Screenshots of the ‘liking’ task.

Participants were initially presented with a face image and a visual analogue scale (left) and were given 5 seconds to rate the image (right). The ‘wanting’ task was visually similar, except that the labels ‘very attractive’ and ‘very unattractive’ were absent, and the height of the white bar of the visual analogue scale decreased over time (the speed of this movement could be either increased or decreased by key-pressing).