Dissociating neural correlates of consciousness and task relevance during auditory processing

Area of Science:

• Neuroscience
• Cognitive Science
• Psychology

Background:

• Neural correlates of consciousness (NCC) research often uses event-related potentials (ERPs).
• Previous studies in visual modality suggest awareness reporting may confound neural correlates of consciousness.
• The auditory modality's constraints on NCC are not well understood.

Purpose of the Study:

• To investigate whether awareness reporting confounds NCC in the auditory modality.
• To identify specific electrophysiological markers of auditory awareness.
• To test the hypothesis that early sensory processing is crucial for conscious perception.

Main Methods:

• A sustained inattentional deafness paradigm was employed with spoken words.
• Electrophysiological responses (ERPs) were recorded under three conditions: uninformed/informed (U/I), informed (I), and task-relevant (TR).
• Participants' awareness was assessed via self-report after each condition.

Main Results:

• Awareness of spoken words was only reported by informed participants in the U/I condition.
• An anterior auditory awareness negativity (AAN) was associated with awareness in both U/I and I conditions.
• Late positivities in ERPs emerged only when speech stimuli were task-relevant (TR condition).

Conclusions:

• Early negativities, specifically AAN, index auditory awareness, similar to findings in other sensory modalities.
• Late positivities do not appear to be necessary for basic awareness but may relate to further processing.
• These findings support a recurrent processing framework emphasizing early sensory processing in conscious perception.