Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Reconstruction of Sensory Stimuli Encoded with Integrate-and-Fire Neurons with Random Thresholds | Hindawi Publishing Corporation EURASIP Journal on Advances in Signal Processing Volume 2009 Article ID 682930 14 pages doi 2009 682930 Research Article Reconstruction of Sensory Stimuli Encoded with Integrate-and-Fire Neurons with Random Thresholds Aurel A. Lazar and Eftychios A. Pnevmatikakis Department of Electrical Engineering Columbia University New York NY 10027 USA Correspondence should be addressed to Eftychios A. Pnevmatikakis eap2111@ Received 1 January 2009 Accepted 4 April 2009 Recommended by Jose Principe We present a general approach to the reconstruction of sensory stimuli encoded with leaky integrate-and-fire neurons with random thresholds. The stimuli are modeled as elements of a Reproducing Kernel Hilbert Space. The reconstruction is based on finding a stimulus that minimizes a regularized quadratic optimality criterion. We discuss in detail the reconstruction of sensory stimuli modeled as absolutely continuous functions as well as stimuli with absolutely continuous first-order derivatives. Reconstruction results are presented for stimuli encoded with single as well as a population of neurons. Examples are given that demonstrate the performance of the reconstruction algorithms as a function of threshold variability. Copyright 2009 A. A. Lazar and E. A. Pnevmatikakis. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. 1. Introduction Formal spiking neuron models such as integrate-and-fire IAF neurons encode information in the time domain 1 . Assuming that the input signal is bandlimited and the bandwidth is known a perfect recovery of the stimulus based upon the spike times can be achieved provided that the spike density is above the Nyquist rate 2 . These results hold for a wide variety of sensory stimuli including audio 3 and video 4 encoded with a population of IAF .
