Determinants of retinal generators: wavelet analysis of electroretinographic signal

The electroretinogram (ERGs) is a commonly used diagnostic tool used in clinic to assess retinal diseases. Unfortunately, not much is know about what are the retinal cells that contribute to the signal. This greatly limits the amount of information that can be interpreted from the ERG signal and, consequently, limits its diagnostic power. We want to use a novel approach to understand how various parts of the ERG signal are generated by the retinal cells. To that purpose, different pharmacological agents that selectively block the activity of specific retinal cells will be injected in the eye of pigs (a very good model for human retina) maitained under deep anesthesia. ERGs wil be recorded the same way they are in humans. This should help determine what retinal cells are responsible to what particular part of the ERG signal. Furthermore, we will apply the Wavelet Transform, an elegant mathematical tool that allows the deconstruction of a signal in its principal components and compare the result of this analysis to the results of the pharmacological injections. This will allow us to determine what are the contributions of each retinal cells that can be "seen" in the signal and to elaborate a generic model of how the ERG signal is generated. This study will impact clinical electrodiagnostics but also all researches where non-invasive investigation of the retinal function is needed in animal models.