SLEEP Flashcards
What is sleep?
Readliy reversible state of reduced responisveness to, and interaction with the environment.
Why do we sleep?
- Energy conservation in period were we are not optimally adapted.
- Restoration
- Getting rid of brain waste from metabolism
- Restore glycogen levels
Give five sleep promoting factors.
- Melatonin –> Promotes sleep
- Adenosine –> Promotes sleep
- Nitric oxide –> Triggers adenosine
- Hypocreting –> Promotes wakefullness
- IL1 –> Promotes NREM
In what sleep stage does sleepwalking mostly occur?
In stage 4 Non-REM. It is difficult to awaken sleepwalkers as they are in deep slow-wave sleep.
When does sleep paralysis occur?
REM sleep.
Which four cortical regions are activated during REM sleep?
Anterior cingulate cortex, amygdala, parahippocampal gyrus, and pontine tegmentum.
Which cortical regions are inactivated during REM sleep?
Dorsolateral prefrontal cortex and the posterior cingulate cortex.
Which neurons are involved in sleep paralysis?
The inhibition of dorsal column nuclei results in diminished somatosensory stimuli. The inhibition of lower motorneurons results in paralysis.
How do the saccade-like eye movements in REM sleep arise?
In absence of external stimuli, endogenously generated signals are transmitted to the rostral interstitial nucleus which coordinates timing and direction of eye movement.
Why are dreams often emotional and contain inappropriate social characteristics?
The increase in limbic system, coupled with the decrease in the fronal cortex during REM sleep.
What characterizes Non-REM sleep stage 2?
Sleep spingles, these are periodic bursts of activity at about 10-12 Hz that last about 1-2 seconds. Arise as a result of interactions between thalamic and cortical neurons.
