Article Figures & Data
Figures
- Figure 1.
Experiment paradigm. In both the preparatory and the feedback stage, trial start was signaled by a white circle appearing on the screen. When a pedal press was executed, the circle turned red for 1 s. In the preparatory stage, the trial ended and a fixation cross was shown for an intertrial period of 3 s. In the feedback stage, before the trial ended a number was shown on the screen for 1.5 s, after which the fixation cross was shown.
- Figure 2.
Waveforms and topographies of RPs for different feedback levels. For each participant, trials were grouped into five quantiles depending on the feedback score that was calculated in real time, color coded in all panels from low (light) to high (dark). The left shows the grand average waveforms of RPs at channel Cz for the five quintiles, baseline corrected in the interval [−1000,−900] ms. SE is shown as a shaded area. The right shows the corresponding scalp topographies of the average voltage in the interval [−100,0] ms for the five quintiles.
- Figure 3.
Change of feedback scores and RP waveform in the course of the feedback stage. A, Gray dots show single-trial feedback scores, pooled across all participants, as a function of TN. Black circles and vertical lines show averages of individual participants and population medians, respectively, both calculated over consecutive, non-overlapping bins of 25 trials. B, Grand average RPs in channel Cz, computed for the first (blue) and the second (red) half of trials, respectively. SE is shown as a shaded area. Baseline correction was in the interval −1000 to −900.
- Figure 4.
Modulation of RPs by movement characteristics (channel Cz). We checked whether basic spontaneous movement characteristics included in the model as effects of no interest modulated the RP waveforms (as reported in previous literature). Top, Boxplots show, for each participant individually, the distribution of WT (A), MD (B), and PA (C) of movements executed. Bottom, For each participant individually, two average RPs were generated each using half of the trials (according to a median split of the corresponding measure, indicated in the color coded regions of the boxplots). The curves show grand averages across participants. Blue and red traces show the average RP for the shorter and longer half of WT (A), for the faster and slower half of movements (B), and for the smaller and larger half of PAs (C), respectively. SE is shown as a shaded area. Baseline correction was in the interval −1000 to −900. Gray bars indicate in which consecutive, non-overlapping 100-ms windows a paired t test showed a significant (p < 0.05) difference of RP averages. The small differences in the waveform in A did not affect the EEG classifier (and therefore the feedback scores), which takes into account the RP waveform across all selected channels.
- Figure 5.
Likert scale rating in questionnaire of subjective experience. Histograms show the number of participants rating question 1 (“Overall, how much did you feel you could influence the scores shown on screen?”) on a Likert scale from 1 (not at all) to 5 (a lot), and question 2 (“How hard/easy was it to find a strategy that had an effect on the scores?”) on a Likert scale from 1 (very hard) to 5 (very easy).
Extended Data
Extended Data Figure 1-1
Participants΄ self-reports on questionnaire about strategies. Download Figure 1-1, DOCX file.
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