sleep disorders

Question 1

N-REM sleep

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 1

conventionally subdivided into 4 stages defined along the EEG measurement axis

The 4 NREM stages roughly parallel a depth-of-sleep continuum - arousal thresholds lowest in stage 1 and highest in stage 4

EEG pattern in NREM sleep is commonly described as synchronous, with characteristic waveforms like sleep spindles, K-complexes, and high-voltage slow waves

NREM is a relatively inactive yet actively regulating brain in a movable body

Question 2

REM sleep

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 2

defined by EEG activation, muscle atonia, and episodic bursts of rapid eye movements

Typically not divided into stages, although tonic and phasic can be distinguished
- Distinction is based on short lived events such as eye movements that tend to occur in clusters separated by episodes of relative inactivity

The most common marker of REM sleep phasic activity are bursts of rapid eye movements - muscle twitches often accompany REM bursts

Mental activity is associated with dreaming

REM is an activated brain in a paralyzed body

Question 3

measures of sleep

electromyogram (EMG)

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 3

measures muscle response or electrical activity in response to a nerve’s stimulation of the muscle

sleep onset:
may show a gradual diminution of muscle tonus as sleep approaches, but rarely does a discrete EMG change pinpoint sleep onset

Question 4

measures of sleep

electrooculogram (EOG)

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 4

measures eye movements

sleep onset:
shows slow, possibly asynchronous eye movements that usually disappear within several minutes - occasionally coincides with sleep onset

Question 5

measures of sleep

electroencephalogram (EEG)

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 5

measures electrical activity in the brain

sleep onset:
the EEG changes from a pattern of clear rhythmic alpha activity, to a relatively low-voltage, mixed-frequency pattern (stage 1 sleep)
- Usually occurs seconds to minutes after the start of slow eye movements
- However, a number of investigators require the presence of specific EEG patterns - the K-complex or sleep spindle (i.e., stage 2 sleep) - to acknowledge sleep onset
= it is difficult to accept a single variable as marking sleep onset

The consensus is that EEG change to stage 1, usually accompanied by slow eye movements, identifies the transition to sleep, provided that another EEG sleep pattern doesn’t intervene

Question 6

behavioral concomitants of sleep onset

simple behavioral task

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 6

The experimental paradigm is that a participant performs a simple task, that becomes automatic quickly

What is commonly observed is that the simple behavior continues after the onset of slow eye movements and may persist for several seconds after the EEG changes to a stage 1 sleep pattern

The behavior then ceases, usually to recur only after the EEG reverts to a waking pattern

i.e., simple, ‘automatic’ behavior can persist past sleep onset and as one passes in and out of sleep

Question 7

behavioral concomitants of sleep onset

visual response

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 7

Used to show perceptual disengagement from the environment that accompanies sleep onset

A bright light is placed in front of the subject’s eyes, and the subject is asked to respond when a light flash is seen pressing a sensitive microswitch

when the EEG pattern is stage 1/2, the response is absent more than 85% of the time

Question 8

behavioral concomitants of sleep onset

auditory response

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 8

Response to sleep onset is examined with a series of tones played over earphones to a subject who is instructed to respond each time a tone is heard

Reaction times to auditory stimuli become longer in proximity to the onset of stage 1 sleep

Question 9

behavioral concomitants of sleep onset

hypnic myoclonia

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 9

Hypnic myoclonia = a fairly common sleep-onset experience, perceived as a general/localized muscle contraction very often associated with rather vivid visual imagery

Not pathological, however it tends to occur more commonly in association with stress or with unusual sleep schedules

Explanation: a dissociation of REM sleep components → a breakthrough of the imagery component of REM sleep (hypnagogic hallucination) occurs in the absence of the REM motor inhibitory component

Question 10

memory near sleep onset

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 10

The transition from wake to sleep tends to produce a memory impairment

One view is that sleep closes the gate between short- and long-term memory stores

Sleep inactivates the transfer of storage from short- to long-term memory

Encoding of the material before sleep onset is of insufficient strength to allow recall

Question 11

normal pattern/cycle of sleep

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 11

Enters sleep through NREM sleep, REM doesn’t occur until 80 minutes or longer thereafter

NREM and REM sleep alternate throughout the night
- REM episodes usually become longer across the night
- Stage 3 and 4 occupy less time in the 2nd cycle and might disappear altogether from later cycles, as stage 2 expands to occupy the NREM portion of the cycle
- The average period of the NREM-REM cycle is +/- 90-110 minutes

Question 12

first sleep cycle

NREM stages

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 12

Stage 1: usually lasts for a few minutes and can be easily discontinued (1-7 min) = low arousal threshold
- Occurs as a transitional stage throughout the night
- An increase in the amount/percentage of stage 1 sleep points to a severely disturbed sleep

Stage 2: signaled by sleep spindles or K-complexes in the EEG
- 10-25 min
- A more intense stimuli is required to produce arousal
- account for 45% of your time alseep (whole night of sleep)

Stage 3: high-voltage slow wave activity comprising more than 20%, but less than 50% of the EEG record
- Lasts for only a few minutes
- Transition to stage 4

Stage 4: identified when the high-voltage slow-wave activity comprises more than 50% of the record
- Investigators sometimes combine stage 3 and 4 and call it delta sleep, or slow wave sleep (SWS)

Question 13

first sleep cycle

REM stage

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 13

In the first cycle it is usually short-lived (1-5min)

Arousal threshold is variable throughout the night
- Possibly at times, the person’s selective attention to internal stimuli precludes a response
- Arousal stimulus is incorporated into the ongoing dream story rather than producing an awakening

Question 14

first sleep cycle

distribution of sleep stages across the night

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 14

SWS dominates the NREM portion of sleep towards the beginning of the night (i.e., first 1/3 of sleep)
- The preferential distribution of SWS shows a marked response to the length of prior wakefulness

REM episodes are longest on the last one third of the night
- This preferential distribution of REM sleep is thought to be linked to a circadian oscillator, which can be gauged by the oscillation of body temperature

Brief episodes of wakefulness intrude later in the night, usually near REM transitions and are not long enough to be remembered in the morning

Question 15

first sleep cycle

length of sleep

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 15

Varies widely, thus it’s difficult to characterize a ‘normal’ pattern

Volitional control (i.e., staying up late, waking by alarm, etc.,) is among the most significant predictors of the length of nocturnal sleep
- Genetic determinants: the volitional control is superimposed on the genetic determinants of sleep length

As sleep is extended, the amount of REM sleep increases, bc REM sleep depends on the persistence of sleep into the peak circadian time in order to occur

Question 16

factors modifying sleep stage distribution

age

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 16

Strongest and most consistent moderator
- SWS is maximal in young children and decreases markedly with age
- By age 60, SWS might no longer be present, particularly in men

REM sleep as a percentage of total sleep is well maintained into old age

Arousals during sleep increase markedly with age

More heterogeneity in sleep among older populations making it harder to create normative assumptions

Question 17

factors modifying sleep stage distribution

prior sleep history

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 17

A person who has experienced sleep loss on one/more nights shows a sleep pattern that favors SWS during recovery
- REM sleep rebounds on the subsequent recovery nights after an episode of sleep loss
- = SWS tends to be preferentially recovered compared with REM sleep, which tends to recover only after the restoration of SWS

When one is differentially deprived of REM or SWS (through medication or operationally), there’s a preferential rebound of that stage of sleep when natural sleep is resumed

Chronic restriction of nocturnal sleep can result in premature REM sleep
- Associated with hallucinations, sleep paralysis or increased muscle tweaking

Question 18

factors modifying sleep stage distribution

circadian rhythms

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 18

the circadian phase at which sleep occurs affects the distribution of sleep stages

REM sleep, in particular, occurs with a circadian distribution that peaks in the morning hours coincident with the cycle of the core body temperature rhythm
- Thus, if sleep onset is delayed until the peak REM phase of the circadian rhythm - that is, the early morning - REM sleep tends to predominate and can even occur at the onset of sleep

Question 19

factors modifying sleep stage distribution

drug ingestion

Carskadon & Dement (2005)

Normal Human Sleep: An Overview

Answer 19

antidepressants tend to suppress REM sleep

Benzodiazepines tend to suppress SWS and have no consistent effect on REM sleep

Alcohol intake - acute presleep intake can produce an increase in SWS and REM sleep suppression early, which can be followed by REM sleep rebound in the latter portion of the night as the alcohol is metabolized

Marijuana [THC] - minimal sleep disruption, characterized by a slight reduction of REM sleep

Question 20

results

Brautsch et al (2023)

Digital media use and sleep in late adolescence and young adulthood: A systematic review

Answer 20

delayed bedtime: 4/5 studies found an association between digital media use and delayed bedtimes
- E.g., receiving a message @ night was associated w/ later bedtimes among 15-17 yr-olds

sleep onset latency and problem falling asleep: 5 studies - inconsistent results

sleep disturbances: 2/3 studies found an association

short sleep duration: 23 studies - most found an association BUT depended on type of media
- Evidence for mobiles, computers (gaming), internet, social media, general use of screens
- Inconsistent for tablets, game console, and television

early wakening: inconsistent

daytime tiredness and poor daytime function: association found for 1 but inconsistent for 2

poor sleep quality: studies indicated that screen time and use of mobile phone/ smartphone, computer, internet, and social media worsened sleep quality

Question 21

results

summary of results

Brautsch et al (2023)

Digital media use and sleep in late adolescence and young adulthood: A systematic review

Answer 21

General support that the timing of digital media use is important for young people’s sleep

Using digital media at bedtime/nighttime is associated with delayed bedtime, short sleep duration, sleep quality and daytime tiredness

Particularly, the use of smartphone before going to bed and notifications from the smartphone during the night were identified as related to delayed bedtime, short sleep duration, sleep quality, and daytime tiredness

Engagement w/digital media content - gaming, internet use and social media use are associated w/shorter sleep duration, and poor sleep quality

Especially addiction to and problematic use of social media/smartphone are related to poor sleep quality

Question 22

discussion

2 hypotheses about the timing of digital media use

Brautsch et al (2023)

Digital media use and sleep in late adolescence and young adulthood: A systematic review

Answer 22

1. Engagement with digital media may induce mental arousal/hyperarousal, leading to difficulties falling asleep and poor sleep quality
   More ‘communicative’, engaging media (e.g., smartphone social media) has a greater impact than more ‘passive’ media (e.g, television)
2. Exposure to blue light emitted from screens can disrupt the 24-h circadian rhythm and delay the secretion of melatonin

Could be both → as in that the more blue light and the more arousing the media content, the higher the negative impact on sleep quality/duration

Question 23

discussion

gender differences

Brautsch et al (2023)

Digital media use and sleep in late adolescence and young adulthood: A systematic review

Answer 23

Some consistency across studies that call and text interactions, nighttime notifications or availability demands are associated w/immediate disturbed sleep among women

In contrast, in males, having more facebook friends and call/text interactions were associated w/ better sleep

Thus, smartphone use may have a positive impact on sleep among men - although authors argued that this could reflect a person’s sociability

Question 24

obstructive sleep apnea

Carter (2014)

Common Sleep Disorders in Children

Answer 24

Characterized by upper airway obstruction, despite respiratory effort, that disrupts normal sleep patterns and ventilation

Can be associated with obesity, and biological pathology, however, in children, the obstruction is primarily due to enlarged tonsils and adenoids

Onset between 2 and 8 yrs, coinciding with peak tonsil growth, but can manifest at any age

Prevalence: 1-5%

Gender distribution: equal

Untreated OSA is associated with neurobehavioral problems, decreased attention, disturbed emotional regulation, decreased academic performance, impaired growth

Question 25

parasomnias | Carter (2014) ## Footnote Common Sleep Disorders in Children

Answer 25

Defined as undesirable events that accompany sleep and typically occur during sleep-wake transitions Parasomnias such as sleepwalking, sleep talking, confusional arousal, sleep terrors, and nightmares affect up to 50% of children Most parasomnias, occur in the first half of the sleep period during slow wave sleep - typically no memory of the event - However, nightmares typically occur in the last half of the sleep during REM sleep - children typically remember the event Often resolve spontaneously by adolescence, however, 4% will experience recurrence Treatment: centers on reassurance, reducing precipitating factors, and increasing total sleep time

Question 26

behavioral insomnia of childhood | Carter (2014) ## Footnote Common Sleep Disorders in Children

Answer 26

Characterized by a learned inability to fall and/or stay asleep Prevalence is 10%-30% **Sleep onset association type** - characterized by the child's inability/unwillingness to fall asleep or return to sleep in the absence of specific conditions, such as a parent rocking the child to sleep **Limit-setting type** - occurs when parents fail to set appropriate limits, such as when the parents allow the child to sleep in their bed when the child refuses to sleep

Question 27

behavioral insomnia of childhood - treatment | Carter (2014) ## Footnote Common Sleep Disorders in Children

Answer 27

**Prevention is the best treatment** - doctors should educate parents on normal sleep patterns, good sleep hygiene, etc., Parental education - good sleep practices are taught Unmodified extinction: - Child is placed in bed at a predetermined bedtime - Crying is ignored until the next morning - Can be difficult/distressing Graded extinction: - The same as unmodified extinction but with scheduled 'check-ins' - Interactions are calming but last no more than one minute at a time Positive bedtime routines: relaxing / calming activities are implemented before bedtime Faded bedtime: bedtime is delayed until the predicted time of sleep onset to decrease the time the child spends in bed awake Response cost: the child is removed from bed for a specific amount of time if sleep onset doesn't occur within the desired period Scheduled awakenings: - Parents document the pattern of nighttime awakenings - Child is awakened before the normally predicted nighttime awakening, and the frequency of this decreases over time

Question 28

delayed sleep phase disorder | Carter (2014) ## Footnote Common Sleep Disorders in Children

Answer 28

The master circadian clock, located within the suprachiasmatic nucleus controls the timing of sleep and cycles approx every 24 hrs in most In children, habitual sleep-wake times are delayed by at least 2 hours compared w/ socially acceptable times More common in adolescence when the circadian rhythm is thought to lengthen and the child becomes more social - Prevalence in adolescents is 7-16%

Question 29

changes in sleep and sleep EEG with age | Crowley (2011) ## Footnote Sleep and Sleep Disorders in Older Adults

Answer 29

Older adults, particularly older women, disproportionately complain about their sleep In older adults the percentage of lighter sleep (N1/2) increased with age, whereas the percentage of REM and SWS decreased reduction in SWS: - Thought to primarily reflect a decrease in the amplitude of delta activity, rather than the absence of slow wave frequency - Thought to reflect a biological marker of the gradual deterioration of the CNS with age - because in young people SWS is a core component of sleep - Synchronized EEG waveforms, especially the delta frequency in SWS requires large numbers of healthy neurons = not surprising that an aging process that results in neuronal loss would produce changes

Question 30

circadian rhythms | Crowley (2011) ## Footnote Sleep and Sleep Disorders in Older Adults

Answer 30

**Circadian rhythms** = the alteration between wakefulness and sleep + the structure of sleep itself are regulated by the interaction of outputs of the endogenous circadian pacemaker, located in the suprachiasmatic nucleus (SCN) of the hypothalamus and a homeostatic process The **homeostatic process** reflects the need or pressure for sleep which builds up during sustained wakefulness and dissipates during sleep The SCN plays a role in the timing and consolidation of wakefulness - provides a signal that becomes progressively stronger during the daytime hours, peaks at around 9-10pm and dissipates rapidly after the onset of nocturnal melatonin secretion

Question 31

changes in circadian rhythms in aging | Crowley (2011) ## Footnote Sleep and Sleep Disorders in Older Adults

Answer 31

Decline in the amplitude of circadian markers, such as core body temperature, melatonin and cortisol - Decrease in nocturnal melatonin secretion can result in circadian rhythm disruptions, most notably a phase advance - = older adults are much more likely to go to and arise from bed somewhat earlier Neurobehavioral performance: - Optimal performance and alertness across a waking day is thought to result from the wake-dependent decline in alertness and performance being counterbalanced by an increasing wake promoting signal that peaks towards the latter part of the day - Older subjects appear to be less sensitive to the wake-dependent homeostatic influence on performance

Question 32

insomnia and age | Crowley (2011) ## Footnote Sleep and Sleep Disorders in Older Adults

Answer 32

greatest risk factor is age - bcuz: - Excessive use of medication whose side effects often disturb circadian rhythms - Alcohol before sleep - older people appear to be more sensitive to its negative effects - Many comorbid mental and physical disorders - Sleep of an older person is more likely to be disturbed by any factor external to sleep (e.g., noise) relative to the sleep of a younger person

Question 33

sleep disordered breathing and age | Crowley (2011) ## Footnote Sleep and Sleep Disorders in Older Adults

Answer 33

SDB describes a range of respiratory events that occur during sleep from simple snoring at one end of the spectrum to obstructive sleep apnea (OSA) at the other end More common in older adults compared to younger adults It is multifactorial = no single cause SDB leads to excessive daytime sleepiness - older adults may also report insomnia, nocturnal confusion and daytime cog impairment

Question 34

restless leg syndrome and periodic limb movements during sleep | Crowley (2011) ## Footnote Sleep and Sleep Disorders in Older Adults

Answer 34

Prevalence of RLS increases with age + twice as common in women as men PLMS is characterised by periodic episodes of repetitive and stereotypical limb movements during sleep - About 45% of the independently living over 65, meet an arbitrary criterion

Question 35

different tools to diagnose insomnia | Rieman (2023) ## Footnote The European Insomnia Guideline: An update on the diagnosis and treatment of insomnia 2023

Answer 35

1. **Insomnia complaint** - diagnosis relies on subjective complaints; quantitative criteria related to sleep-onset latency, sleep duration or the frequency of nocturnal awakenings do not have to be fulfilled in order to diagnose 2. **Sleep diaries and questionnaires** - evaluation of insomnia should be supported by the use of a sleep diary for at least 7-14 days 3. **Actigraphy** - there is limited clinical support for the mandatory application of actigraphy in the routine evaluation and diagnosis of insomnia 4. **Polysomnography** (PSG) - as important it is for other sleep disorders, PSG is not necessary or sufficient to diagnose insomnia per se 5. **Medical evaluation** - the diagnostic and differential-diagnostic process for chronic insomnia disorder is complex and may require not only clinician's time but many tests and interdisciplinary collaborations between different medical specialties

Question 36

# treatment of insomnia CBT-I - components | Rieman (2023) ## Footnote The European Insomnia Guideline: An update on the diagnosis and treatment of insomnia 2023

Answer 36

**psychoeducation & sleep hygiene:** - by themselves are not sufficient or effective **relaxation therapy:** - Research suggests that abbreviated progressive muscle relaxation, autogenic training and imagery exercises are most frequently used for treatment **sleep restriction therapy:** - The most effective component of CBI - Aims to restrict chance and harness increased sleep pressure to consolidate sleep - When sleep is consolidated → extend time in bed - combination of cog, behavioral, physio pathways to improve sleep and daytime functioning **stimulus control therapy:** - The idea is that insomnia patients exhibit a learned association between the bed/bedroom and being awake (instead of sleeping) - Operant conditioning: go to sleep = reward **cognitive therapeutics:** - Managing and redirecting the thoughts and emotions that keep you awake at night - cog control, paradoxical intention. imagery training & cog restructuring

Question 37

# treatment of insomnia CBT-I - efficacy | Rieman (2023) ## Footnote The European Insomnia Guideline: An update on the diagnosis and treatment of insomnia 2023

Answer 37

Sleep restriction and stimulus control seem to be the most effective components of CBT-I Effects beyond complaints: besides improving sleep, CBT-I can also alleviate depressive/anxiety symptoms, EDS, and QOL CBT-I for insomnia WITH comorbidities: effective Combining CBT-I with pharma: using both treatments together worked well during the initial treatment phase, but after this phase, just continuing with CBT-I alone was better than using both treatments together

Question 38

# treatment of insomnia other cog-beh / psychtherapeutic interventions | Rieman (2023) ## Footnote The European Insomnia Guideline: An update on the diagnosis and treatment of insomnia 2023

Answer 38

Mindfulness-based CBT shows unequivocally positive effects Acceptance-Commitment therapy may be effective - however, more research is needed Hypnotherapy shows some positive effects, but low method qual of studies Intensive sleep retraining: a newer form of behavioral treatment, requiring PSG monitoring - promising evidence

Question 39

# treatment of insomnia exercise, light therapy, music and non-invasive brain stimulation | Rieman (2023) ## Footnote The European Insomnia Guideline: An update on the diagnosis and treatment of insomnia 2023

Answer 39

Exercise - some evidence, however more high-quality research is needed - when added to CBT-I it helped Light therapy - small, positive effects on sleep Music - a possible positive effect, but not enough research Non-invasive brain stimulation - reported positive effects are likely overestimated and at present no recommendation can be given In sum, it is premature to recommend any of these as standalone interventions for insomnia - However, exercise and light therapy can be integrated into CBT-I for additional benefits

Question 40

# treatment of insomnia pharmacological treatments | Rieman (2023) ## Footnote The European Insomnia Guideline: An update on the diagnosis and treatment of insomnia 2023

Answer 40

**Benzodiazepines** & benzodiazepines receptor agonists (short term treatment) - Positive effects when taken in max of 4 weeks - Also comes with side effects (tolerance/dependence, memory impairments) - Need to study the effectiveness in long-term use **Low dose sedating ATDP** - significant but small effects in the short term (4 weeks) **Antipsychotics** - NOT recommended insomnia WITHOUT comorbidities (both short and long term) **Dual orexin receptor antagonists** - mild effects - Can be used up to 3 months (can extended in individual cases) **Antihistaminergic drugs** - insufficient evidence for its use in insomnia treatment, not recommended **Melatonin** - small to medium effects on sleep-related parameters in elderly patients - Fast-release melatonin is NOT recommended **Herbal remedies** - not recommended