Figure 3
Schematic depiction of the effort allocation task. First, fixation cross is shown, followed by the reward cue. To earn reward, participants have to keep a ball above the red line by repeatedly pressing a button with their right index finger. Reward magnitude (low vs. high), difficulty (easy vs. hard), and reward type (food vs. money) were manipulated as task conditions. The lower left graph shows a representative time series of a high-difficulty trial, depicting effort output as button press rate, BPR, in % relative to the maximum frequency of the participant. Invigoration slopes captured how quickly participants reach effortful behavior during a trial to collect the reward. Effort maintenance relates to the average relative frequency on the trial. Figure taken from14 under CC BY license (https://creativecommons.org/licenses/by/4.0/); no changes have been made to the figure.
