Regions of decreased activity for hf-tRNS.

<p>Contrast <i>sham- Hfreq</i> (A) revealed changes in the left frontal cortex. Contrast <i>Lfreq-Hfreq</i> (B) revealed additional changes in right frontal cortex and precuneous.</p

Performance related decrease of brain activity during and after stimulation.

<p>Activity decreased with time for contrast <i>run1-run2</i> in the paracingulate gyrus, superior frontal gyrus, thalamus and hippocampus. (Z>3, P<0.05, corrected).</p

Changes in tracking error relative to the first trial.

<p>Shaded area corresponds to the stimulation period. Fifth Polynomial trendlines are superimposed on the data for easier visualization.</p

Peak voxel intensity and coordinates for brain regions showing performance-related activity.

<p>Peak voxel intensity and coordinates for brain regions showing performance-related activity.</p

Peak voxel intensity and coordinates for brain regions showing motor task-related activity.

<p>Peak voxel intensity and coordinates for brain regions showing motor task-related activity.</p

Motor task-related decrease of brain activity during and after stimulation.

<p>Activity decreased with time for contrasts <i>run1-run2</i> (A) in primary and premotor cortices, supplementary motor area (SMA), prefrontal cortex, occipital cortex, thalamus and basal ganglia and <i>run2-run3</i> (B) in the precuneous, superior parietal cortex, middle and inferior frontal gyrus, right prefrontal cortex, left inferior LOC and basal ganglia (Z>3, P<0.05, corrected).</p

The experimental procedure for the encoding A) and for the recognition B) phase of the verbal learning task.

<p>The experimental procedure for the encoding A) and for the recognition B) phase of the verbal learning task.</p

The summary of the fixed effects of the final model taking confidence rating as dependent variable (N = 7787; log-likelihood = 35888).

<p>Note: Random effect for subject intercept had SD of 12.49. SE: standard error of mean; df: degrees of freedom.</p><p>The summary of the fixed effects of the final model taking confidence rating as dependent variable (N = 7787; log-likelihood = 35888).</p

D’ values were significantly and marginally higher for the temporal and parietal groups respectively, compared with the sham stimulation group.

<p>D’ value is zero at random choice. Error bars represent standard error of the mean. Asterisk indicates significant differences; the plus sign indicates marginally significant differences.</p

The summary of the fixed effects of the final model taking accuracy as dependent variable (N = 8448; log-likelihood = -5269.6).

<p>Note: Random effect for subject intercept had SD of 0.16. SE: standard error of mean.</p><p>The summary of the fixed effects of the final model taking accuracy as dependent variable (N = 8448; log-likelihood = -5269.6).</p