Tatyana Sharpee

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We propose a method that allows for a rigorous statistical analysis of neural responses to natural stimuli that are nongaussian and exhibit strong correlations. We have in mind a model in which neurons are selective for a small number of stimulus dimensions out of a high-dimensional stimulus space, but within this subspace the responses can be arbitrarily(More)
We propose a method that would allow for a rigorous statistical analysis of neural responses to natural stimuli, which are non–Gaussian and exhibit strong correlations. We have in mind a model in which neurons are selective for a small number of stimulus dimensions out of the high dimensional stimulus space, but within this subspace the responses can be(More)
One way to characterize neural feature selectivity is to model the response probability as a nonlinear function of the output of a set of linear filters applied to incoming signals. Traditionally these linear filters are measured by probing neurons with correlated Gaussian noise ensembles and calculating correlation functions between incoming signals and(More)
This paper compares a family of methods for characterizing neural feature selectivity with natural stimuli in the framework of the linear-nonlinear model. In this model, the neural firing rate is a nonlinear function of a small number of relevant stimulus components. The relevant stimulus dimensions can be found by maximizing one of the family of objective(More)
We show that in a magnetic field parallel to a two-dimensional ~2D! electron layer, strong electron correlations can change the rate of tunneling from the layer to the 3D continuum exponentially. It leads to a specific density dependence of the escape rate. The mechanism is a dynamical Mössbauer-type recoil, in which the Hall momentum of the tunneling(More)
There is an ongoing debate about whether the cause of dyslexia is based on linguistic, auditory, or visual timing deficits. The current investigation explores the theory that a common deficit underlies all of these processing problems in dyslexia: magno-parvocellular integration causing both selective and sustained attention deficits. To investigate this(More)
We provide a semiclassical theory of tunneling decay in a magnetic field and a three-dimensional potential of a general form. Because of broken time-reversal symmetry, the standard WKB technique has to be modified. The decay rate is found from the analysis of the Hamilton trajectories of the particle in complex phase space and time. In a magnetic field, the(More)
We consider the effect of electron correlations on tunneling from a 2D electron layer in a magnetic field parallel to the layer. A tunneling electron can exchange its momentum with other electrons, which leads to an exponential increase of the tunneling rate compared to the single-electron approximation. The effect depends on the interrelation between the(More)
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