Do Zwicker Tones Evoke a Musical Pitch?

Area of Science:

• Auditory Neuroscience
• Psychoacoustics
• Music Perception

Background:

• The perception of musical pitch is traditionally linked to phase locking in the auditory nerve.
• Zwicker tones (ZTs) are tonal percepts arising from notched noise, with pitch in the notch frequency range.
• Evidence suggests ZTs may not involve mechanical production in the cochlea, questioning peripheral phase locking.

Purpose of the Study:

• To determine if musical pitch can be perceived in the absence of peripheral phase locking.
• To investigate the role of the auditory periphery in pitch perception using Zwicker tones.
• To compare pitch perception of Zwicker tones with that of pure sinusoids.

Main Methods:

• Musically trained subjects performed two experimental stages involving Zwicker tones and sinusoids.
• Stage I: Subjects matched decaying sinusoids to perceived Zwicker tones by adjusting frequency, level, and decay time.
• Stage II: Subjects set a sinusoidal pitch at a specific musical interval below a Zwicker tone or a reference sinusoid.

Main Results:

• Subjects could set frequency ratios for Zwicker tones, indicating pitch perception.
• Adjustment variability was higher for Zwicker tones (1.1-2.2 times) compared to equally salient sinusoids.
• Appropriate frequency ratios were selected, supporting the existence of pitch for ZTs.

Conclusions:

• Musical pitch perception may not strictly require peripheral phase locking.
• Zwicker tones provide a paradigm for studying pitch perception independent of peripheral mechanisms.
• The findings challenge the necessity of phase locking for the perception of musical pitch.