Data Modelling for Analysis of Adaptive Changes in Fly Photoreceptors

Adaptation is a hallmark of sensory processing. We studied neural adaptation in intracellular voltage responses of the R1-R6 photoreceptors, of the fruit fly Drosophila, subjected to light patterns of naturalistic distribution at varying intensity levels. We use experimental data in a stepwise empirical modelling procedure to estimate a non-linear dynamical model (NARMAX) with variable gain. This model can describe accurately the observed adaptation process at each new level of changing light inputs. Generalized frequency response functions were used to visualize and quantify adaptation in the frequency domain.