title: Reliable neuronal systems: the importance of heterogeneity.
abstract: For every engineer it goes without saying: in order to build a reliable system we need components that consistently behave precisely as they should. It is also well known that neurons, the building blocks of brains, do not satisfy this constraint. Even neurons of the same type come with huge variances in their properties and these properties also vary over time. Synapses, the connections between neurons, are highly unreliable in forwarding signals. In this paper we argue that both these fact add variance to neuronal processes, and that this variance is not a handicap of neural systems, but that instead predictable and reliable functional behavior of neural systems depends crucially on this variability. In particular, we show that higher variance allows a recurrently connected neural population to react more sensitively to incoming signals, and processes them faster and more energy efficient. This, for example, challenges the general assumption that the intrinsic variability of neurons in the brain is a defect that has to be overcome by synaptic plasticity in the process of learning.
authors: Institute of Theoretical Computer Science, ETH Zürich, Zürich, Switzerland.
authors: Johannes
authors: J
authors: Lengler
authors: Florian
authors: F
authors: Jug
authors: Angelika
authors: A
authors: Steger
mesh_terms: D000818:Animals; D001921:Brain / Q000502:physiology; D003198:Computer Simulation; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology; D018740:Genetic Heterogeneity; D006801:Humans; D007858:Learning / Q000502:physiology; D008959:Models, Neurological; D009415:Nerve Net / Q000502:physiology*; D009473:Neuronal Plasticity / Q000235:genetics*; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D016012:Poisson Distribution; D018091:Receptors, AMPA / Q000235:genetics / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000235:genetics / Q000378:metabolism; D013569:Synapses / Q000502:physiology; D009435:Synaptic Transmission / Q000502:physiology; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000378:metabolism; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D018091:Receptors, AMPA; D016194:Receptors, N-Methyl-D-Aspartate; D005680:gamma-Aminobutyric Acid; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid