Lecture 11: Sleep Neurobiology

Question 1

Which 4 parts of brain involved in maintaining wakefulness?

Answer 1

1. thalamus
2. hypothalamus
3. basal forebrain
4. cortex

Question 2

What is the role of orexin/hypocretin cells in the lateral hypothalamus?

Answer 2

Excitatory influence over system; controller of wakefulness

Question 3

What is the role of the ventrolateral pre-optic nucleus?

Answer 3

Inhibit nuclei in wakefulness system.

Active during sleep only/ Lesions reduce sleep.

Question 4

What are 2 REM sleep-on neurons and what are their function?

Answer 4

1. GABAergic neurons in sublateral dorsal regions of pons - inhibit REM-off neurons
2. cholinergic cells in LDT/PPT - act as switch; active during REM, no during non-REM; stimulate other pontine structures responsible for REM

Question 5

What are 2 REM sleep-off neurons and what are their functions?

Answer 5

1. vlPAG/LPT GABAergic neurons - inhibit REM and SLD

2. LC and raphe activate; inhibited by extended VLPO neurons

Question 6

What is the role of orexin in REM sleep control?

Answer 6

1. stimulates arousal system; inhibits VLPO

2. associated stimulaion of LC and raphe inhibits REM