Sleep Flashcards
What are the two main phases of sleep?
The two main phases are Rapid Eye Movement (REM) sleep and Non-Rapid Eye Movement (NREM) sleep.
What are the stages of NREM sleep?
NREM sleep is divided into three stages: N1 (light sleep), N2 (deeper sleep), and N3 (deepest sleep or slow-wave sleep).
What percentage of sleep is spent in NREM sleep?
Approximately 75% of sleep is spent in NREM stages.
What EEG pattern is seen during wakefulness with eyes open?
Beta waves – highest frequency, lowest amplitude.
Which EEG pattern is predominant during drowsiness with closed eyes?
Alpha waves.
What are sleep spindles and K-complexes, and in which stage do they occur?
Sleep spindles are bursts of neuronal activity, and K-complexes are large delta waves. They occur in N2 sleep.
What stage of sleep is associated with dreaming and nightmares?
REM sleep.
What stage of sleep is known as slow-wave sleep (SWS)?
N3 sleep.
What physiological changes occur during REM sleep?
Loss of skeletal muscle tone, erratic breathing, and penile/clitoral tumescence.
How does sleep progress through the night?
Progression: N1 → N2 → N3 → N2 → REM.
What are the main classifications of sleep disorders?
Insomnia, sleep-related breathing disorders, hypersomnolence disorders, circadian rhythm disorders, parasomnias, and sleep-related movement disorders.
What is insomnia?
A sleep disorder characterized by difficulty falling or staying asleep, leading to daytime impairment.
What are the risk factors for insomnia?
Older age, female sex, chronic pain, psychiatric disorders, stress, alcohol, caffeine, and certain medications.
What is the gold standard test for diagnosing sleep-related breathing disorders?
Polysomnography (PSG).
What non-pharmacologic treatment is first-line for chronic insomnia?
Cognitive Behavioral Therapy for Insomnia (CBT-I).
What medication class is commonly used for short-term insomnia management?
Benzodiazepines and non-benzodiazepine receptor agonists (BZRAs).
Which hormone is primarily responsible for regulating the sleep-wake cycle?
Melatonin.
What is obstructive sleep apnea (OSA)?
A sleep disorder characterized by upper airway obstruction leading to intermittent hypoxia and sleep fragmentation.
What is the first-line treatment for obstructive sleep apnea?
Continuous Positive Airway Pressure (CPAP) therapy.
What is narcolepsy?
A sleep disorder with excessive daytime sleepiness, cataplexy, and abnormal REM sleep transitions.
What is cataplexy?
Sudden loss of muscle tone triggered by strong emotions, commonly seen in narcolepsy type 1.
What is the key diagnostic test for narcolepsy?
Multiple Sleep Latency Test (MSLT).
What neurotransmitter deficiency is associated with narcolepsy type 1?
Orexin (hypocretin) deficiency.
What are common REM-related parasomnias?
Nightmare disorder, REM sleep behavior disorder, and sleep paralysis.
What is REM sleep behavior disorder?
A condition where muscle atonia is absent during REM sleep, leading to dream enactment behaviors.
What neurodegenerative diseases are associated with REM sleep behavior disorder?
Parkinson’s disease and Lewy body dementia.
What are NREM-related parasomnias?
Sleepwalking, night terrors, and confusional arousals.
What stage of sleep is associated with night terrors and sleepwalking?
N3 (slow-wave sleep).
What is restless leg syndrome (RLS)?
A sleep-related movement disorder characterized by an irresistible urge to move the legs, often relieved by movement.
What deficiency is commonly associated with restless leg syndrome?
Iron deficiency.
What pharmacologic treatment is used for restless leg syndrome?
Dopamine agonists (e.g., pramipexole, ropinirole).
What is circadian rhythm sleep-wake disorder?
A disorder characterized by misalignment between the endogenous circadian rhythm and sleep-wake schedules.
What are common types of circadian rhythm sleep-wake disorders?
Shift work disorder, jet lag disorder, delayed and advanced sleep phase disorders.
Which population is most affected by delayed sleep phase disorder?
Adolescents and young adults.
What is the primary treatment for shift work sleep disorder?
Light therapy and melatonin supplementation.
What is Kleine-Levin syndrome?
A rare hypersomnia disorder characterized by recurrent episodes of excessive sleep, hyperphagia, and hypersexuality.
What is sleep paralysis?
A transient inability to move or speak while falling asleep or waking up, often with hallucinations.
What is the function of sleep spindles?
They aid in memory consolidation and sensory processing during sleep.
What is advanced sleep phase disorder?
A circadian rhythm disorder where sleep onset and wake-up times are earlier than desired, common in older adults.
What is polysomnography (PSG) used to diagnose?
Sleep apnea, periodic limb movement disorder, REM sleep behavior disorder, and nocturnal seizures.
What is actigraphy?
A non-invasive method to assess sleep patterns by recording body movements.
Which sleep disorder is commonly associated with depression?
Insomnia.
What cardiovascular risk is associated with obstructive sleep apnea?
Hypertension, atrial fibrillation, and stroke.
Which sleep stage is most important for physical restoration?
N3 (slow-wave sleep).
Which sleep stage is most important for cognitive function and memory consolidation?
REM sleep.
How does aging affect sleep architecture?
Increased sleep latency, more nighttime awakenings, and reduced slow-wave sleep (N3).
What is the effect of alcohol on sleep?
Disrupts REM sleep and increases sleep fragmentation.
What is paradoxical sleep?
Another name for REM sleep due to its EEG resemblance to wakefulness.
What is the first-line treatment for nightmare disorder?
Cognitive behavioral therapy and imagery rehearsal therapy.
What is the difference between sleep terrors and nightmares?
Sleep terrors occur in N3 sleep and lack recall, while nightmares occur in REM sleep and are vividly remembered.
What are common medications that disrupt sleep?
Caffeine, beta-blockers, SSRIs, corticosteroids, and stimulants.
What is sleep inertia?
A state of grogginess and reduced alertness upon waking from deep sleep.
How long does a typical sleep cycle last?
Approximately 90 minutes.
What is the function of K-complexes?
They help suppress arousal and promote sleep continuity.
What is the treatment for severe chronic insomnia?
Cognitive behavioral therapy combined with pharmacologic therapy (e.g., sedative-hypnotics).
