Figure 1.

Schematic of experimental trial for predator-prey task. (A) The nonthreat and threat conditions were separated by 12-second rest periods. (B, C) The nonthreat and threat conditions were explicitly conveyed via 2-second visual cues before each 30-second maze period. (D) The dual task was identical in both conditions: to maximize points by manipulating the movement of the avatar to capture prey (green squares), resulting in point gains, and to avoid capture by the predator (purple square), resulting in point losses. (E, F) Participants used a joystick to navigate an avatar (black square) through a two-dimensional maze. In the nonthreat condition, the blue background indicated no shocks would be administered at any time. In the threat condition, the red background indicated participants may receive a shock at any time. (G) Shock was randomly delivered on a subset of threat trials. To eliminate the confound of shock effects, only threat trials with no shock delivery were included in the threat versus nonthreat comparisons.