Fig. 5. Time-lapse analysis of the migration of cortical neurons after culture on a glial cell layer for 3 days. (A) Histogram of the distance migrated by inhibitory (solid bars) and excitatory (open bars) neurons over a 10 hour period. (B) Images collected at 30 minute intervals of migrating inhibitory neurons. The neurons each possessed a leading process with a growth cone at the tip as well as a trailing process. Reversal of the direction of migration was accompanied by the disappearance of the growth cone from the original leading process and the appearance of a new growth cone at the tip of the previous trailing process. Bar, 20 µm.