Wavelet-Based Detection of Stimulus Responses in Time-Lapse Microscopy

Many experimental paradigms in biology aim at studying the response to coordinated stimuli. In dynamic imaging experiments, the observed data is often not straightforward to interpret and not directly measurable in a quantitative fashion. Consequently, the data is typically preprocessed in an ad hoc fashion and the results subjected to a statistical inference at the level of a population. We propose a new framework for analyzing time-lapse images that exploits some a priori knowledge on the type of temporal response and takes advantage of the spatial correlation of the data. This is achieved by processing the data in the wavelet domain and expressing the time course of each wavelet coefficient by a linear model. We end up with a statistical map in the spatial domain for the contrast of interest (i.e., the stimulus response). The feasibility of the method is demonstrated by an example of intrinsic microscopy imaging of mice's brains during coordinated sensory stimulation