Information-Theoretic Approaches in EEG Correlates of Auditory Perceptual Awareness under Informational Masking

SIMPLE SUMMARY: Characterizing the brain activity related to the conscious perceptive experience is an important step toward understanding the relationship between brain activity and consciousness. In this study, we use an experimental protocol, where a human subject detects an auditory target embedded in a multitone masker. Since the subject can miss some targets, this experimental protocol provides trials where the target is present and perceived and some trials where it is present but not perceived. Comparing the difference in brain activity between these two conditions allows us to characterize specific patterns of brain activity related to auditory perceptual awareness. Here, we provide extensive characterization of the neural correlates of auditory perceptual awareness using information-theoretic approaches in brain electrical activity together with a more conventional analysis of brain signals. Among the information measures, integrated information measures are related to a specific theory of consciousness. We show that auditory perceptual awareness is associated with an enhancement in the informational content of the neural signals in fronto-central brain areas and with an increase in the redundancy of the information in the temporal cortices. These results thus characterize conscious perceptual states on the basis of the informational content of neural signals. ABSTRACT: In informational masking paradigms, the successful segregation between the target and masker creates auditory perceptual awareness. The dynamics of the build-up of auditory perception is based on a set of interactions between bottom–up and top–down processes that generate neuronal modifications within the brain network activity. These neural changes are studied here using event-related potentials (ERPs), entropy, and integrated information, leading to several measures applied to electroencephalogram signals. The main findings show that the auditory perceptual awareness stimulated functional activation in the fronto-temporo-parietal brain network through (i) negative temporal and positive centro-parietal ERP components; (ii) an enhanced processing of multi-information in the temporal cortex; and (iii) an increase in informational content in the fronto-central cortex. These different results provide information-based experimental evidence about the functional activation of the fronto-temporo-parietal brain network during auditory perceptual awareness.