Figure 1. Schematic of the movement time task.

Trial types are illustrated as a function of outcome valence (yellow for money trials and blue for shock trials) and presence or absence of a distractor (green flashing square). There were two possible outcomes in the money trials; ‘you have won 10 p’ or ‘you have not won 10 p’ and there were two possible outcomes for the shock trials; ‘you will now receive a shock’ or ‘you will now not receive a shock’. Subjects were exposed to 4 distinct trial types (see methods for details) comprising (i) money trial without distractor, (ii) money trial with distractor, (iii) shock trial without distractor, (iv) shock trial with distractor.