Calcium Green-1 dextran (10kD) was used to stain the olfactory bulb. Changes of fluorescence intensity were recorded with a NeuroCCD-SM256; resolution = 128X128 . A. The three maps were made at the three times shown by the black arrows in section B. The maps change with time reflecting the fact that the time course of signals differ from glomerulus to glomerulus. B. Time course of the calcium signals from three different glomeruli (pointed to by arrows of same colors).