Fig. 8. Key characteristics of human pitch behavior only emerge in noisy training conditions.

a Average power spectrum of training stimuli. Networks were trained on speech and music stimuli embedded in three different levels of background noise: high (column 1), low (column 2), and none (column 3). b Effect of training set noise level on network behavior in all five main psychophysical experiments (see Fig. 2a–e): F0 discrimination as a function of harmonic number and phase (row 1), pitch estimation of alternating-phase stimuli (row 2), pitch estimation of frequency-shifted complexes (row 3), pitch estimation of complexes with individually mistuned harmonics (row 4), and frequency discrimination with pure and transposed tones (row 5). Lines plot means across the ten networks; error bars indicate 95% confidence intervals bootstrapped across the ten networks.