Spindle Waves In Vitro are Propagating Oscillations
The simultaneous extracellular recording from eight multiple-unit electrodes reveal that spindle waves propagate through the slice, in a dorsal to ventral or ventral to dorsal direction, at the rate of about 1 mm per second, or about 100 microns per burst of activity.
see Kim, U., Bal, T., and McCormick, D.A. (1995) Spindle waves are propagating synchronized oscillations in the ferret LGNd in vitro. Journal of Neurophysiology, 74, 1301-1323.