A biophysical model of synaptic delay learning and temporal pattern recognition in a cerebellar Purkinje cell.
It has been suggested that information in the brain is encoded in temporal spike patterns which are decoded by a combination of time delays and coincidence detection. Here, we show how a multi-compartmental model of a cerebellar Purkinje cell can learn to recognise temporal parallel fibre activity patterns by adapting latencies of calcium responses after activation of metabotropic glutamate receptors (mGluRs). In each compartment of our model, the mGluR signalling cascade is represented by a set of differential equations that reflect the underlying biochemistry. Phosphorylation of the mGluRs changes the concentration of receptors which are available for activation by glutamate and thereby adjusts the time delay between mGluR stimulation and voltage response. The adaptation of a synaptic delay as opposed to a weight represents a novel non-Hebbian learning mechanism that can also implement the adaptive timing of the classically conditioned eye-blink response.
Steuber
Volker
V
Institute for Adaptive and Neural Computation, University of Edinburgh, 5 Forrest Hill, Edinburgh EH1 2QL, Scotland, UK. v.steuber@ucl.ac.uk
Willshaw
David
D
D000200:Action Potentials / Q000502:physiology; D000222:Adaptation, Physiological; D000818:Animals; D001703:Biophysics / Q000379:methods; D001767:Blinking / Q000502:physiology; D002118:Calcium / Q000378:metabolism; D002531:Cerebellum / Q000166:cytology* / Q000502:physiology; D003198:Computer Simulation; D003712:Dendrites / Q000502:physiology; D007858:Learning / Q000502:physiology*; D008959:Models, Neurological; D016571:Neural Networks, Computer; D009473:Neuronal Plasticity / Q000502:physiology; D010363:Pattern Recognition, Automated; D011689:Purkinje Cells / Q000166:cytology / Q000502:physiology*; D018094:Receptors, Metabotropic Glutamate / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology; D013569:Synapses / Q000502:physiology*; D013997:Time Factors
D018094:Receptors, Metabotropic Glutamate; D002118:Calcium