Abstract
Approach-avoidance motivations have been studied for decades but our understanding of motivation under dynamical environments is still limited. In this fMRI study, subjects (N = 30) played a predator-prey maze-navigation game. The game had six types of predator/prey characters (one type per trial), differentiated by color and shape, that had different chances of hurting or healing the player’s character. Subjects were instructed to approach prey or avoid predators to keep their health above zero. One predator and one prey character was designed to only hurt or only heal (non-conflict), whereas the other four characters could both hurt and heal with different probabilities (conflict). Subjects behaved as expected, avoiding non-conflict predators and approaching non-conflict prey and producing a mixture of approach/avoidance behaviors for conflict characters. A mass univariate whole brain analysis comparing the different character types was conducted. A contrast of avoiding predators > approaching prey showed significant upper-tail clusters in dorsal attention network and dorsal striatum and lower-tail clusters in default mode network. Upper-tail clusters overlapped with the conjunction of predator > rest & prey > rest and lower-tail clusters overlapped with the conjunction of predator < rest & prey < rest. Thus, predators produced stronger activation and “deactivation” than prey in regions that were “activated” and “deactivated” by playing the game. A contrast of conflict > non-conflict characters showed upper-tail clusters in regions that matched central executive network. In conclusion, that gameplay-(de)activated regions were the same for predator and prey suggests that approach and avoidance motivation systems are overlapping. Although dorsal attention network, dorsal striatum, and default network showed differences between predator and prey characters, the differences could be explained by consistently stronger (de)activation by predators than prey. Lastly, gameplay with conflict characters recruited regions in central executive network suggests that coactivation of approach-avoidance motivation produces extra demands.