3. theories on function of sleep

Question 1

functions of sleep consist of:

Answer 1

1. a core function -> explaining evolution of sleep
2. associated functions -> explaining the many features

Question 2

2-process model of sleep regulation is:

Answer 2

1. circadian rhythm (because of diurnal variation in light/dark/temp./etc.
2. homeostatic drive (neuronal assemblies start to oscillate in up- and down states which develops to sleep)

Question 3

how to study sleep function?

Answer 3

observe reduced sleep effect

Question 4

what are proposed functions of sleep:

Answer 4

1. maintain neural plasticity -> synaptic homeostasis hypothesis (SHY) & neuronal firing rate homeostasis
2. Ion homeostasis -> removing harmfull substances?
3. Energy savings
4. Temperature homeostasis

Question 5

what are the sleep-inducing factors?

Answer 5

Hypnotoxin +
1. Adenosine = inhibitory neurotransmitter
2. Muramyl peptides
3. Interleukins
4. Cytokines
5. Prostaglandins

Question 7

One of the proposed functions of sleep is ion homeostasis. What supporting research is there for this hypothesis?

Answer 7

low Potassium concentrations induce sleep, while high Potassium induces waking.