In this study Christine Blume and Manuel Schabus and their colleagues sought to investigate to what extent processing of environmental stimuli is still possible during sleep and especially deep NREM and REM sleep. Moreover, they were interested in whether inhibition and thus sleep-protection by sleep-specific EEG phenomena (i.e. sleep spindles and slow oscillations) is an all-or-none phenomenon or whether inhibition is tuned to stimulus salience. They find that the brain is able to differentiate among paralinguistic aspects of a stimulus, that is between familiar and unfamiliar voices, in all sleep stages. Morever, results indicate that these phenomena attenuate stimulus processing, but their inhibitory sleep-protective function seems to be scaled to stimulus salience.
New Publication: “Standing Sentinel during Human Sleep: Continued Evaluation of Environmental Stimuli in the Absence of Consciousness” in NeuroImage