Meaningful novelty processing during sleep in humans
How does the sleeping brain process external stimuli, and in particular, up to which extent does it detect and process modifications in its sensory environment? In order to address this issue, we investigated brain reactivity to verbal and meaningful novel auditory stimuli during wakefulness and sleep in young healthy subjects. EEG (23 scalp electrodes referenced to nose), EOG and EMG were recorded during wakefulness and all-night sleep, while a passive oddball paradigm including standards, deviants and two types of novels was applied. Novel sounds were first names uttered by a neutral masculine voice: the subject’s own name (‘own’) and an unfamiliar first name (‘other’). They were presented rarely (p = 0.02) in a background of regularly presented tone-bursts. Stimuli were presented at a level of 50 dB SL via two mini-earphones inserted into the external acoustic canals. During wakefulness recordings, subjects watched a silent movie with subtitles. During sleep recordings, stimuli were presented continuously during the whole night. During wakefulness, ‘own’ and ‘other’ names evoked expected N1 and P3a components. Interestingly, the P3a component peaked significantly earlier (15 ms) for the ‘own’ name. In addition, analysis of the data revealed that the ‘own’ name only, evoked a large parietal positivity peaking at 550 msec. An enhanced response to the ‘own’ name was also detected during sleep, at late latencies, with a similar topography as the one observed during wakefulness (Figure), in sleep stages 2, 4 and REM (Rapid Eye Movement) sleep. These results demonstrate that, during wakefulness, the own first name induces an earlier reorientation of attention than another first-name, possibly due to its greater familiarity or to its meaning. The ‘own’ name subsequently evoked a late positivity which may be interpreted as a complex cognitive processing such as a recall of memory associated to the ‘own’ name. Only late positivities were found in sleep stages 2, 4 and REM suggesting that only the latter effect is preserved during sleep. In conclusion this study demonstrates verbal discrimination for the first time in all sleep stages and suggests a possible preservation of stimulus-driven recollection during sleep.
Conference:
10th International Conference on Cognitive Neuroscience, Bodrum, Türkiye, 1 Sep - 5 Sep, 2008.
Presentation Type:
Poster Presentation
Topic:
Perceptual Processing and Recognition
Citation:
Eichenlaub
J,
Ruby
P and
Morlet
D
(2008). Meaningful novelty processing during sleep in humans.
Conference Abstract:
10th International Conference on Cognitive Neuroscience.
doi: 10.3389/conf.neuro.09.2009.01.357
Copyright:
The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers.
They are made available through the Frontiers publishing platform as a service to conference organizers and presenters.
The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated.
Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed.
For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions.
Received:
15 Dec 2008;
Published Online:
15 Dec 2008.
*
Correspondence:
Jean-Baptiste Eichenlaub, INSERM U821, Lyon, France, jb.eichenlaub@gmail.com