Is auditory awareness graded or dichotomous: Electrophysiological correlates of consciousness at different depths of stimulus processing.
Consciousness and Cognition June 19, 2024 Dmitri Filimonov, Sampo Tanskanen, Antti Revonsuo et al.
The level-of-processing (LoP) hypothesis, which describes how awareness of visual stimuli can be either gradual or all-or-none depending on feature depth, was tested in hearing for the first time. Participants heard words from different categories spoken in different pitches near the perceptual threshold. Results indicate that LoP also applies to the auditory modality. The auditory awareness negativity (AAN) was an early correlate of awareness independent of LoP, while late positivity (LP) was modulated by awareness, performance accuracy, and level of processing.