Perceptual asymmetries associated with changing-loudness aftereffects

Area of Science:

• Auditory perception
• Psychoacoustics
• Sensory neuroscience

Background:

• Auditory adaptation can lead to loudness aftereffects.
• Listening to sounds with changing levels can induce aftereffects where perceived loudness is altered.
• An asymmetry in these aftereffects has been observed, but its cause is debated.

Purpose of the Study:

• To investigate the asymmetry in loudness aftereffects.
• To determine if the "growing-louder effect" contributes to this asymmetry.
• To explore the potential ecological relevance of the observed aftereffect asymmetry.

Main Methods:

• Participants listened to sounds with increasing or decreasing sound levels.
• Loudness aftereffects were measured by nulling them with short test stimuli.
• The influence of the "growing-louder effect" was assessed by varying test stimulus duration.

Main Results:

• Increasing-loudness aftereffects were found to be greater than decreasing-loudness aftereffects.
• This asymmetry persisted even when the "growing-louder effect" was absent in longer test stimuli.
• The aftereffect asymmetry was independent of the "growing-louder effect".

Conclusions:

• A genuine perceptual asymmetry exists in loudness aftereffects.
• This asymmetry is not an artifact of the "growing-louder effect".
• The findings align with theories related to potential collision detection and visual motion aftereffects.