Sleep; Emotion; Perceptual Learning; Neural Plasticity; Functional MRI; EEG; Individual differences; Dreaming
Miendlarzewska E. A., Bavelier D., Schwartz S. (2016), Influence of reward motivation on human declarative memory, in
Neuroscience and biobehavioral reviews, 61, 156-76.
Igloi K., Gaggioni G., Sterpenich V., Schwartz S. (2015), A nap to recap or how reward regulates hippocampal-prefrontal memory networks during daytime sleep in humans, in
eLife, 4, 0.
Van Someren E. J., Cirelli C., Dijk D. J., Van Cauter E., Schwartz S., Chee M. W. (2015), Disrupted Sleep: From Molecules to Cognition, in
The Journal of neuroscience : the official journal of the Society for Neuroscience, 35, 13889-95.
Perogamvros L., Schwartz S. (2015), Dreaming, Neural Basis of, in Wright J. (ed.), 650-656.
Schwartz S., Perogamvros L. (2015), Emotion, Motivation, and Reward in Relation to Dreaming, in Kryger M. H. (ed.), 567-570.
Perogamvros L., Aberg K., Gex-Fabry M., Perrig S., Cloninger C. R., Schwartz S. (2015), Increased Reward-Related Behaviors during Sleep and Wakefulness in Sleepwalking and Idiopathic Nightmares, in
PloS one, 10, 0134504-0134504.
Perogamvros L., Schwartz S. (2015), Sleep and emotional functions, in
Current topics in behavioral neurosciences, 25, 411-31.
Sterpenich V., Piguet C., Desseilles M., Ceravolo L., Gschwind M., Van De Ville D., Vuilleumier P., Schwartz S. (2014), Sleep sharpens sensory stimulus coding in human visual cortex after fear conditioning, in
NeuroImage, 100, 608-18.
Schmidt R., Schwartz S. (2013), Le rêve, une forme de thérapie: Le retour du refoulé dans le rêve à la lumière de la recherche empirique, in
Psychoscope, 12, 12.
Rauss K., Schwartz S. (2012), Dissociating learning-induced changes in fMRI signal from structural modifications: a comment on Dorjee and Bowers (2012), in
Cortex; a journal devoted to the study of the nervous system and behavior, 48, 515.
Desseilles M., Mikolajczak M., Schwartz S. (2012), Sommeil, rêves et régulation des émotions, in Mikolajczak M. Desseilles M. (ed.), 87.
Perogamvros Lampros, Schwartz Sophie (2012), The roles of the reward system in sleep and dreaming., in
Neuroscience and biobehavioral reviews, 36(8), 1934-51.
Richiardi J., Eryilmaz H., Schwartz S., Vuilleumier P., Van De Ville D. (2011), Decoding brain states from fMRI connectivity graphs, in
NeuroImage, 56, 616-26.
Background: Recent data has accumulated to suggest that sleep boosts learning and underlying neural plasticity. Yet the factors that govern the selection of information to be further consolidated in sleep remain largely unknown. Here, we hypothesize that the affective relevance of a stimulus affects its subsequent reprocessing during sleep, at both the cognitive and neural levels. Specifically, the proposed experiments will test whether sleep and emotion interact to foster a shift in memory representations, and may thus influence subsequent decision making. Several lines of evidence suggest interactions between sleep and affective processes: a) sleep disorders are frequently associated with emotion disorders; b) limbic, mesolimbic, and ventral medial prefrontal regions, all involved in the processing of emotional relevance, are activated during human rapid eye movement sleep; c) consistent with an activation of emotion circuits during sleep, subjective experiences during sleep (i.e. dreams) can be highly emotional; d) waking neuronal activation associated with a rewarded task is replayed during sleep in hippocampus and ventral striatal regions in rodents. Furthermore, our recent fMRI work on narcoleptic patients shows that brain circuits involved in the stabilization of sleep-wake states (hypocretin/orexin system) exert a strong influence on emotional learning and reward-related responses in mesolimbic dopamine regions and in the amygdala. Together these findings provide new and converging support for substantial functional interactions between sleep and emotion brain circuits. We believe that this emerging view is promising both for fundamental research and for its implications for understanding diseases and promoting public health.Aims/hypotheses: Our main goal is to investigate the role of the affective significance of a stimulus on offline memory processes, particularly during sleep, both at the behavioral and neural levels in healthy adult humans. The following hypotheses are tested. a) The emotional value or relevance of a stimulus guides the selection of memories that will be subsequently consolidated. b) Sleep represents a permissive period for memory reprocessing and neural remodeling to occur. c) Sleep and emotion interact to induce changes in memory representations. d) The neural mechanisms underlying these effects involve influences of emotional circuits (limbic and mesolimbic networks) onto sensory and/or memory systems. e) The strength of the emotional effects on memory and neural responses varies across individuals and correlates with individual differences in emotions in dreams. Methods: To experimentally manipulate the emotional relevance of a stimulus, we use two paradigms that involve distinct brain structures: aversive conditioning (amygdala, insula) and reward learning (striatum, ventral tegmental area). To test for the effects of sleep on memory, we measure behavioral performance and whole-brain fMRI activity after a delay that includes sleep or not. With simultaneous EEG and fMRI, we directly assess changes in neural activity and connectivity during sleep after emotional learning, and use dedicated methods to detect any reactivation of patterns of brain activity corresponding to emotionally-relevant material. Correlations with individual dream data are performed.Potential value of the project: The project addresses fundamental and timely questions about the role of sleep in cognitive and affective processes. It involves innovative cognitive tasks, a unique combination of methodological approaches, as well as outstanding technical facilities and scientific expertise, which together guarantee the success of this ambitious project. The expected results (based on our preliminary findings) will establish emotional relevance as a key component of sleep-related memory consolidation and dreaming. It will also show that specific neural mechanisms mediate these emotional effects on brain plasticity, therefore clarifying the physiological links between the regulation of sleep-wake states and affective processes that serve the optimization of waking behavior. Because sleep disturbances constitute a major and pervasive health problem, our results are also expected to substantially improve awareness about the important socioeconomical consequences of sleep curtailment on education and well-being.