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Objective: It has been reported that sleep deprivation affects the neurophysiological mechanisms underpinning the vigilance. Here, we tested the following hypotheses in the PharmaCog project (www.pharmacog.org): (i) sleep deprivation may alter posterior cortical delta and alpha sources of resting state eyes-closed electroencephalographic (rsEEG) rhythms in healthy young adults; (ii) after the sleep deprivation, a vigilance enhancer may recover those rsEEG source markers., Methods: rsEEG data were recorded in 36 healthy young adults before (Pre-sleep deprivation) and after (Post-sleep deprivation) one night of sleep deprivation. In the Post-sleep deprivation, these data were collected after a single dose of PLACEBO or MODAFINIL. rsEEG cortical sources were estimated by eLORETA freeware., Results: In the PLACEBO condition, the sleep deprivation induced an increase and a decrease in posterior delta (2-4 Hz) and alpha (8-13 Hz) source activities, respectively. In the MODAFINIL condition, the vigilance enhancer partially recovered those source activities., Conclusions: The present results suggest that posterior delta and alpha source activities may be both related to the regulation of human brain arousal and vigilance in quiet wakefulness., Significance: Future research in healthy young adults may use this methodology to preselect new symptomatic drug candidates designed to normalize brain arousal and vigilance in seniors with dementia., (Copyright © 2019 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Objective: To identify possible electroencephalographic (EEG) markers of donepezil's effect on cortical activity in young, healthy adult volunteers at the group level., Methods: Thirty subjects were administered a daily dose of either 5mg donepezil or placebo for 15days in a double-blind, randomized, cross-over trial. The electroencephalogram during an auditory oddball paradigm was recorded from 58 scalp electrodes. Current source density (CSD) transformations were applied to EEG epochs. The event-related potential (ERP), inter-trial coherence (ITC: the phase consistency of the EEG spectrum) and event-related spectral perturbation (ERSP: the EEG power spectrum relative to the baseline) were calculated for the target (oddball) stimuli., Results: The donepezil and placebo conditions differed in terms of the changes in delta/theta/alpha/beta ITC and ERSP in various regions of the scalp (especially the frontal electrodes) but not in terms of latency and amplitude of the P300-ERP component., Conclusion: Our results suggest that ITC and ERSP analyses can provide EEG markers of donepezil's effects in young, healthy, adult volunteers at a group level., Significance: Novel EEG markers could be useful to assess the therapeutic potential of drug candidates in Alzheimer's disease in healthy volunteers prior to the initiation of Phase II/III clinical studies in patients., (Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Auditory alarm misperception is one of the critical events that lead aircraft pilots to an erroneous flying decision. The rarity of these alarms associated with their possible unreliability may play a role in this misperception. In order to investigate this hypothesis, we manipulated both audiovisual conflict and sound rarity in a simplified landing task. Behavioral data and event related potentials (ERPs) of thirteen healthy participants were analyzed. We found that the presentation of a rare auditory signal (i.e., an alarm), incongruent with visual information, led to a smaller amplitude of the auditory N100 (i.e., less negative) compared to the condition in which both signals were congruent. Moreover, the incongruity between the visual information and the rare sound did not significantly affect reaction times, suggesting that the rare sound was neglected. We propose that the lower N100 amplitude reflects an early visual-to-auditory gating that depends on the rarity of the sound. In complex aircraft environments, this early effect might be partly responsible for auditory alarm insensitivity. Our results provide a new basis for future aeronautic studies and the development of countermeasures., (Copyright © 2013 Elsevier B.V. All rights reserved.)