Vowel coding relies on F0-synchronized rate contrasts, not just formant peaks.

Evidence

Vowel coding studies have historically focussed on representation of spectral peaks, or formants, in AN rates or synchrony to stimulus components near BF. These representations are vulnerable to additive noise and vary with sound level. The sensitivity of midbrain neurons to low-frequency fluctuations inspired a shift of focus to the contrast in pitch-related fluctuations along the BF axis in vowel coding (Carney et al. 2015 ). In the healthy AN, there is a robust contrast in the profile of the F0-synchronized discharge rate across the BF axis (Fig. 2d ). Midbrain neurons’ sensitivities to these F0-synchronized rates transforms the temporally coded AN profile into a discharge rate profile (Fig. 4a ). — Dijk, Pim van, Physiology, Psychoacoustics and…, 5509

Categorization

• DEFINE: Clarifies what F0-synchronized rate profile means versus formant-based representation in AN coding.
• XREF: connects to: Vowel identification depends on formant peaks being representable in the output spectrum. — David Howard, Jamie Angus, coustics and Psychoacoustics, 1368