Figure 1.

Experimental procedure. (a) Sequencing of events for each trial in the learning task after trial initiation. Participants were presented with a random face from their allocated set of familiar faces (Set A or B), a noise mask, a second familiar face and a final noise mask before being required to respond ‘same’ (up-arrow key) or ‘different’ (down-arrow key). A randomly varying ISI of 0–400 ms occurred between presentations of the first noise mask and the second familiar face. (b) Sequencing of events for each trial in the recognition task. Once participants initiated a trial, they were presented with a random face from either their allocated set of familiar faces (Set A or B) or a novel face. After a noise mask, participants were required to respond whether the face was learnt (up-arrow key) or not learnt (down-arrow key). (c) Sequencing of events for each trial in the adaptation task, ending with a slider for the participants to indicate their attractiveness rating using the left- and right-arrow keys on the keyboard.