week 14: sleep Flashcards
is sleep an active or inactive state
active organized
give some examples of sleeps distinctive physiological fetures
muscle tone
ocular movments
temp
endocrine act
gastro act
cardioresp act
true or false: sleep is the same thoughout lofeslap
false, changes in terms of timing, duration and stages
give 2 examples of how sleep changes throughout life
babies sleep more often but shorter than adults
people over 60 often do not have the deep sleep stage
what are the 5 functions of sleeping
energy conservation theory (decrease in metabolism during sleep)
inactive thoery
restoration theory
brain plasticity
cleansing the brain
explain the energy conservation theory for sleep
decrease in metabolism during sleep
=allows us to conserve energy for wakefulness
explain the inactive theory for sleep
more for animals
=going to sleep when predators are out
explain the restoration theory for sleep
replisninsh brain stores such as glycogen
explain the brain plasticity theory for sleep
allows for memory consultation
(SHY hypothesis=sleep is used to eliminate weak connections and strengthen stronger ones to encode important things)
what is the shy hypothesis
(SHY hypothesis=sleep is used to eliminate weak connections and strengthen stronger ones to encode important things)
explain the cleansing the brain theory for sleep
glymphatic system is active to reduce and remove metabolic waste
true or false: sleep deprivation affects immune system
true
are we more sensitive to pain after sleep deprivation
yes
what are the 2 types of sleep
non rem (non rapid eye movement)
rem (rapid eye movements)
what are the 3 stages in the non rem sleep
n1 (transition to light sleep)
n2 (light sleep)
n3 (deep sleep)
what is the lightest sleep in the non rem called
n1
true or false: transition to light sleep period (n1) takes up large portion of our nigth
false, only 2-5% (only really active when trying to fall asleep or after waking up during night)
which stage of non rem sleep takes up the largest chunk of our sleep
n2 (light sleep)
true or false: most of our night is spent in light sleep (n2)
true
true or false; deep sleep is achievable at any age
false, past 60 often dont have deep sleep)
what is the stage of sleep called in rem
paradoxical sleep
when does dreaming occur
rem (paradoxical sleeP0
percentage of n1
2-5
percentage of n2
45-55
percentage of n3
10-20
percentage of paradoxical sleep
20-25
how long is one sleep cycle lasting
90-120 minutes
true or false: you cycle through rem, n1,n2,n3 every 90-120 minutes
true
in terms of the sleep cycle, majority of n3 (deep sleep) happens when
during first part of the night (and decrease across sleep cycles)
true or false, majority of n3 happens during first part of the night (and increases across sleep cycles)
false it decreases across sleep cycles
when do you get your most restorative sleep
during first part of the night (deep sleep n3)
do you get an increase in REM sleep or n3 sleep as the night progresses
rem
why is it that you can usually remember your dreams in the morning
because as night progresses and gets closer to morning, you increase your REM sleep activity
true or false: deep sleep (n3) is most active at beginning of sleep and REM sleep is most active as night progresses
true
what can you use to record the cortical activity of the scalp
electroencephalograph (EEG)
in EEG< the more neurons that discharge synchronously, the higher or lower the amplitude of oscillations
higher
in EEG< the more neurons that discharge synchronously, the higher the amplitude of oscillations therefore the SLOWER/FASTER the frequency
slower
explain EEG activity during deep sleep
increased activtity in EEG amplitude, slower frequency
explain cortical activity during REM sleep (2 systems)
increase in limbic system
decrease activity of the prefrontal cortex
what can explain why we have heightened emotionality and social inapropraite content of dreams
during REM, we are activating our limbic and triggering emotions without the inhibitory component of our prefrontal cortex
true or false: activation of VLPO induces wakefuless
false, sleep
explain TIPPING of sleep/wake (orexin vs VLPO)
wakefullness: orexin neurons stimulate systems (raphe, LC, thalamus)
sleep= VLPO inhibits orexin neurons, decreasing their activity and therefore decreasing wakeful to induce sleep
true or false: sleep deprivation can affect attention, memory nd executive functions
true
NREM is more involved with episodic or procedural memory
episodic and declarative
REM is more involved with episodic or procedural memory
procedural
define episodic memory
store an retrieve memories related to specific time and place
what are the ways that poor sleep during NREM can affect declarative memory
learning after a poor nights sleep impedes learning
learning prior to bad sleep impedes learning (diff encoding into memory)
true or false, because REM is involved in procedural memory, performance is improved when a post learning sleep period is present
true
what is the cold standard for measuring sleep
polysomnography
what are the 3 miniminalyl required tests for polysomnography
electroencephalography
electrooculography
electromyography
what is point of measuring electroencephalogry during sleep
different sleep stages have distinct signatures of EEG
what is point of measuring electrooculography during sleep
measuring eye movement (Rem vs non rem)
what is point of measuring electromyophrahy during sleep
measuring muscle tone (ex restless leg)
what is the use of polosomn
diagnose sleep disorders, abnormalities and identify sleep stages
what re some of the things a doctor will discuss during initial assessment of sleep
detailed medical and psych husotry
sleep history last 24 h
meds
smoking
alcohol
coffin
activity during day
last meal prior to study
is cannot do a polysomnography, what can a pt use at home as an indirect measure of sleep
actigraphy
what does actigraphy measure
measure mvoment
(indirect measure of sleep)
why is actigraphy used
low cost
high toleratbilty and accessibly
long term recording
environmental cues (exL: light)
what is some of the info collected in a sleep agenda
total horus slept
bedtime/risetime
awakenings
restfulness
naps
what are 3 subjective sleep wake measures and briefly describe)
epworth sleepiness scale (ESS= how likely you are to doze off)
pittsburg sleep quality index (quality of sleep, refreshed, awakenings)
standford sleepiness space (overall sleepiness)
the control of sleep and wakeful depends on what
brainstem and hypothalamic modulation of the thalamus and cortex
true or false: sleep is a inactive state therefore neural activity is reduced
false, it is active
not reduced, altered
true or false, sleep orders are common and not treatable
false they are common but also treatabe
what are the 3 general categories of sleep disorders and their def
parasomnia (abnormal behaviour during sleep)
dyssomnias (inability to sleep or sleep complications)
circadian rhythm disorder
explain behaviours seen in non rem parasomia
sleep walk
somniloquy (sleep talk)
night terrors
periodic limb movement disorders
bruxism (clench jaw)
explain behaviours seen in rem parasomia
REM sleep disorder
nightmare disorder
sleep paralysis
explain REM sleep disorder
do not lose muscle tone when sleeping which can cause you to move
=indivative of later neurodegenerative disorders such as parkinsons and dementia
explain behaviours seen in dyssomnias
hypersomnia (narcolepsy)
insomnia
obstructive sleep apnea
explain some disorders that are classified as circadian rhythm disorders
jet lag (bio clocks and systems not ready to mediate sleep/wake)
delayed / advances sleep phase disorders (sleeping too late or early)
shirt work sleep disorder
non 24h sleep wake disorder
what are some of the cognitive affects of sleep dirosers
diff learning/concetration
decreased alert
decreased effiency
icnrae risk of accidents
what are some of the psychiatrey affects of sleep dirosers
depression
anxiety
stress reactivity
somatic pain
what are some effects of sleep disorders (GENERAL 5)
cognitive
psychoatric
cardiometabilic
increased substance consump
impaired QOL
know the sleep hygiene tips
no phone before bed,
only use bed for sex and sleep
sleep in pitch black
use white noise
put socks to signal bedtime
sleep in cooler temperatures
go to sleep at the same time every day
avoid alc/activity/narcotis/large meals before bed
keep daytime naps below 20
explain why daytime naps should only be under 20 minutes
since we know that we go into deep sleep quickly during beginning of sleep cycle therefore the subsequent sleep at night will be less n3/be less restorative
what is the circadian rhythm
cyclical biological processes within a period of 24 h
what are some of the biological processes associated with circadian rhythm
HR, cortisol levels, temperature, melatonin production, endocrine, sleep wake, muscle strength
are circadian rhythms endogenous or exogenrous
endogenous, produced by organized
circadian rhythms are sensitive to environment… specifically which is the main environmental clue that is the synchronizer of circadian rhytm
loght
what are the 3 aspects you look for in circadian rhythm and briefly explain
period (duration (ie:24 h))
amplitude (peak amplitude of melatonin production, cortical, temperature values)
phase (moment of occurrence of a reference point during a cycle ((ex: when you get a peak melatonin production)
what type is peak melatonin production
5am
true or false: circadian rhythms are capable of entrainment
true
what does circadian rhythm entrainment mean
active process by which the circadian clock synchronizes itself to the day-night environmental cycle)
explain how entrainment will adjust internal clocks to a 24 h schedule
modulate the period and phase of internal clock to make it a 24h circuit
circadian entraiment sises uses period environmental indices known as…
zeitgebers
what is the principle zeitgeber/environmental index used by the circadian
light
true or false: ambient temperature it the main zeitgeber for the circadian rhythm
false, light is
what are 2 general ways to measure circadian rhythm in humans
1) ambulatory measures = timing and regulaturt of sleep wake
=ex: actigraphy, sleep agendas
2) biological clock markers (estimate period, amplitude and phase of endogenous clock)
what are some requirements needed for biological clock markers
have a strong endogenous component
easy to measure (fluctura in an organized manner over 24h)
what are some biological clock markers
minumum temperaturę
dim light melatonin onset
cortisol level
when do we have the lowest body temperature during circadian
2h before waking up (allows us to remain asleep)
true or false: melatonin peak is often at the same time as temperature minumum
true
what are some aspects that can mask body temp as a circadian marker
posture
sleep
stimulating activities
what are some aspects that can mask melatonin production as a circadian marker
light exposure
posture
what are the laboratory protocols to control all masking during circadian rhytm
free running (person can do what they want in constant dim light)
constant routine (decrease effects of behaviour and environment
(measure phase and amplitude of endogenous clock)
forced desynchornicy (imposition of ultra long or ultra short sleep wake s=cycles to see how circadian rhythm adapts)
(measures endogenous period of a clock)
where is the master circadian clock located
suprachiasmic nucleus of the hypothalamus
true or false: the circadian loop is only found in the brain tissues
false, also in peripheral organs
what is the main diff between circadian entrainment in the brain vs in the peripherals
peripheral organs cannot maintain a rhythm on their own (like the SCN) and cannot react to light
=need master clock
why does the SCN act as a type of conductor
peripheral organs cannot maintain a rhythm on their own (like the SCN) and cannot react to light
=need master clock
entrainment by light is enabled through what tract
retinohypothalamuc tract
what is the retinohypothalamuc tract
monosynaptic pahtway (direct pathway from retina to SCN0
=independant of visual pathways
true or false, the retinohypothalamuc tract is independent of visual pathways and explain
yes
specialized retinal cells synapse directly with SCN thru the tract
what are the circadian photoreceptors of the retinohypothalamuc tract
intrinsically photosensitive retinal ganglion cells
what is the photo pigment in intrinsically photosensitive retinal ganglion cells
melanopsin
a Zeitgebers effect depends on what 4 things
1) phase of the endogenous clock relative to the exposition (ie: when exposition occurs)
2) the intensity and dureation of exposition
3) the wavelength of the light
4) the contracts between light and dark to which the subject is exposed (day night differences)
what is the critical point
the point where effect of light shifts from delay to advance
=phase of temp minimun
what is the phase of temp minimum usually occur
around 4/5 am
explain how to induce a small phase delay using light as zeitgeber
expose them to light way before critical point (ex: 12 am)
generate only a small phase delay in temperature rhythm
(ie min temp will now occur at 5 am instead of 4)
