Computer-simulated analysis of cell migration was attempted with the aim of improving the discriminative characterization of the in vitro locomotory behaviour of normal and neoplastic cells and verifying a concept of cell movement regulation proposed earlier. It suggested that cell membrane activity and distribution of resting periods along the cell trajectory could be introduced with advantage among the migration parameters; this appeared to be a promising refinement on the standard methodology. Moreover, it was inferred that setting up critical, instead of optimal, conditions for cells in culture should reveal behavioural differences otherwise hidden.