Fig. 4: Effect of task difficulty and response deadline on the centro-parietal positivity (CPP).
From: Neural mechanisms of metacognitive improvement under speed pressure
a Grand average CPP waveform. Purple circles in the topographic map at stimulus-onset denote the electrode cluster used in the ERP analysis (i.e., Cz, CPz, Pz, CP1, CP2). The dashed vertical line in the stimulus-locked epoch denotes grand average response time. b Parameter estimates for the effect of Coherence on CPP amplitude. Negative values indicate reduced CPP amplitude on low relative to high coherence trials. Dashed vertical lines denote mean response times (low coherence: orange, high coherence: black). c Parameter estimates for the effect of Offset on CPP amplitude. Negative values indicate reduced CPP amplitude on small relative to large offset trials. Dashed vertical lines denote mean response times (small offset: indigo, large offset: green). d Parameter estimates for the effect of Deadline on CPP amplitude. Positive values indicate greater CPP amplitude on short relative to long deadline trials. Dashed vertical lines denote mean response times (short deadline: cyan, long deadline: purple). In all panels, black horizontal bars denote periods of statistical significance (p < 0.05, N = 40). All statistical tests were FDR corrected for multiple comparisons. Error bands denote standard error. Data were smoothed using a Gaussian window (SD = 16 ms) for visualisation only.
