Neurobiology of sleep

Question 1

What is the “sleep gate”?

Answer 1

The point when you fall asleep. There is a large difference between the homeostatic sleep drive and circadian drive for arousal.

Question 2

What is process S?

Answer 2

The accumulation of adenosine in the CNS

Question 3

What is process C?

Answer 3

The circadian drive of arousal, affected by blue light/melatonin and eating

Question 4

What does VLPO stand for/do?

Answer 4

Ventrolateral pre-optic nucleus. Sends GABAergic projections to all conciousness stimulating areas.

Question 5

How many times do we cycle between SWS and REM per night?

Answer 5

5-6

Question 6

What does REM help with?

Answer 6

dealing with emotions

Question 7

Which half of sleep is associated with more SWS?

Answer 7

First half. The depth and duration of SWS is important

Question 8

How does orexin increase the risk of AD?

Answer 8

Orexin prevents the brain from flushing away A-beta in the CSF. Older people –> reduced REM sleep –> less flushing of A-beta –> increased risk for AD.

Question 9

What is SWS important for?

Answer 9

consolidating memories.

Question 10

which stage is the largest proportion of sleep time?

Answer 10

2 - important for procedural memory (piano)

Question 11

What effects time in SWS?

Answer 11

Exercise increases time in SWS, depression reduces it.

Question 12

During what sleep stage is Ach concentration similar to that in wakefulness?

Answer 12

REM

Question 13

How do benzo’s work?

Answer 13

Bind the GABA receptor and improve its responsiveness to GABA. Not selective to VLPO neurons.

Question 14

What are some bad effects of benzo’s?

Answer 14

Day time sedation (whilst driving)
Decreased reaction time
Reduced SWS and REM sleep
Unsteadiness of gait
Risk of tolerance
Risk of withdrawal
Risk of abuse

Question 15

What does caffeine do?

Answer 15

Competes with adenosine, reduces depth of SWS in the first half of sleep