Sleep-Wake Disorders Practice Questions

Q: Which sleep disorder is characterized by difficulty in initiating or maintaining sleep, or waking up too early and being unable to return to sleep?

Insomnia. ***Insomnia*** - This disorder is defined precisely by persistent difficulty with **sleep initiation**, **sleep maintenance**, or **early morning awakening** with an inability to return to sleep. - These sleep disturbances lead to **significant distress** or impairment in daily functioning. *Narcolepsy* - Characterized by **overwhelming daytime sleepiness** and sudden attacks of sleep, often accompanied by **cataplexy**. - The primary issue is not difficulty initiating or maintaining night-time sleep, but rather an uncontrollable urge to sleep during the day. *Sleep Apnea* - Involves **repeated episodes of breathing cessation** or shallow breathing during sleep, leading to fragmented sleep and daytime fatigue. - The direct problem is not the inability to fall or stay asleep, but rather the disruption caused by breathing difficulties, though it can indirectly affect sleep maintenance. *Restless Legs Syndrome* - Characterized by an **uncontrollable urge to move the legs**, typically worse in the evening or night, and relieved by movement. - While it can interfere with **sleep initiation** due to discomfort, its defining feature is sensory and motor rather than primary difficulty with the sleep process itself.

Q: A 35-year-old man experiences recurrent awakenings from sleep due to frightening dreams, often involving themes of danger or threat. What is the most likely diagnosis?

Nightmare disorder. ***Nightmare disorder*** - Characterized by **recurrent awakenings** from sleep with detailed recall of **frightening dreams**, often involving threats to survival, security, or self-esteem - Individuals typically become **fully alert** and oriented shortly after awakening and can vividly describe the dream content - Dreams occur predominantly during **REM sleep**, usually in the second half of the night *Sleep terror disorder* - Involves abrupt awakenings from sleep with a panicky scream or cry, accompanied by signs of intense fear like **tachycardia** and **tachypnea** - Individuals are typically **unresponsive to comfort** and have **no recall of the event** or any dream content afterward - Occurs during **non-REM sleep** (Stage 3-4), typically in the first third of the night *Insomnia disorder* - Defined by persistent difficulty with **sleep initiation**, **duration**, **consolidation**, or **quality**, resulting in impaired daytime functioning - While it can involve awakenings, the primary feature is difficulty sleeping, not recurrent frightening dreams that lead to awakenings *Obstructive sleep apnea* - Characterized by **recurrent episodes of upper airway collapse** during sleep, leading to reduced or absent airflow despite respiratory effort - Symptoms include **loud snoring**, observed breathing pauses, and **daytime sleepiness**, but the primary issue is not frightening dreams

Q: Which of the following statements about narcolepsy is false?

Day dreaming. ***Day dreaming*** - While people with narcolepsy experience excessive daytime sleepiness, **daydreaming** is a normal cognitive process and not a characteristic symptom of narcolepsy. - Narcolepsy involves **irresistible urges to sleep** or sudden sleep attacks, which are distinct from simply daydreaming. *Hypnagogic hallucinations* - These are **vivid, often frightening hallucinations** that occur as a person is falling asleep. - They are a common symptom of narcolepsy, along with hypnopompic hallucinations (occurring upon waking). *Cataplexy* - **Cataplexy** is a sudden, brief loss of voluntary muscle tone, often triggered by strong emotions like laughter or anger. - It is a hallmark symptom of **Type 1 narcolepsy** and is caused by the intrusion of REM sleep atonia into wakefulness. *Sudden sleep and decreased REM latency* - Individuals with narcolepsy experience **sudden and irresistible sleep attacks** during the day. - They also have **decreased REM latency**, meaning they enter REM sleep much faster than usual, often within minutes of falling asleep.

Q: Which of the following statements about somnambulism is incorrect?

The patient is in a fully conscious state.. ***The patient is in a fully conscious state.*** - Somnambulism, or **sleepwalking**, involves performing actions while an individual is in a state of **altered consciousness**, not fully conscious. - Individuals experiencing somnambulism are typically in **NREM stage 3 (deep sleep)** and are unaware of their actions with no memory of the event upon awakening. *It is characterized by sleepwalking.* - **Somnambulism** is the medical term for **sleepwalking**, encompassing a range of motor activities performed during sleep. - These activities can vary from sitting up in bed to walking, talking, or even more complex behaviors. *It is classified as a disorder of sleep arousal.* - Somnambulism falls under the category of **NREM sleep parasomnias**, specifically **Non-Rapid Eye Movement Sleep Arousal Disorders** per DSM-5. - These disorders occur during incomplete arousal from NREM sleep, when the brain is transitioning between sleep and wakefulness. *It occurs during NREM stage 3 sleep.* - Somnambulism typically occurs during the **first third of the night** when **NREM stage 3 (slow-wave sleep)** is most prominent. - This is the deepest stage of sleep, characterized by high arousal threshold and decreased responsiveness to external stimuli.

Q: Which of the following conditions is NOT typically associated with increased REM latency?

Narcolepsy. ***Narcolepsy*** - **Narcolepsy** is characterized by pathologically **decreased REM latency**, not increased. - Patients typically enter REM sleep within **15 minutes** of sleep onset (normal is 60-90 minutes). - **Sleep-onset REM periods (SOREMPs)** are a diagnostic hallmark of narcolepsy, seen on multiple sleep latency testing (MSLT). - Since narcolepsy is associated with *decreased* REM latency, it is definitively **NOT associated with increased REM latency**, making it the correct answer to this negation question. *First night effect* - The **first-night effect** refers to sleep disruption and increased REM latency during the first night of polysomnography in an unfamiliar environment. - This is a well-documented phenomenon that **increases REM latency** due to environmental stress and arousal. *SSRIs* - **Selective serotonin reuptake inhibitors (SSRIs)** significantly suppress REM sleep, leading to **increased REM latency** and decreased total REM sleep time. - This effect is mediated by increased serotonin, which inhibits cholinergic neurons involved in REM sleep generation. - SSRIs can increase REM latency by 30-90 minutes beyond normal values. *Restless leg syndrome* - **Restless leg syndrome (RLS)** primarily causes difficulty initiating sleep and sleep fragmentation due to uncomfortable leg sensations. - While RLS disrupts sleep architecture, its effect on REM latency is **variable and inconsistent** - some studies show minimal impact, while chronic sleep deprivation from RLS may actually decrease REM latency during rebound sleep. - However, RLS is not as clearly and consistently dissociated from increased REM latency as narcolepsy is.

Q: All are included in sleep hygiene except which of the following?

Exercising vigorously before sleep. ***Exercising vigorously before sleep*** - **Vigorous exercise** elevates body temperature, heart rate, and stimulates the central nervous system, making it harder to fall asleep and reducing sleep quality. - This practice directly contradicts the principles of sleep hygiene, which promote relaxing activities before bedtime. - While regular exercise is beneficial for sleep, it should be completed at least **3-4 hours before bedtime**. *Healthy diet* - A **balanced diet** and mindful eating patterns are important components of sleep hygiene. - Sleep hygiene recommendations include avoiding **heavy meals, caffeine, and alcohol** close to bedtime, as these can disrupt sleep quality. - Proper nutrition supports the physiological processes necessary for restorative sleep. *Sleeping on time* - Maintaining a **consistent sleep schedule**, even on weekends, helps regulate the body's natural **circadian rhythm**. - This consistency reinforces the sleep-wake cycle, making it easier to fall asleep and wake up naturally. - Going to bed and waking up at the same time daily is a cornerstone of good sleep hygiene. *Sleeping in a dark room* - A **dark environment** signals to the brain that it's time to release **melatonin**, the hormone that promotes sleep. - Exposure to light, especially blue light from screens, can suppress melatonin production and interfere with sleep onset. - Creating an optimal sleep environment (dark, quiet, cool) is a fundamental sleep hygiene principle.

Q: Child wakes up at night sweating and terrified, does not remember the episode - diagnosis?

Night terrors. ***Night terrors*** - **Night terrors** are characterized by partial arousals from **deep non-REM sleep** (typically N3 stage), often accompanied by loud screams, thrashing, and autonomic symptoms like sweating and tachycardia. - The child is very difficult to awaken or comfort during an episode and, crucially, has **no memory of the event** upon waking, which differentiates it from nightmares. *Narcolepsy* - **Narcolepsy** is a chronic neurological condition characterized by overwhelming daytime **sleepiness** and sudden attacks of sleep. - It often involves **cataplexy** (sudden loss of muscle tone triggered by strong emotions) and **hypnagogic/hypnopompic hallucinations**, which are not described. *Nightmares* - **Nightmares** are vivid, frightening dreams that occur during **REM sleep** and typically result in full awakening and the ability to **recall the dream content**. - While they cause fear and distress, episodes do not usually involve the terrified unresponsiveness or lack of recall seen in night terrors. *Somnambulism* - **Somnambulism** (sleepwalking) occurs during **deep non-REM sleep**, and affected individuals may perform complex actions while partially aroused. - While there is amnesia for the event, prominent features like **sweating and intense terror** are not typical components of sleepwalking.

Q: Which of the following statements about narcolepsy is false?

Sleep architecture normal. ***Sleep architecture normal*** ✓ **This is the FALSE statement** - Narcolepsy is characterized by **abnormal sleep architecture**, specifically an **abbreviated latency to REM sleep** (often <15 minutes, compared to normal 90 minutes). - Patients experience **fragmented nighttime sleep** with frequent awakenings and difficulty maintaining continuous sleep. - Sleep studies show **disrupted sleep-wake cycles** and **premature entry into REM sleep**. *Loss of muscle tone* - TRUE statement - **Loss of muscle tone** is the defining feature of **cataplexy**, a hallmark symptom of narcolepsy type 1. - Sudden emotional triggers (laughter, surprise, anger) lead to muscle weakness or paralysis without loss of consciousness. - This reflects neurological dysfunction affecting muscle control regulation during wakefulness. *Hallucination* - TRUE statement - **Hypnagogic hallucinations** (upon falling asleep) and **hypnopompic hallucinations** (upon waking) are common in narcolepsy. - These vivid, dream-like experiences occur during sleep-wake transitions due to intrusion of REM sleep phenomena into wakefulness. - Can involve visual, auditory, or tactile sensations. *Cataplexy* - TRUE statement - **Cataplexy** is a hallmark symptom of **narcolepsy type 1** (narcolepsy with cataplexy). - Involves sudden, brief episodes of bilateral muscle weakness or paralysis triggered by strong emotions. - Results from loss of hypocretin (orexin) neurons in the hypothalamus.

Q: Which of the following parasomnias is characterized by sudden arousal from deep NREM sleep with intense fear and no memory of the event?

Night terrors. ***Night terrors*** - Night terrors are a **parasomnia** that occurs during **NREM sleep**, specifically during stage N3 (slow-wave sleep). - They are characterized by **sudden arousal from sleep** accompanied by screaming, intense fear, and autonomic activation, with **no recall of the event** upon waking. - This combination of features (arousal from deep sleep + intense fear + amnesia) distinguishes night terrors from other NREM parasomnias. *Sleepwalking* - Somnambulism is also a parasomnia occurring during **NREM stage N3** (slow-wave sleep). - However, it involves **complex motor behaviors** during sleep rather than the sudden fearful arousal characteristic of night terrors. - Unlike night terrors, there is usually no associated screaming or expression of intense fear during the episode. *Excessive daytime sleepiness (narcolepsy)* - **Narcolepsy** is a chronic neurological condition characterized by overwhelming daytime drowsiness and sudden sleep attacks. - It involves dysregulation of **REM sleep** processes, including direct entry into REM sleep (sleep-onset REM periods). - This is not a parasomnia and is not associated with NREM sleep phenomena. *Bruxism (teeth grinding)* - Bruxism can occur during **both NREM and REM sleep** but is most frequently observed during lighter NREM stages (N1 and N2). - It involves rhythmic jaw muscle activity without the arousal, fear response, or amnesia seen in night terrors. - While it occurs during NREM sleep, it lacks the characteristic sudden arousal with terror.

Q: What is the primary characteristic feature of Klein-Levin syndrome?

Hypersomnia. ***Hypersomnia*** - **Hypersomnia** is the cardinal and primary characteristic feature of Klein-Levin syndrome, characterized by recurrent episodes of excessive sleepiness lasting days to weeks. - During these episodes, individuals may sleep for **16 to 20 hours a day** and are extremely difficult to awaken. - Episodes are often accompanied by **cognitive disturbances** (confusion, derealization), **behavioral changes** (apathy, hyperphagia, hypersexuality), but **hypersomnia remains the defining feature**. - Normal functioning returns between episodes. *Insomnia* - **Insomnia** (difficulty falling or staying asleep) is the opposite of the key symptom seen in Klein-Levin syndrome. - Klein-Levin syndrome is a disorder of excessive sleep, not sleep deprivation. *Anxiety* - **Anxiety** may occur as a secondary feature or during the distress of episodes, but it is not the primary characteristic feature. - The core pathology manifests as profound sleep disturbance, not an anxiety disorder. *Depression* - **Depression** is sometimes observed during or after episodes of Klein-Levin syndrome, but it is not the primary defining feature. - The diagnostic hallmark is the **recurrent hypersomnia with associated cognitive and behavioral symptoms**, not mood disturbance.

Question 1

Which sleep disorder is characterized by difficulty in initiating or maintaining sleep, or waking up too early and being unable to return to sleep?

Accepted Answer

Insomnia

Answer

Narcolepsy

Answer

Sleep Apnea

Answer

Restless Legs Syndrome

Question 2

A 35-year-old man experiences recurrent awakenings from sleep due to frightening dreams, often involving themes of danger or threat. What is the most likely diagnosis?

Accepted Answer

Nightmare disorder

Answer

Sleep terror disorder

Answer

Insomnia disorder

Answer

Obstructive sleep apnea

Question 3

Which of the following statements about narcolepsy is false?

Accepted Answer

Day dreaming

Answer

Cataplexy

Answer

Sudden sleep and decreased REM latency

Answer

Hypnagogic hallucinations

Question 4

Which of the following statements about somnambulism is incorrect?

Accepted Answer

The patient is in a fully conscious state.

Answer

It is characterized by sleepwalking.

Answer

It is classified as a disorder of sleep arousal.

Answer

It occurs during NREM stage 3 sleep.

Question 5

Which of the following conditions is NOT typically associated with increased REM latency?

Accepted Answer

Narcolepsy

Answer

First night effect

Answer

SSRIs

Answer

Restless leg syndrome

Question 6

All are included in sleep hygiene except which of the following?

Accepted Answer

Exercising vigorously before sleep

Answer

Healthy diet

Answer

Sleeping on time

Answer

Sleeping in dark room

Question 7

Child wakes up at night sweating and terrified, does not remember the episode - diagnosis?

Accepted Answer

Night terrors

Answer

Narcolepsy

Answer

Nightmares

Answer

Somnambulism

Question 8

Which of the following statements about narcolepsy is false?

Accepted Answer

Sleep architecture normal

Answer

Loss of muscle tone

Answer

Hallucination

Answer

Cataplexy

Question 9

Which of the following parasomnias is characterized by sudden arousal from deep NREM sleep with intense fear and no memory of the event?

Accepted Answer

Night terrors

Answer

Sleepwalking

Answer

Excessive daytime sleepiness (narcolepsy)

Answer

Bruxism (teeth grinding)

Question 10

What is the primary characteristic feature of Klein-Levin syndrome?

Accepted Answer

Hypersomnia

Answer

Insomnia

Answer

Anxiety

Answer

Depression

Sleep-Wake Disorders — MCQs

Sleep-Wake Disorders — MCQs

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