The locus coeruleus norepinephrine (LC-NE) system regulates arousal and awakening; however, it remains unclear whether the LC does this in a global or circuit specific manner. We found partial anatomical segregation between the LC to pontine reticular nucleus (PRN) and LC to basal forebrain (BF) circuits. Extracellular NE dynamics in BF and PRN exhibited distinct […]
We reconsider sleep/wake brain states as being highly dynamic and regionally complex, rather than stationary and global. We review recent evidence for spatiotemporal complexity and advances in understanding the systems that regulate vigilance state, such as neuromodulatory systems – which may be more heterogenous than originally assumed. A modular and dynamic perspective highlights novel avenues […]
Sleep involves infra-slow ∼50-second fluctuations between disengagement and sensory reactivity. New findings reveal that the brain’s noradrenaline system controls these dynamics by acting in the thalamus to affect sleep spindles, and by modulating coordinated heart rate variations.
We studied the immediate effects of transient non-invasive transcutaneous vagal nerve stimulation (tVNS) on heathy naïve human participants using high density EEG and pupilometery. We found that tVNS induce transient pupil dilation as in in animal models, and attenuates EEG alpha oscillations anti correlated with arousal. Our results support the use of tVNS as non-invasive […]
A reduced responsiveness to external stimuli is the main characteristic of sleep. In this study we show that the LC, a small nucleus in the brainstem and the main source of noradrenaline, plays a central role in our ability to disconnect from the environment during sleep. We recorded rats cerebral cortical activity (Electroencephalogram; EEG) in […]
An identical sensory stimulus may or may not be incorporated into perceptual experience, depending on the behavioral and cognitive state of the organism. What determines whether a sensory stimulus will be perceived? Here we tested whether noradrenaline signaling may play a key role. We pharmacologically down- and upregulated noradrenaline signaling in healthy volunteers using clonidine […]
