Figure 1.
Human Approach-Avoidance Computer Game and Hemodynamic Responses to Threat Level
(A) The human player (green triangle) forages for tokens (yellow rhombi) on a 24 × 16 grid. One of three differently dangerous predators (threat levels denoted by different frame colors) looms in a corner of the grid (gray circle).
(B) Collected tokens appear on the grid and are paid out for money at the end of the game.
(C) The predator can wake up any time and chase the human player. The human player can hide in the safe place (black grid block).
(D) If caught, the human player looses all tokens from this epoch, and the epoch is over.
(A–D) The possibility of a chase phase (C and D) provides avoidance motivation during the foraging phase (A and B). We report behavior during the foraging phase.
(E) Blood-oxygen-level-dependent (BOLD) responses to threat level: activation in the left anterior hippocampus, the human homolog of the rodent ventral hippocampus (cluster peak T = 4.95 at −27/−6/−24 mm MNI, 74 voxels, p < 0.05 small-volume corrected for family-wise error across the region of interest, overlaid on group average T1-weighted image in MNI space, x = −29 mm). See Figure S1 for additional whole-brain analysis.
(F) Estimated BOLD activity in the hippocampus cluster for the three threat levels, individually adjusted for BOLD activity at medium threat level. Error bars indicate the SEM difference between low and medium or high and medium threat level.