One second of exposure triggers neural spectral adaptation in hearing

Evidence

The ability to do this is most probably a result of neural processes within the hearing system. For example, a study by Summerfield et al. (1984) shows that exposure for just 1 second to a sound can result in spectral adaptation, possibly via neural adaptation in the auditory periphery. Summerfield et al. (1984) played a sequence of sounds to the listener the first of which consisted of a harmonic complex containing the first 50 harmonics of a tone, with a number of those 50 harmonics reduced in amplitude. The complex was then heard again but with the harmonics which had previously been reduced in level increased to the level of the remaining harmonics. When listening to the second sound, the components that had changed in level were heard to stand out perceptually from the rest of the tone. This enhancement effect appears to demonstrate the auditory system’s heightened sensitivity to temporal changes in spectrum and may show a mechanism which helps listeners to perceive differences in magnitude spectra between different sounds, as well as a system that can remove spectral distortion. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1252

Categorization

• QUESTION: The enhancement effect (contrast enhancement after adaptation) seems behaviorally similar to visual afterimages - worth checking whether a shared neural gain-normalization mechanism operates across modalities.
• corroborated: 2 independent passages support this claim — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1252
• XREF: connects to: Brain efferents can dynamically adjust cochlear gain during listening; Brief low-frequency tones can temporarily boost then depress hearing thresholds; Reversible threshold shifts after noise exposure mask ongoing neural degeneration (+2 more)

Broader Connections

• Brief low-frequency tones can temporarily boost then depress hearing thresholds #corroborates (0.75)
• Brain efferents can dynamically adjust cochlear gain during listening #expands (0.72)
• Reversible threshold shifts after noise exposure mask ongoing neural degeneration #qualifies (0.72)