Slope reversals in the music and speech of tone and non-tone language speaking cultures.
(A) Box plot showing the distribution of the number of melodic slope reversals per melody in the tone (red) and non-tone (blue) language music databases (n1 = n2 = 90). Horizontal yellow lines indicate medians; colored boxes specify inter-quartile ranges and dashed lines the ranges without outliers. (B) Box plot of the number of prosodic slope reversals per speaker in the tone and non-tone language speech databases (n1 = n2 = 40). The cross indicates an outlier (defined as greater/lesser than 1.5x the inter-quartile range). (* = P<0.001; all comparisons were made using a Mann Whitney U-test, α = 0.05, two-tailed).