I’m accessing data from a functional_connectivity neuropixel data session. Looking at the dot_motion stimulus I can’t decipher the speed information. Looking at the white paper it reads:
Last, a dot motion stimulus consisting of approximately 200 1.5º radius white dots on a mean-luminance gray background moving at one of 7 speeds (0º/s, 16º/s, 32º/s, 64º/s, 128º/s, 256º/s, 512º/s)
however when I look at the stimulus table, the speed parameter doesn’t seem to match.
dmtable = session.get_stimulus_table(['dot_motion']) dmtable['Speed'].unique()
array([0.02, 0.005, 0.01, 0.001, 'null'], dtype=object)
There only seems to be 4 + 1 speeds (assuming null = 0 deg/s). Moreover, it’s not clear what the units here indicate. My guess is they are normalised to screen co-ordinates?
Is this the correct stimulus info for the dot_motion stimulus?
Finally, is there any more detailed info about how the stimulus was generated? I’ve had a look around but can’t find anything more detailed than the white paper.