Medsci 4930F Study Set Lecture Only Questions With
Complete Solutions
sleep questions
-why we need to sleep and which stages are important: what is
the architecture of sleep, what is the weight of quality vs
quantity.
what happens if u dont sleep properly, what are models to teach
us abt it, what happens if u r born w/ dysfunctional SCN we r
trying to answer all of these
Sleep
sleep is where u go unconscious, can go conscious w/ stimuli
different from a coma where u dont wake up
fundamental for optimal physical and mental health
quality and quantity matter
stages of sleep are periodic w/ many factors impacting it,
beyond just genes lifestyle too
-circadian and sleep-wake cycles evolved together, in parallel. -
purpose was to make sure that timing of internal events relative
to each other, and to extenal enviro is coordinated
outcome: maximize survival and lifespan
,intrinsic biological clocks control various homeostatic functions
in the body incl sleep and wake cycles
sleep architecture (cycles)
sleep cycles usually 4-5 cycles
stage 1: some noise wakes u up
then get deeper until stage 3: slower wave sleep, hard to wake
up. here u can repair yourself and consolidate memory
then have REM
video for sleep architecture
non REM is stage 1-4
stage 3-4 is slow wave sleep, sleep walking can occur,
consolidation of declarative memories. First rem is abt 10 min
long, then gets longer
u are paralyzed in REM except for eyes and diaphgram. Brain is
active, have increased ANS, and consolidate procedural
memories
polysomnography7
help study sleep can identify disorders such as:
narcolepsy: sleep attacks during the day (randomly sleep)
sleep apnea- cant breathe during sleep
REM sleep: sleep behaviour, acting out dreams in sleep
-unusual sleep behaviours: eg sleep walking, moving
excessively, rhytmic movements
periodic limbic movement disorder: unconscious extension and
whatnot of limbs
,2-process model of sleep recognition
circadian processes: guided by SCN, helps create sleep
periodicity, and partly in the individual's control.
- process C (Circadian process): circadian reg of sleep driven
by circadian pacemaker, such that sleep drive oscillates w/ a
periodicity that is typically entrained to the environmental LD
cycle
Homeostatic process (process S) : homeostatic reg of sleep
driven by sleep debt, or how long and individual has been
awake
-teaches and forces u to sleep, increases pressure for sleep
-no matter who much u resist. u sleep
-helps with survival
process C and S video
video 1:
-process C: internal 24 hour clock present in humans and many
other organisms
-controlled by circadian clock eg. how alert someone is
process S: sleep pressure builds up as a person is awake,
alleviates as the person sleeps. sleep pressure increases
propensity to sleep
-sleep pressure opposes the circadian alerting signal -at the start
of the night, sleep because of high sleep pressure, and at second
part of night, stay asleep because of low circadian alerting signal
, video 2:
-can liken process S to hunger -buildup if we do not eat for a
long time, but cannot eat for a while after a meal
-get best sleep when process S and C work together -however,
disruptions can occur
-eg. shift work -work all night, fall asleep fast, but wake up soon
after due to daily rhythms (process C)
convergence of process C and S
circadian timing system and sleep can interact on many levels:
eg acute effects of slow wave sleep on neural activity in SCN
effect of circadian timing on REM sleep
variation in clock gene PER3 on homeostatic sleep reg
can have the genome studies to see how diff alleles of same gene
can impact sleep
-gives insight into how genetics can define sleep disorders as
well and influence circadian systems in some way
Neuronal and hormonal mechanisms of circadian sleep reg
from animal experiments we learn that
SCN is primary driver of process C
SCN plays clear role in sleep timing
rhythmic release of the pineal hormone melatonin plays a role in
timing of sleep in mammals
Complete Solutions
sleep questions
-why we need to sleep and which stages are important: what is
the architecture of sleep, what is the weight of quality vs
quantity.
what happens if u dont sleep properly, what are models to teach
us abt it, what happens if u r born w/ dysfunctional SCN we r
trying to answer all of these
Sleep
sleep is where u go unconscious, can go conscious w/ stimuli
different from a coma where u dont wake up
fundamental for optimal physical and mental health
quality and quantity matter
stages of sleep are periodic w/ many factors impacting it,
beyond just genes lifestyle too
-circadian and sleep-wake cycles evolved together, in parallel. -
purpose was to make sure that timing of internal events relative
to each other, and to extenal enviro is coordinated
outcome: maximize survival and lifespan
,intrinsic biological clocks control various homeostatic functions
in the body incl sleep and wake cycles
sleep architecture (cycles)
sleep cycles usually 4-5 cycles
stage 1: some noise wakes u up
then get deeper until stage 3: slower wave sleep, hard to wake
up. here u can repair yourself and consolidate memory
then have REM
video for sleep architecture
non REM is stage 1-4
stage 3-4 is slow wave sleep, sleep walking can occur,
consolidation of declarative memories. First rem is abt 10 min
long, then gets longer
u are paralyzed in REM except for eyes and diaphgram. Brain is
active, have increased ANS, and consolidate procedural
memories
polysomnography7
help study sleep can identify disorders such as:
narcolepsy: sleep attacks during the day (randomly sleep)
sleep apnea- cant breathe during sleep
REM sleep: sleep behaviour, acting out dreams in sleep
-unusual sleep behaviours: eg sleep walking, moving
excessively, rhytmic movements
periodic limbic movement disorder: unconscious extension and
whatnot of limbs
,2-process model of sleep recognition
circadian processes: guided by SCN, helps create sleep
periodicity, and partly in the individual's control.
- process C (Circadian process): circadian reg of sleep driven
by circadian pacemaker, such that sleep drive oscillates w/ a
periodicity that is typically entrained to the environmental LD
cycle
Homeostatic process (process S) : homeostatic reg of sleep
driven by sleep debt, or how long and individual has been
awake
-teaches and forces u to sleep, increases pressure for sleep
-no matter who much u resist. u sleep
-helps with survival
process C and S video
video 1:
-process C: internal 24 hour clock present in humans and many
other organisms
-controlled by circadian clock eg. how alert someone is
process S: sleep pressure builds up as a person is awake,
alleviates as the person sleeps. sleep pressure increases
propensity to sleep
-sleep pressure opposes the circadian alerting signal -at the start
of the night, sleep because of high sleep pressure, and at second
part of night, stay asleep because of low circadian alerting signal
, video 2:
-can liken process S to hunger -buildup if we do not eat for a
long time, but cannot eat for a while after a meal
-get best sleep when process S and C work together -however,
disruptions can occur
-eg. shift work -work all night, fall asleep fast, but wake up soon
after due to daily rhythms (process C)
convergence of process C and S
circadian timing system and sleep can interact on many levels:
eg acute effects of slow wave sleep on neural activity in SCN
effect of circadian timing on REM sleep
variation in clock gene PER3 on homeostatic sleep reg
can have the genome studies to see how diff alleles of same gene
can impact sleep
-gives insight into how genetics can define sleep disorders as
well and influence circadian systems in some way
Neuronal and hormonal mechanisms of circadian sleep reg
from animal experiments we learn that
SCN is primary driver of process C
SCN plays clear role in sleep timing
rhythmic release of the pineal hormone melatonin plays a role in
timing of sleep in mammals
