Chapter 15

Question 1

Sleep

Answer 1

partially conscious and unconscious

Question 2

Restorative Function

Answer 2

species with higher metabolic rates sleep more

Question 3

Adaptive Hypothesis

Answer 3

amount of sleep an animal engages in depends on the availability of food and on safety consideration

Question 4

Circadian Rhythms

Answer 4

• ‘about day’
  -entertained by environmental cues

Question 5

Suprachiasmatic Nucleus (SCN)

Answer 5

region of the hypothalamus; acts as the main biological clock
- connected to the sun
- regulates sleep
- signals the pineal gland to release melatonin

Question 6

Endogenous Rhythms

Answer 6

rhythms from within the body

Question 7

Melatonin

Answer 7

hormone that induces sleepiness
- SCN controls the production of melatonin
- light resets the biological clock every day by suppressing melatonin secretion

Question 8

Pineal Gland

Answer 8

releases melatonin when signalled by the SCN

Question 9

Ultradian Rhythms

Answer 9

rhythms less than a day in length
- hormone production, unitary output, alertness
- basic rest and activity cycle is a rhythm that is about 90-100 minutes long

Question 10

Stage 1 Sleep

Answer 10

transition to light sleep (1-10 mins)
- alpha/beta waves from wakefulness transition to theta waves when you have fallen asleep
- hypnic/ myoclonin jerks and hypnagogic imagery

Question 11

EEG

Answer 11

used to measure sleep

Question 12

Beta Waves

Answer 12

awake/alert

Question 13

Alpha Waves

Answer 13

relaxed/drowsy
- bigger than beta waves

Question 14

Theta Waves

Answer 14

stage 1
- less frequent that alpha waves

Question 15

Stage 2

Answer 15

deeper sleep (10-25 mins)
- brain waves decelerate, heart rate slows, body temperature decreases, muscles relax, eye movements cease

Question 16

Sleep Spindles

Answer 16

1-2 seconds of rapid brain activity

Question 17

K-complexes

Answer 17

neural excitation followed by neural inhibition

Question 18

Stage 3 and 4 (~30mins)

Answer 18

Slow Wave Sleep
appearance of delta waves
- important to feel rested
- only difference between 3 and 4 is the height and the frequency of the delta waves

Question 19

REM Sleep

Answer 19

waves most similar to beta waves
- occupies 20-25% of our nights sleep
- cycles of REM sleep last between 20min-1hr
- pulse becomes irregular, breathing increase, muscles stop working
- dream the most and most vivid story like dreams
- children spend more time in REM than adults, 50%

Question 20

Hypothesis 1

Answer 20

sleep has evolved to conserve organisms energy
- evidence is strongest for this hypothesis

Question 21

Hypothesis 2

Answer 21

immobilization during sleep is adaptive because it reduces danger

Question 22

Hypothesis 3

Answer 22

sleep helps animals to restore energy and other bodily resources

Question 23

Functions of Slow-Wave Sleep

Answer 23

restoration of the brain
- sleep deprivation produces cognitive deficits

Question 24

Sleep, Plasticity, and Memory

Answer 24

REM sleep important part of memory consolidation; learning and memory
- REM sleep deprivation after learning reduces retention
- period of consolidation followed by clean up
- larger flow of CSB; controlled by glial cells that are transporting the CSB

Question 25

Brain Structures involved in Sleep

Answer 25

use more brain energy during slow wave sleep - no single sleep or waking centre - integrate with the SCN and it's circadian rhythm

Question 26

Brain Stem Arousal Centre's

Answer 26

send activating signals to shier level fo the brain

Question 27

PPT and LDT

Answer 27

fire most rapidly during wakefulness and REM sleep; most slowly during non-REM sleep - driving cortical activation outside non-REM sleep

Question 28

Second Branch; Basil Forebrain

Answer 28

locus coeruleus, raphe nuclei, tuber-mammillary nucleus, and parabrachail nucleus

Question 29

Orexin

Answer 29

released by the lateral hypothalamus and it keeps us awake

Question 30

Ventrolateral Preoptic Nucleus (VLPO)

Answer 30

located in the hypothalamus - neurons inhibit arousal networks - neurons fire 2-4 times faster during non-REM sleep and still more as sleep deepens **inhibits the PPT/LDT**

Question 31

Parafacial Zone

Answer 31

in the medulla - possible involved but not enough research yet

Question 32

PGO Waves

Answer 32

high-voltage brain waves that travel from the pons through the lateral geniculate nucleus of the thalamus to the occipital area - begin 80 seconds before start of REM period - initiate the EEG desynchrony of REM sleep

Question 33

Sublaterodorsal Nucleus

Answer 33

found in the pons - governs switching in and out of REM sleep - believed to be the most important area for REM sleep

Question 34

Insomnia

Answer 34

inability to sleep or to obtain adequate-quality sleep, to the extent that the person feels inadequately rested - not able to get enough stages 3 and 4 sleep - chronic - most common sleep disorder - stress, poor sleep hygiene, withdrawal from depressants, reliance on sleep aids but stopped using them - depression and anxiety;

Question 35

Sleepwalking

Answer 35

originates during deep sleep and results in walking or performing other complex behaviours while still mostly asleep - triggered by stress, alcohol, and sleep deprivation - genetic component

Question 36

Narcolepsy

Answer 36

disorder in which individuals fall asleep suddenly during daytime and go directly into REM sleep - at nighttime, they sleep just like everyone else - usually deficient in orexin but normal levels of melatonin

Question 37

Cataplexy

Answer 37

disorder in which the person has a sudden experience of one component of REM sleep, atonia, and falls to the paralyzed but fully awake - can come hand in hand with narcolepsy

Question 38

REM sleep behaviour disorder

Answer 38

affected individuals are uncharacteristically physically active during REM sleep, often to the point of injuring themselves or their bed partners - more common in men because more common in people who drink and smoke heavily, work in welding and pesticides - within ten years of diagnosis, individuals will develop Parkinson's