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The action potential (AP) is transmitted by the concerted action of voltage-gated ion channels. Thermodynamic fluctuations in channel proteins produce probabilistic gating behavior, causing channel noise. Miniaturizing signaling systems increases susceptibility to noise, and with many cortical, cerebellar, and peripheral axons <0.5 mum diameter [1, 2 and(More)
It is generally assumed that axons use action potentials (APs) to transmit information fast and reliably to synapses. Yet, the reliability of transmission along fibers below 0.5 microm diameter, such as cortical and cerebellar axons, is unknown. Using detailed models of rodent cortical and squid axons and stochastic simulations, we show how conduction along(More)
Identifying the determinants of neuronal energy consumption and their relationship to information coding is critical to understanding neuronal function and evolution. Three of the main determinants are cell size, ion channel density, and stimulus statistics. Here we investigate their impact on neuronal energy consumption and information coding by comparing(More)
The only way we can interact with the world is through movements, and our primary interactions are via the hands, thus any loss of hand function has immediate impact on our quality of life. However, to date it has not been systematically assessed how coordination in the hand's joints affects every day actions. This is important for two fundamental reasons.(More)
THE ACTION POTENTIAL (AP), THE FUNDAMENTAL SIGNAL OF THE NERVOUS SYSTEM, IS CARRIED BY TWO TYPES OF AXONS: unmyelinated and myelinated fibers. In the former the action potential propagates continuously along the axon as established in large-diameter fibers. In the latter axons the AP jumps along the nodes of Ranvier-discrete, anatomically specialized(More)
Post-synaptic potential (PSP) variability is typically attributed to mechanisms inside synapses, yet recent advances in experimental methods and biophysical understanding have led us to reconsider the role of axons as highly reliable transmission channels. We show that in many thin axons of our brain, the action potential (AP) waveform and thus the Ca++(More)
The vast amounts of data which can be collected using body-sensor networks with high temporal and spatial resolution require a novel analysis approach. In this context, state-of-the-art Bayesian approaches based on variational, non-parametric or MCMC derived methods often become computationally intractable when faced with several million data points. Here,(More)
We investigate the effectiveness of a dual-channel MMG signal recorded from the biceps and triceps brachii as a way to predict the isometric forces produced by flexion and extension of the elbow. We asked 8 subjects to apply a range of isometric force levels for both flexion and extension of the elbow while the activity of the two muscles was captured using(More)
Optimal feedback control theory (OFCT) has been very successful in explaining human motor coordination in a principled manner [1,2]. OFCT derives motor control policies from the minimization of a cost function, which predicts a large variety of movement data [3]. However, very little is known about the nature of this cost function. From the many proposed(More)