The brain continuously integrates information from the external environment (exteroception) and the internal bodily milieu (interoception). However, how the balance between these two processing streams shifts across vigilance states with differing levels of environmental responsiveness remains poorly understood. Here, we examined neural responses to external auditory and internal cardiac...
Abstract The brain continuously integrates information from the external environment (exteroception) and the internal bodily milieu (interoception). How the balance between these two processing streams shifts across vigilance states with differing levels of environmental responsiveness, however, remains poorly understood. Here, we examined neural responses to external auditory and internal...
The function of dreams is a longstanding scientific research question. Simulation theories of dream function, which are based on the premise that dreams represent evolutionary past selective pressures and fitness improvement through modified states of consciousness, have yet to be tested in cross-cultural populations that include small-scale forager societies. Here, we analyze dream content...
Nightmare disorder (ND) is characterized by dreams with strong negative emotions occurring during rapid eye movement (REM) sleep. ND is mainly treated by imagery rehearsal therapy (IRT), where the patients are asked to change the negative story line of their nightmare to a more positive one. We here used targeted memory reactivation (TMR) during REM sleep to strengthen IRT-related memories and...
The waking brain efficiently detects emotional signals to promote survival. However, emotion detection during sleep is poorly understood and may be influenced by individual sleep characteristics or neural reactivity. Notably, dream recall frequency has been associated with stimulus reactivity during sleep, with enhanced stimulus-driven responses in high vs. low recallers. Using...
Summary: Functional dissociations in the brain observed during non-rapid eye movement (NREM) sleep have been associated with reduced information integration and impaired consciousness that accompany increasing sleep depth. Here, we explored the dynamical properties of large-scale functional brain networks derived from transient brain activity using functional magnetic resonance imaging. Spatial...
Nightmares are characterized by the experience of strong negative emotions occurring mainly during REM sleep. Some people suffer from nightmare disorder, which is defined by the repeated occurrence of nightmares and by significant distress in wakefulness. Yet, whether frequent nightmares relate to a general increase in emotional reactivity or arousal during sleep remains unclear. To address...
Ketamine has been documented for its rapid antidepressant effects. However, optimal dose and delivery route have not yet been thoroughly investigated. The objectives of this study were to document the safety and test the antidepressant and antisuicidal effects of a single rapid 1-minute injection of ketamine 0.5 mg/kg in treatment-resistant depression (TRD). Ten patients with TRD were included...
The mirror-gazing task (MGT) experimentally induces illusions, ranging from simple color changes in the specular image of oneself, to depersonalization-like anomalous self-experiences (ASE) as in experiencing one's specular image as someone else. The objective was to characterize how connectivity in resting-state networks (RSNs) differed in adolescents reporting such depersonalization-like ASEs...
INTRODUCTION: Functional magnetic resonance imaging studies enable the investigation of neural correlates underlying behavioral performance. We investigate the effect of active and sham Continuous Positive Airway Pressure (CPAP) treatment on working memory function of patients with Obstructive Sleep Apnea Syndrome (OSAS) considering Task Positive and Default Mode networks (TPN and DMN)....
BACKGROUND: We previously suggested that abnormal sleep behaviors, i.e., as found in parasomnias, may often be the expression of increased activity of the reward system during sleep. Because nightmares and sleepwalking predominate during REM and NREM sleep respectively, we tested here whether exploratory excitability, a waking personality trait reflecting high activity within the mesolimbic...
Recent studies in sleep and dreaming have described an activation of emotional and reward systems, as well as the processing of internal information during these states. Specifically, increased activity in the amygdala and across mesolimbic dopaminergic regions during REM sleep is likely to promote the consolidation of memory traces with high emotional/motivational value. Moreover, coordinated...
To test whether mental activities collected from non-REM sleep are influenced by REM sleep, we suppressed REM sleep using clomipramine 50mg (an antidepressant) or placebo in the evening, in a double blind cross-over design, in 11 healthy young men. Subjects were awakened every hour and asked about their mental activity. The marked (81%, range 39-98%) REM-sleep suppression induced by...
Dream is a state of consciousness characterized by internally-generated sensory, cognitive and emotional experiences occurring during sleep. Dream reports tend to be particularly abundant, with complex, emotional, and perceptually vivid experiences after awakenings from rapid eye movement (REM) sleep. This is why our current knowledge of the cerebral correlates of dreaming, mainly derives from...
WHAT GOES THROUGH OUR MINDS WHILE WE FALL ASLEEP? AT SLEEP ONSET, STUDENTS PREPARING FOR EXAMS COMMONLY RE-EXPERIENCE SOME OF the material they have been revising during the day; lovers have pervasive thoughts about their romantic partner; software developers may see bits of programming codes unfold in their mind's eye. These anecdotal observations suggest that, during the transition from...
Our neurobiological knowledge about human dream organisation results primarily from the study of Rapid-Eye-Movement (REM) sleep.In humans, functional neuroimaging techniques, using H 2 15 O or 18 FDG positron emission tomography (PET) and functional magnetic resonance imaging (fMRI), allowed the mapping of the regional cerebral activity during this sleep stage, which is dominated by the...
New phenomenological data demonstrate that integrated life episodes are incorporated in no more than 1-2% of dream reports. This appears to be at odds with the replay of temporally sequenced memory at the level of neuronal ensembles observed in some animals during sleep. This result will constrain emerging ideas on memory reactivation during sleep and the role of sleep in memory consolidation.
Contemporary cognitive and neuropsychological approaches to dreaming show striking methodological and conceptual similarities with the scientific dream literature of the last century. The use of introspective dream reports and the emphasis on dream phenomenology are characteristic of both periods but were bannished during the first half of this century, the former by behaviorism, the latter by...