Authors:
Pedro Tomás
;
João Martins
and
Leonel Sousa
Affiliation:
INESC-ID / IST TU Lisbon, Portugal
Keyword(s):
Retina Models, Stochastic Leaky Integrate and Fire, Poisson-based model, Dynamic model.
Related
Ontology
Subjects/Areas/Topics:
Applications and Services
;
Biomedical Engineering
;
Biomedical Signal Processing
;
Computer Vision, Visualization and Computer Graphics
;
Medical Image Detection, Acquisition, Analysis and Processing
;
Physiological Processes and Bio-Signal Modeling, Non-Linear Dynamics
Abstract:
Many models have been proposed to describe the visual processing mechanisms in the retina. The spike generation mechanism of the models is typically performed by a Poisson process. Alternatively, a more realistic approach can be used by implementing an integrate and fire mechanism. In this paper we show that the Stochastic Leaky Integrate and Fire (SLIF) model is equivalent to a non-linear Poisson-based model. Furthermore, it proposes a dynamic model for the retina visual processing path, achieved through modulations. For estimating this model a two-step approach is proposed: i) an initial estimation is computed by using a spike-triggered analysis, and ii) the likelihood of the spike train is maximised by gradient ascent.