Table 1.
An overview of selected studies using the EEfRT: Modifications, reliability, and validity (chronological order).
Fig 1.
Schematic illustration of one trial of the original EEfRT.
A fixation cross (1s, A) is followed by a screen showing probability of reward attainment and reward magnitude for the easy and the hard task (B), lasting until the participant made a choice which task to complete but no longer than 5s. Then, after presentation of a ready–screen (1s, C) the main screen for the trial showing a red bar that fills with each button press is presented until the task is completed or until the trial time is over (D). Finally, task completion is signaled (2s, E) and a feedback screen shows the amount of money won (2s, F).
Fig 2.
Schematic illustration of one trial of the modified EEfRT.
A fixation cross (1s, A) is followed by a screen showing probability of reward attainment and reward magnitude per click for 3s (B). Then, after presentation of a ready–screen (1s, C), the main screen for the trial showing a red bar that grows with each click is presented alongside a scale, indicating the current monetary gain and a countdown (20s, D). Finally, task completion is signaled (1.5s, E) and a feedback screen shows the amount of money won (2s, F).
Table 2.
Internal consistencies and reliabilities for questionnaires and both versions of the EEfRT in Study 1 and 2.
Fig 3.
Percentage of hard-task-choices (HTC) within the original EEfRT in Study 1.
Comparison of trials with low probability of reward attainment (left; A), medium probability of reward attainment (middle; B) and high probability of reward attainment (right, C) within the original EEfRT. For each probability category all three categories of reward magnitude (low / medium / high) are displayed. Data points are added as dots for individual scores. Error bars depict a 95% confidence interval (CI) of the mean.
Table 3.
GEE models for basic predictors of percentage of hard-task choices within the original EEfRT in Study 1 and 2 and of mean number of clicks within the modified EEfRT in Study 1.
Fig 4.
Mean number of clicks within the modified EEfRT in Study 1.
Comparison of trials with low probability of reward attainment (left; A), medium probability of reward attainment (middle; B) and high probability of reward attainment (right; C) within the modified EEfRT. For each probability category all 5 different reward magnitudes (ranging from 1 cent (most left) to 5 cent (most right) are displayed. Data points are added as dots for individual scores. Error bars depict a 95% confidence interval (CI) of the mean.
Fig 5.
Percentage of hard task choices (HTC) within the original EEfRT in Study 2.
Comparison of trials with low probability of reward attainment (left; A), medium probability of reward attainment (middle; B) and high probability of reward attainment (right; C) within the original EEfRT. For each probability category, all three reward magnitude categories (low / medium / high) are displayed. Data points are added as dots for individual scores. Error bars depict a 95% confidence interval (CI) of the mean.
Fig 6.
Pearson correlations between trait BAS scores (z-standardized) and task performance (Study 1 and 2).
Correlations for the mean number of clicks within trials with low probability of reward attainment in the modified EEfRT (A: Study 1) and percentage of hard task choices within trials with low probability of reward attainment in the original EEfRT (B: Study 1; C: Study 2). All depicted correlations were nonsignificant with p >.05.
Table 4.
Correlations between the original EEfRT (percentage of hard-task -choices), the modified EEfRT (mean number of clicks) and trait variables (Study 1 and 2).
Table 5.
Correlations between the original EEfRT (percentage of hard-task -choices), the modified EEfRT (mean number of clicks) and trait variables (Study 1 and 2).
Fig 7.
Pearson correlations between task performance in both tasks in Study 1.
Correlations between the percentage of hard-task-choices (HTC %) within the original EEfRT and the mean number of clicks within the modified EEfRT for A: Trials with low probability of reward attainment (= 12%), B: Medium probability of reward attainment (= 50%) and C: High probability of reward attainment (= 88%). All depicted correlations were significant with p < .05.
Table 6.
Zero-order correlations between the original EEfRT (percentage of hard-task -choices) and the modified EEfRT (mean number of clicks) for different probabilities of reward attainment and different reward magnitudes.
Table 7.
Zero-order correlations between the original EEfRT (percentage of hard-task -choices), the modified EEfRT (mean number of clicks) and follow-up questions concerning task strategy and motivation in Study 1 for different probabilities of reward attainment.
Table 8.
Zero-order correlations between the original EEfRT (percentage of hard-task -choices), the modified EEfRT (mean number of clicks) and follow-up questions concerning task strategy and motivation in Study 1 for different reward magnitudes.