Secretory vesicles tracked before and during secretagogue (Nicotine, 10 µM) stimulation were monitored and the type of motion mapped and compared. The percentages of caged vesicles (A, B and C), directed vesicles (D, E and F) and free vesicles (G, H and I) switching to caged (A, D and G), directed (B, E and H) or free (C, F and I) motion was calculated and compared in control and stimulated conditions. Observed percentages of switches in vesicle motion were mapped relative to the distance of the vesicle from the plasma membrane (J–R). The directionality of directed vesicles was established relative to the closest plasma membrane. Negative values represent vesicles travelling away from the membrane, whereas positive values denote those moving towards the plasma membrane. Null values represent vesicles that are directed transversally to the membrane. (S) Directed vesicles before stimulation (N = 7 cells, n = 234 vesicles). (T) Directed vesicles after stimulation (N = 7 cells, n = 157 vesicles).