Consciousness & Sleep: A Predictable Schedule - Chapter 5

Question 1

What is Consciousness?

Answer 1

A person’s subjective awareness, including thoughts, perceptions, experiences of the world, and self-awareness

Question 2

Consciousness

Answer 2

1. Is it all just an illusion?
2. Are there neural correlates of consciousness?
3. Are certain structures important or is consciousness an emergent property of the brain operating in its entirety?

Question 3

Hard Problem of Consciousness

Answer 3

The problem in explaining why we have subjective experiences

Question 4

Staying on Schedule

Answer 4

• Circadian Rhythms:
  
  • Biological rhythms with a ~ 24 hour periodicity
    
    1. Entrainment
    2. Endogenous Rhythms

Question 5

Entrainment:

Answer 5

Synchronization between biological rhythms and external cues (zeitgebers)

Question 6

Endogenous Rhythms:

Answer 6

‘Free running’ biological rhythms generated by our body that are independent of zeitgebers
- Genetic feedback loops

Question 7

Light Entrainment

Answer 7

1. Slowly changing levels of background illumination detected by specialized ganglion cells of the retina
2. Light signals communicated to brain via the optic nerve to the optic chiasm
3. Suprachiasmatic nucleus (SCN) situated above optic chiasm receives light information
4. SCN innervates pineal gland to stimulate release of melatonin
5. Melatonin accumulates with darkness and onset of sleep

Question 8

Why Do We Sleep?

Answer 8

1. Restore and repair hypothesis
2. Preserve and protect hypothesis

Question 9

Restore and repair hypothesis

Answer 9

• Sleep restores energy levels and allows for repairs on the body from the day’s activities
  
  • Physiological ‘housekeeping’

Question 10

Preserve and protect hypothesis

Answer 10

• Sleep preserves energy and protects the individual organism from harm
  
  • Sleep differences between predator and prey species