Blind signal separation from optical imaging recordings with extended spatial decorrelation

Optical imaging is the video recording of two-dimensional patterns of chang es in light reflectance from cortical tissue evoked by stimulation. We derived a method, extended spatial decorrelation (ESD), that uses second -order statistics in space for separating the intrinsic signals into the st imulus related components and the nonspecific variations. The performance o f ESD on model data is compared to independent component analysis algorithm s using statistics of fourth and higher order, Robustness against sensor no ise is scored. When applied to optical images, ESD separates the stimulus specific signal well from biological noise and artifacts.