Figure 1. Schematic spectrograms of the various perceptual tasks used in the study.

. (A) Fundamental frequency difference limens (F0 DLs). Participants were instructed to detect the interval containing the higher pitch. (B) Pitch speed. Following a brief warble tone (distracter) and period of silence, listeners heard two pure-tones and were asked to identify their direction (i.e., ascending or descending). Test tone duration was varied adaptively to measure listener’s temporal threshold for identifying directional changes in pitch. (C) Pitch memory ability was assessed based on how well listeners judged whether or not a single probe tone had been heard in a preceding four-note melody. (D) Melody discrimination was measured by assessing how well listeners could discriminate short melodies that differed by as little as ½ or ¼ semitone (grey oval).