Sleep to remember and sleep to forget: sleep, memory and adult hippocampal neurogenesis Flashcards
What is narcolepsy?
Narcolepsy is a chronic sleep disorder characterized by overwhelming daytime drowsiness and sudden attacks of sleep.
What are the 2 stages of sleep?
Sleep is divided into stages of non-REM and REM sleep
How cyrcadian rhytm is maintained?
By environmental cues like light/dark. But they do not depend on the environmental cues as they are generated internally. Circadian rhythms can persist in the absence of environmental cues. Circadian rhythms are endogenous (having an internal cause or origin). Circadian rhythms are established by the SCN (suprachiasmatic nucleus).
What are the 3 main features (behaviours/location) of the suprachiasmatic nucleus (SCN)?
What photoreceptors are?
Cells that are responsible for the transduction (conversion) of light (cones and rods).
What is melanopsin?
The explanation for this is in the group of retinal ganglion cells, expressing a photopigment called melanopsin, that emits information to the suprachiasmatic nucleus. The melanopsin is light-sensitive at the wavelength of the blue colour.
Melanopsin expressing retinal ganglion cells represents a third class of ocular photoreceptors and is involved in irradiance detection and non-image-forming responses to light including pupil constriction, circadian entrainment, and regulation of sleep
What pathways keep us awake (2)?
Ascending projection system From neurons in the brainstem up towards and terminating in the cortex:
- One pathway comes mainly from cholinergic neurons in the pedunculopontine and laterodorsal tegmental nuclei primarily innervating the thalamus.
- The second pathway has monoaminergic neurons containing serotonin, noradrenaline, glutamate, dopamine, and histamine as neurotransmitters. This pathway comes from neurons in the locus coeruleus, dorsal and median raphe nuclei, parabrachial nucleus, periaqueductal grey matter, and tuberomammillary nucleus. Differentially, the monoaminergic pathway does not go to the thalamus.
Differences and similarities between cholinergic and aminergic projections (3)?
What system is responsible for wakefulness?
Ascending projection system. (That has 2 pathways: cholinergic, aminergic)
The ARAS functions to arouse the cerebral cortex, to awaken the brain to a conscious level, and to prepare the cortex to receive the rostrally projecting impulses from any sensory modality.
What is orexin?
A neuropeptide in the lateral hypothalamus is also known as hypocretin. A person who has lost orexin neurons is sleepy during the day and falls asleep easily in the absence of stimulation.
What substance accumulates during the wakefulness?
Adenosine is a chemical found in human cells. There are three different forms: adenosine, adenosine monophosphate (AMP), and adenosine triphosphate (ATP).
How sleep and immune systems are related?
Sleep disturbance results in hormone activation of glucocorticoid receptors in leukocytes, which leads to profound suppression of antiviral gene programs. Sleep disturbance also activates the release of neurotransmitter, norepinephrine into primary and secondary lymphoid organs, all other major organ systems includes vasculature and perivascular tissue as well as many other peripheral tissues. The suppression of adaptive immune response is thought to contribute to increased susceptibility to infectious disease and decreased response to vaccines
How sleep deprivation impacts gene expression?
Within specific genomic regions and throughout the genome, changes in DNA methylation and hydroxymethylation can be seen following sleep deprivation. These changes correlate with altered gene expression and help identify pathways dysregulated by sleep loss.
What is cAMP-PKA pathway?
What is the cAMP signaling pathway?
In the field of molecular biology, the cAMP signaling pathway, also known as the adenylyl cyclase pathway, is a G protein-coupled receptor-triggered signaling cascade used in cell communication.
