Sensory and Perceptual Decisional Processes Underlying the Perception of Reverberant Auditory Environments.

Area of Science:

• Neuroscience
• Auditory Perception
• Acoustics

Background:

• Reverberation is key to understanding acoustic environments but how the brain represents it is unclear.
• Existing research focuses on sound source representation, not environmental acoustics.
• Human listeners use reverberation for orientation and perception.

Purpose of the Study:

• To characterize neural responses to varying levels of environmental reverberation realism.
• To investigate how the brain distinguishes real-world reverberation from synthetic reverberation.
• To identify neural stages involved in processing natural acoustic environments.

Main Methods:

• Multivariate pattern analysis applied to electroencephalographic (EEG) brain signals.
• Participants listened to speech samples convolved with real and synthetic reverberant impulse responses.
• Listeners judged the realism of the reverberant environments.

Main Results:

• Participants distinguished real from synthetic reverberation with ~75% accuracy.
• EEG decoding revealed a multistage process with early (temporal) and late (centroparietal) components.
• Distinct neural stages likely reflect sensory encoding and perceptual decision-making.

Conclusions:

• Reverberation carries significant environmental information, not just noise.
• The auditory system represents natural acoustic environments through distinct neural stages.
• Findings have applications in assistive navigation and enhancing virtual reality realism.