Fig. 4.

Forest plot of tone duration discrimination studies showing the difference of MMN/LDN amplitude between the groups in μVs. The black square indicates the mean difference between the groups in each study (in μV; positive values indicate diminished MMN/LDN responses in SLI) and its size is scaled based on the effect size (a larger square for a bigger effect size). The dotted vertical line represents zero microvolt difference between the groups and horizontal lines at each square show associated confidence intervals (the arrow indicating that the line should continue). Black diamonds represent the results of the meta-analyses (random-effects model, RE) and their lateral tips show the corresponding confidence interval. F = frequency of tone stimuli, S = SOA, A = the mean age of participants in years, T = the mean time point of the analyzed MMN/LDN in ms, D = the difference between the standard and the deviant tones in absolute Hz, and RD = relative difference in percentage.