Parameters and their changes applied to the base sentences for the preparation of the stimuli.

A formant shift ratio greater than 1 increases the frequency of all formants (A ratio of 1.1 simulates a shortening of the vocal tract by approximately 10%, and a ratio of 0.9 a lengthening by 10%.). Pitch shift modifies the median pitch of an entire sound. Final F0 slope modifies the pitch slope of the final syllable in “exam” in Experiment 1. Pitch range expands or compresses the dynamic F0 range of the entire sentence. The columns are independent of each other.