Auditory nerve phase locking degrades above 1500 Hz and is weak above 4 kHz

Evidence

In some cases the neurons synchronize the firing with a certain phase of a periodic signal, a phenomenon called phase locking. … In humans the synchronization clearly occurs at frequencies below 1500 Hz, degrades at frequencies above it, and is weak above 4 kHz. For such continuous signals, it is mainly the place and average rate that are mediated above this frequency, not the temporal details. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 793

In some cases the neurons synchronize the firing with a certain phase of a periodic signal, a phenomenon called phase locking. This was observed in an experiment where the neurophysiological response from the auditory nerve of a cat to a periodic excitation was recorded, and the data were presented as a stimulus level versus synchronous firing rate plot, as shown in Figure 7.18 for different frequencies of a sinusoidal signal. The neural activity waveform is approximately a half-wave rectified (limited to positive values) form of the excitation waveform. In humans the synchronization clearly occurs at frequencies below 1500 Hz, degrades at frequencies above it, and is weak above 4 kHz. For such continuous signals, it is mainly the place and average rate that are mediated above this frequency, not the temporal details. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 793

Categorization

• DEFINE: Clearly defines phase locking as neurons syncing firing to a periodic signal’s phase.
• XREF: Explains the perceptual basis for why pitch and temporal fine structure matter mainly below ~1.5 kHz, relevant to audio coding (e.g., MP3 high-frequency processing) and psychoacoustics.
• corroborated: 3 independent passages support this claim — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 793