A reverse in the direction of tangential movement of a granule cell in the bottom level of the EGL. A, The horizontally oriented cell body (white asterisks) of the granule cell initially moved toward the left hemisphere at a rate of 14.6 μm/hr, and 80 min later, changed its direction of movement and started to migrate toward the right hemisphere at a rate of 17.9 μm/hr. Black circles represent a reference point. Time interval (in minutes) is indicated on the bottom rightof each photograph. Scale bar, 10 μm. The total distance traversed by the granule cell soma (B), the direction and distance traveled by the soma during each 10 min of the testing period (C), and the length/width ratio of the soma (D) were plotted as a function of elapsed time. In B and C, positive values represent cell movement toward the left hemisphere, and negative values represent cell movement toward the right hemisphere.