Isolating feedforward, lateral, and feedback mechanisms underlying perceptual and attentional impairments of conscious access

Abstract

AbstractThis study investigates failures in conscious access resulting from either weak sensory input (perceptual blindness) or unattended input (attentional blindness). Participants viewed an illusory Kanizsa triangle within a rapid serial visual presentation of distractor stimuli while electroencephalogram (EEG) was recorded. Distinct neural patterns associated with feedforward, lateral, and local versus global feedback processes were identified by training and testing classifiers on specific stimulus features. Perceptual performance was equated between the perceptual (masking) and attentional (attentional blink) manipulation to circumvent common confounds related to conditional differences in task performance. Decoding analyses revealed that lateral and local feedback processes were impaired by masking but spared by the attentional blink, with feedforward processing left largely unaffected by either manipulation. Global feedback processes were directly related to perceptual and metacognitive performance (conscious access), independent of the manipulation. These findings contribute to a comprehensive understanding of four distinct neural stages leading to conscious access.