CH 8: Wakefulness & Sleep Flashcards
1
Q
What is Social Jet lag?
A
-Sleep routines disrupted during the weekends
2
Q
What is Sleepdebt?
A
-It occurs when we sleep in a succession of 5 hour night so we can’t be satisfied by one long sleep
3
Q
What are the 7 functions of Good sleep?
A
- Reparing/restoring
- Effective learning & memory
- Better mental/emotional functioning
- Resting muscles
- Decreasing metabolism
- Regular cell maintenance
- Reorganizes synapses
4
Q
What was thought to be the original function of sleep?
A
-To conserve energy
5
Q
How is the conservation of energy accomplished?
A
- Decrease in body temp 1-2 degrees Celcius
- Decrease in muscle activity
6
Q
How might one increase their performance on a task?
A
-Sleep on it!
7
Q
What causes the increased performance on a task?
A
-Increased brain activity in the area of the brain activated by the task
8
Q
What suggests that the brain replays its daily experiences during sleep?
A
-The patterns of activity in Hippocampus during learning were similar to patterns during sleep
9
Q
What happens to the Synapses during sleep?
A
-The brain strengthens some but weakens others
10
Q
What are Sleep Spindles?
A
- Bursts of brain activity that occur during stage 2 of sleep
- They increase in number after new learning
11
Q
What does Sleep Deprivation do to humans?
A
-Hurts all aspects of functioning & complex tasks
12
Q
What does Sleep Deprivation contribute to?
A
- Traffic and workplace incidents
- Irritableness
- Unable to concentrate
- Slurred speech
- Decreased Mental Ability
- Paranoia/Hallucinations
13
Q
What are Endogenous Circadian Rhythms?
A
- Internal Mechs that function over the course of 24 hrs
- Includes sleep cyle, frequency of eating & drinking, Body temp, Secretion of hormones, Urination, Sensitivity to drugs
14
Q
What causes the sensitivity to drugs?
A
-The changes in body temp
15
Q
Do we still function in a Circadian Rhythm in complete darkness?
A
-Yes
16
Q
What is the Purpose of Circadian Rhythms?
A
-To keep our internal workings in phase w/ outside world
17
Q
What is a Free-Running Rhythm?
A
-A rhythm that occurs when no stimuli resets it
18
Q
What is a Zeitgeber?
A
-Any stimulus that resets circadian rhythms
19
Q
What is our primary Zeitgeber?
A
-Sunlight
20
Q
What are some other Zeitgebers?
A
-Exercise, noise, meals & temp
21
Q
What happens if we use something other than Sunlight as a Zeitgeber?
A
-We may experience depression, irritability, & impaired job performance
22
Q
When are young adults most likely to be in a good mood?
A
-late afternoon & early evening
23
Q
What is Jet Lag?
A
- Disruption of Circadian rhythm due to crossing time zones
- Stems from the mismatch of internal clock & external time
24
Q
What does Jet Lag cause?
A
- Sleepiness during day
- Sleeplessness at night
- Impaired concentration
25
Does working at night reliably change the circadian rhythm?
-NO
26
How can people adjust to the Night Shift?
-If they sleep in a very dark room & work under very bright lights at night
27
What does being a Morning person vs Night person depend on?
- Age bc kids are more morning people & teens are more night people
- Partically genetics
28
What are the Mechanisms of the Circadian Rhythm?
- Suprachiasmatic Nucleus (SCN)
- Genes that produce certain proteins
- Melatonin Levels
29
What is the Suprachiasmatic Nucleus?
-Main control center of the circadian rhythms of sleep & temp in a genetically controlled & unlearned manner
30
Where is the Suprachiasmatic Nucleus located?
-Above the Optic Chiasm & part of the Hypothalamus
31
What does damage to the Suprachiasmatic Nucleus result in?
-Less consistent body rhythms= aren't synchronized to the environmental patterns of light & dark
32
How does Light reset the Suprachiasmatic Nucleus?
- via small branch of the optic nerve= Retinohypthalamic path
- It travels directly from retina to SCN
33
What is the Retinohypothalamic path?
-It comes from a special population of Ganglion cells that have their own photopigment= Melanopsin
34
What role does Melanopsin play in Blind People?
-It helps blind people have a sleep-wake cycle
35
How does the Melanopsin work?
-Cells respond directly to light & don't require any input from rods or cones
36
What are the 2 types of genes that are responsible for generating the circadian rhythm?
- Period
| - Timeless
37
What is the role of the Period Genes?
-They produce proteins called PER
38
What is the role of Timeless Genes?
-They produce proteins called TIM
39
What do the PER and TIM proteins do?
-They increase the activity in certain neurons in the SCN = helps w/ sleep & waking
40
What happens if there's mutations in the PER genes?
-Odd circadian rhythms or decreased alertness if you are deprived of a goodnight's sleep
41
What part of the brain does the SCN regulate?
-The Pineal Gland
42
What is the Pineal Gland?
- It is an endocrine gland located under the thalamus
| - It releases Melatonin= hormone that increases sleepiness
43
How much Melatonin does the body produce a day?
30 Micrograms
44
When does Melatonin start to secrete?
2-3 hours before bedtime
45
What is Sleep?
-The moderate decrease in brain activity and decrease in brain response to stimuli
46
What is a Coma?
-The extended period of unconsciousness= low brain activity that remains steady
47
What is a Vegetative State?
- Alternating between periods of sleep & moderate arousal but w/ no awareness of the surrounding
- Shows some automatic arousal to painful stimulus but no purposeful activity
48
What is a Minimally Conscious state?
- Stage higher of vegetative
| - Occasional periods of purposeful action & limited speech comprehension
49
What is Brain Death?
-No sign of brain activity or response to any stimulus
50
What is the role of EEG in sleep?
- It records waveforms
| - It allowed researchers to compare brain activity during different times of sleep
51
What does EEG stand for?
-Electroencephalograph
52
What is a Polysomnograph?
-Combination of EEG and Eye-movement records
53
What are the stages of the Sleep cycle?
N-REM 1
N-REM 2
N-REM 3&4
REM
54
When are Alpha waves present?
-When one begins a state of relaxation=feeling drowsy
55
What is N-REM 1 & what are the wave patterns like?
- Stage of light sleep= claims to be aware & may see fleeing images
- Irregular, jagged, low voltage waves= Theta Waves
56
What is N-REM 2 & what are the wave patterns like?
- Stage where you're definitely asleep but respond to loud noises
- Theres the presence of Sleep-Spindles
- K COMPLEX= sharp high amplitude negative wave followed by smaller/slower positive wave
57
What is N-REM 3&4 and what is the wave pattern like?
- AKA Slow Wave Sleep (SWS)
- Stage where you're in deep sleep, minimal awareness & partially paralyzed
- Slow heart rate, breathing rate, brain activity but highly synchronized neuronal activity
- The waves are slow & have big amplitude= Delta Waves
58
What is REM sleep & what is the wave pattern like?
- AKA Rapid Eye Movement & Paradoxical Sleep
- Stage of Story/ Dream-like state & sleep paralysis
- Postural muscles are relaxed the most in this stage
- Waves are irregular, low voltage & fast=PGO waves
59
Why is REM sleep also called Paradoxical Sleep?
-Bc the waveforms resemble waking wave forms
60
What occurs during REM sleep?
- Discard useless connections
| - Learned motor skills are reinforced
61
What is REM Rebound?
-Where you recover lost sleep
62
What are the order of stages of the sleep cycle?
- 1,2,3,4
| - Then after about an hour you cycle back: 4,3,2,REM
63
What is the key feature of the Sleep Cycle?
-The sequence repeats w/ each cycle & lasts 90 mins
64
What is the definition of Good Sleep?
-When we go through the sleep sequence 4 times which totals to 6-8 hours
65
What is the primary difference of the length between N-REM stages and the REM stage?
- Stages 3 & 4 dominate early in the night & their lengths decrease as the night progresses
- REM sleep dominates later in the night & its length increases as the night progresses
66
What is the Reticular Formation?
-It is responsible for arousal
67
Where is the Reticular Formation located?
-It is part of the midbrain that extends from the medulla to the forebrain
68
What is the role of Pronto-Mesencephalon in Wakefulness?
-It contributes to cortical arousal
69
Where is the Pronto-Mesencephalon located?
-It is part of the Reticular Formation in the midbrain
70
What is the process that contributes to Wakefulness & Arousal?
- Axons extend to the hypothalamus, thalamus, and basal forebrain which releases Acetylcholine, Glutamate, or Dopamine
- These releases have excitatory effects that are spread to areas of the cortex
71
What occurs when the Prontomesencephalon is stimulated?
-It wakes us up & increases alertness in those who are already awake
72
What is the Locus Coeruleus?
-Small structure in the pons & dormant while we're alseep
73
What is the role of the Locus Coerleus in Wakefulness?
-Their axons release Norepinephrine to arouse areas & increase wakefulness
74
What role does the Hypothalamus play in Wakefulness?
- It contains neurons that release Histamine to produce excitatory effects throughout the brain
- The lateral & Posterior nuclei release Orexin
75
What does an Anti-Histamine do?
-They promote sleepiness
76
What is Orexin?
- AKA Hypocretin
| - It is a peptide Neurotransmitter that is needed to stay awake
77
What is the role of Orexin in Wakefulness?
-It is released by cells into the basal forebrain to stimulate neurons responsible for Wakefulness & arousal
78
What releases the inhibitory transmitter GABA?
-Cells in the basal forebrain which is essential to sleep
79
What is the function of GABA?
-It decreases body temp, metabolic rate, and the stimulation of neurons
80
What causes Sleep Walking?
-The brain is awake in one part but asleep in others
81
What is Lucid Dreaming?
-When you are aware that you are dreaming
82
What causes the inability to move?
-When the pons is still in REM while other brain areas wake up
83
What neurotransmitters does the Dorsal Raphe and Pons release?
-Seratonin= interrupts REM sleep
84
What parts of the brain are active during REM sleep?
-The pons & limbic system
85
What parts of the brain are inactive during REM sleep?
-Primary visual cortex, motor cortex, dorsolateral prefornal cortex
86
What does REM deprivation result in?
-High density PGO waves during uninterrupted sleep
87
How does the Pons inhibit motor neurons?
-Sends messages to the spinal chord, this inhibition controls the body's large muscles
88
What 2 neurotransmitters is REM sleep regulated by?
-Acetylcholine and Seratonin
89
What role does Acetylcholine play in REM sleep?
-If the receptors are stimulated, it will quickly move people into REM
90
What is Insomnia?
-It is a sleep disorder where people can't get enough sleep
91
What is the cause of Insomnia?
-Noise, stress, pain medication, epilepsy, parkinson's disease, depression, anxiety
92
What happens if you are dependent on Sleeping pills?
-It shifts our circadian rhythm & can result in insomnia
93
To fight Jet Lag, what should you do?
-Stay in the sun! & don't sleep in extreme cases
94
What is Sleep Apnea?
-Sleep disorder where you can't breathe for a long period of time
95
What is Narcolepsy?
-Sleep disorder where you have frequent periods of sleepiness=Lack of orexin
96
What are the 4 main symptoms of Narcolepsy?
- Gradual/sudden attack of sleepiness
- Occasional Caraplexy= muscle weakness triggered by strong emotions
- Sleep paralysis
- Hypnagogic Hallucinations=dreamlike experiences where the person has trouble seeing if it was a dream or not
97
What causes Narcolepsy?
-The lack of Hypothalamic cells that produce & release Orexin
98
What are some possible treatments of Narcolepsy?
- Ritalin
| - SSRI's
99
What is REM behavior disorder associated with?
- Vigorous movement during REM sleep= acting out dreams
| - Damage to the pons which inhibit the spinal neurons to control large muscle movements
100
What population is most likely to experience REM behavioral disorders?
-Elderly/ Older men w/ brain diseases like Parkinson's
101
What are Night Terrors?
- Experiences of intense anxiety where a person wakes up screaming in terror
- Most common in younger children
- It occurs in N-REM sleep
102
When does Sleep-Talking occur?
-In N-REM and REM sleep
103
What are the key characteristics of Sleep-Walking?
- It runs in families but mostly occurs in kids
| - Occurs in stages 3&4
104
What are the 2 Biological Theories of Dreaming?
- Activation-Synthesis Hypothesis
| - Neurocognitive Hypothesis
105
What does the Activation-Synthesis Hypothesis of dreaming imply?
- Dreams begin w/ spontaneous activity in the Pons = activates other areas of the cortex
- The cortex synthesizes story from pattern of activation
- Normal sensory info is sometimes integrated but usually isn't
106
What does the Neurocognitive Hypothesis of Dreaming Imply?
- Dreams are similar to thinking, just under unusual circumstances
- External or Internal stimulation activates parts of the Parietal, Occipital, & Temporal cortex
- Stimulation is combined w/ recent memories & info from senses
107
What activities are suppressed in the Neurocognitive Hypothesis?
- Motor neurons
- Neurons in spinal cord
- Prefrontal cortex
108
What activities are high in the Neurocognitive Hypothesis?
- Lower part of the Parietal Cortex (visual/spatial)
| - Hypothalamus/ Amygdala (emotional)
