Procedure 1: determining the profile of temperature modification produced by light patterns
The thermal modifications produced by the different stimulation patterns was determined by placing the thermal probe on the surface of OB slices at the center of the objective field. Each pattern was repeated 10 times (interstimulus time: 10 s) and the median normalized temperature trace was used to calculate the temporal profile of temperature variation for each pattern in each slice. This procedure was repeated on 10 different slices and the comparison between patterns was performed on the average trace (± 95% confidence interval).
The following experimental procedures 2, 3 and 4 were applied to each recorded neuron.