Search results
Results From The WOW.Com Content Network
Sleep onset is the transition from wakefulness into sleep. Sleep onset usually transits into non-rapid eye movement sleep (NREM sleep) but under certain circumstances (e.g. narcolepsy) it is possible to transit from wakefulness directly into rapid eye movement sleep (REM sleep).
Orexin neurons play a crucial role in promoting wakefulness and regulating arousal states. Modafinil may increase signaling within hypothalamic orexin pathways, potentially contributing to its wake-promoting effects.
[1] [24] [25] Orexin neurons in the posterior lateral hypothalamus potentiate neurons in the ascending arousal system and help stabilize the brain in the waking state (and consolidated wakefulness, which builds up homeostatic sleep drive, helps stabilize the brain during later sleep). The loss of orexin neurons in the disorder narcolepsy ...
Two other neurotransmitters, orexin and gamma-Aminobutyric acid (GABA), seem to promote wakefulness, diminish during deep sleep, and inhibit paradoxical sleep. [ 2 ] [ 25 ] Unlike the abrupt transitions in electrical patterns, the chemical changes in the brain show continuous periodic oscillation.
We haven't published our data concerning arousal per se (it's not what we were studying), so all I have is my word, but mice are very much aroused beyond simple wakefulness upon central delivery of orexin-A. (Wang et al have reported increased spopntaneous activity in orexin-A-treated rats with free access to running wheels.)
See Lateral hypothalamus § Function – primary source of orexin neurons that project throughout the brain and spinal cord Tuberomammillary nucleus [17] arousal (wakefulness and attention) feeding and energy balance; learning; memory; sleep
The endogenous orexin neuropeptides, orexin A and orexin B, are involved in the regulation of sleep–wake cycles and act to promote wakefulness. [34] [16] [7] Deficiency of orexin signaling is thought to be the primary cause of the sleep disorder narcolepsy. [34] [16] Disturbances in orexin signaling may also be involved in insomnia. [34]
A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a synapse.The cell receiving the signal, or target cell, may be another neuron, but could also be a gland or muscle cell.