Figure 1.

Layout of simulated environment and different experimental treatments. (a) Layout of the simulated environment. In the first task, participants started at the initial position ‘St’, followed arrows to the entrance ‘En’ into the central room ‘CR’ and to the first target ‘T1’. The second task is outlined in the Material and methods and did not involve any simulated pedestrian movement. In the third task, participants started at ‘T1’ and subsequently left ‘CR’ through either exit into corridors ‘C1’ or ‘C2’ and moved to the final target ‘T2’. The entrance ‘En’ was blocked in this task. The pedestrian steered by participants is represented by a black filled circle, located at ‘T1’, and simulated pedestrians are represented by white filled circles with a line indicating their movement direction. We show the control treatment in which the simulated crowd splits evenly between the two exits during the third task. For illustration purposes, the whole environment is visible, but participants had a limited view as shown in the other panels. (b) Memory treatment M (the message displayed translates to: ‘Well done! During an emergency, leave the room through the exit marked with the following symbol: @’). (c) Crowd treatment C (the entire crowd exits through one exit). (d) Sign treatment S (the crowd splits evenly between the two exits and a sign labelled ‘EXIT’ indicates which exit to use). (Online version in colour.)