The best interaural phase deviation for evoking neural responses depends on modulation rate

Evidence

Evoked responses to the intermediate IPM rate (6.8 Hz; Fig. 2 ) became steady state at the same rate as the IPM, and so we term this response the IPM-FR. … Responses obtained at 6.8 Hz IPM rate were maximal for IPDs spanning ±45–±90°, whereas responses obtained at 13.4 Hz IPM rate increased monotonically with increasing IPD. — Dijk, Pim van, Physiology, Psychoacoustics and…, 2949

Finally, we assessed the frequency bin corresponding to the IPM rate. A three-way non-parametric repeated measures ANOVA with factors of electrode position (left or right mastoid), IPM rate, and IPD revealed that factors IPM rate (p < 0.001), IPD (p < 0.001) as well as the interaction between IPM rate and IPD (p = 0.01) were significant. Responses obtained at 6.8 Hz IPM rate were maximal for IPDs spanning ±45–±90°, whereas responses obtained at 13.4 Hz IPM rate increased monotonically with increasing IPD. — Dijk, Pim van, Physiology, Psychoacoustics and…, 2977

A three-way non-parametric repeated measures ANOVA with factors of electrode position (left or right mastoid), IPM rate, and IPD revealed that factors IPM rate (p < 0.001), IPD (p < 0.001) as well as the interaction between IPM rate and IPD (p = 0.01) were significant. Responses obtained at 6.8 Hz IPM rate were maximal for IPDs spanning ±45–±90°, whereas responses obtained at 13.4 Hz IPM rate increased monotonically with increasing IPD. — Dijk, Pim van, Physiology, Psychoacoustics and…, 2965

This is confirmed by comparing the variability of the individual responses in the time domain as well as the frequency domain (Fig. 2 ), where the spectral magnitude was almost twice larger than that the largest magnitude obtained at the lowest IPM rate. Moreover, the average spectral magnitude of the next harmonics was almost twice smaller than those obtained at the lowest IPM rate. — Dijk, Pim van, Physiology, Psychoacoustics and…, 2964

As diotic carrier phase modulation did not elicit detectable neural responses, the observed responses to IPM must reflect binaural processing rather than the monaural encoding of abrupt phase shifts (Ross et al. — Dijk, Pim van, Physiology, Psychoacoustics and…, 2985

We have demonstrated that an IPM-FR can be reliably obtained and used as an objective measure of binaural processing. Depending on the IPM rate, periodic IPMs can evoke a robust steady-state following response. — Dijk, Pim van, Physiology, Psychoacoustics and…, 2985

Categorization

• corroborated: 7 independent passages support this claim — Dijk, Pim van, Physiology, Psychoacoustics and…, 2949; Dijk, Pim van, Physiology, Psychoacoustics and…, 2977; Dijk, Pim van, Physiology, Psychoacoustics and…, 2965 (+2 more)
• XREF: connects to: Low- and high-frequency binaural brainstem pathways prefer opposite interaural phase ranges; Slow interaural-phase modulation evokes transient P1-N1-P2 waves while faster rates produce steadier following responses; Binaural envelope-delay sensitivity drops once tone separation exceeds the critical band. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 911 (+1 more)

Broader Connections

• Binaural envelope-delay sensitivity drops once tone separation exceeds the critical band. #expands (0.85) — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 911