title: A pulsed neural network model of bursting in the basal ganglia.
abstract: We present new techniques for extending the functionality of spiking neurons which allow the incorporation of several aspects of neuron function previously confined to the domain of low level ion-channel based models. These aspects include spontaneous (or endogenous) firing, the complex interaction of multiple ion-species and the spatial distribution of synaptic contacts over the cell membrane. These ideas are applied to a neural circuit consisting of the cortex and a subset of the nuclei in the basal ganglia-the subthalamic nucleus (STN) and the external segment of the globus pallidus (GPe). This circuit has been studied extensively in vitro by Plenz and Kitai [Plenz, D., & Kitai, S. T. (1999). A basal ganglia pacemaker formed by the subthalamic nucleus and external globus pallidus. Nature, 400 677-682] whose data we use to constrain our model. With respect to this circuit, we have obtained three main results. First, that its characteristic burst firing is due to a Ca2+ current mediated mechanism. Second, that noise can assist in the generation of bursting and, paradoxically, stabilise the network behaviour under synaptic weight variations. Third, that a variety of dendritic processing is necessary in order to obtain the full range of bursting behaviour.
authors.affiliation: Department of Psychology, University of Sheffield, UK. m.d.humphries@shef.ac.uk
authors.forename: M D
authors.initials: MD
authors.lastname: Humphries
authors.forename: K N
authors.initials: KN
authors.lastname: Gurney
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000818:Animals; D001369:Axons / Q000502:physiology; D001479:Basal Ganglia / Q000502:physiology*; D001683:Biological Clocks / Q000502:physiology; D001921:Brain / Q000502:physiology; D015220:Calcium Channels / Q000502:physiology; D002451:Cell Compartmentation / Q000502:physiology; D003712:Dendrites / Q000502:physiology; D006801:Humans; D009415:Nerve Net / Q000502:physiology*; D016571:Neural Networks, Computer; D009434:Neural Pathways / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D013569:Synapses / Q000502:physiology; D009435:Synaptic Transmission / Q000502:physiology*
chemical_list: D015220:Calcium Channels