, what determines the individual signal? How can postsynaptic neurons read out the information? What is the functional relevance of correlations in the action potentials of several neurons? Which processes could generate the neural circuitry required for precise temporal codes? How can a signal based on the precise timing of action potentials be propagated from neuron to neuron? Questions of this kind are investigated by the group in various projects, ranging from data analysis to theoretical studies.
Synchronization processes and related dynamical phenomena in neural systems are being studied by a number of experimental groups in Berlin, opening up the possibility for close collaborations between theorists and experimentalists. Apart from the analysis of specific animal models, comparisons between different systems will lead to new insights about neural codes and their evolutionary history.