Sleep-Wake Disorders — MCQs
On this page
Which of the following statements about somnambulism is incorrect?
Which of the following statements about sleep is incorrect?
Which of the following conditions is NOT typically associated with increased REM latency?
All are included in sleep hygiene except which of the following?
Child wakes up at night sweating and terrified, does not remember the episode - diagnosis?
Which of the following parasomnias is characterized by sudden arousal from deep NREM sleep with intense fear and no memory of the event?
What is the primary characteristic feature of Klein-Levin syndrome?
Which of the following statements about narcolepsy is false?
Cataplexy is characterized by?
Narcolepsy is associated with?
Sleep-Wake Disorders Indian Medical PG Practice Questions and MCQs
Question 71: Which of the following statements about somnambulism is incorrect?
- A. The patient is in a fully conscious state. (Correct Answer)
- B. It is characterized by sleepwalking.
- C. It is classified as a disorder of sleep arousal.
- D. It occurs during NREM stage 3 sleep.
Explanation: ***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.
Question 72: Which of the following statements about sleep is incorrect?
- A. Sleepwalking occurs during NREM sleep
- B. Dreams occur during REM sleep
- C. REM sleep is also called paradoxical sleep
- D. REM sleep occurs before NREM sleep (Correct Answer)
Explanation: ***REM sleep occurs before NREM sleep*** - This statement is incorrect as **NREM (Non-Rapid Eye Movement) sleep always precedes REM (Rapid Eye Movement) sleep** in a typical sleep cycle. - The sleep cycle begins with NREM stages (N1, N2, N3) and then progresses to REM sleep. *REM sleep is also called paradoxical sleep* - This statement is correct because during **REM sleep**, brain activity is very high, similar to wakefulness, yet the body experiences **muscle atonia (paralysis)**. - The paradoxical nature refers to the disconnect between an active brain and a paralyzed body. *Sleepwalking occurs during NREM sleep* - This statement is correct; **sleepwalking (somnambulism)** is a parasomnia that typically occurs during **deep NREM sleep**, specifically stage N3 (slow-wave sleep). - The brain state during NREM sleep allows for motor activity without full consciousness or memory of the event. *Dreams occur during REM sleep* - This statement is correct; while dreams can occur in NREM sleep, **vivid, detailed, and memorable dreams are most common and intense during REM sleep**. - The elevated brain activity and characteristics of REM sleep are conducive to the complex narrative and emotional content of dreams.
Question 73: Which of the following conditions is NOT typically associated with increased REM latency?
- A. First night effect
- B. SSRIs
- C. Restless leg syndrome
- D. Narcolepsy (Correct Answer)
Explanation: ***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.
Question 74: All are included in sleep hygiene except which of the following?
- A. Healthy diet
- B. Exercising vigorously before sleep (Correct Answer)
- C. Sleeping on time
- D. Sleeping in dark room
Explanation: ***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.
Question 75: Child wakes up at night sweating and terrified, does not remember the episode - diagnosis?
- A. Narcolepsy
- B. Nightmares
- C. Night terrors (Correct Answer)
- D. Somnambulism
Explanation: ***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.
Question 76: Which of the following parasomnias is characterized by sudden arousal from deep NREM sleep with intense fear and no memory of the event?
- A. Night terrors (Correct Answer)
- B. Sleepwalking
- C. Excessive daytime sleepiness (narcolepsy)
- D. Bruxism (teeth grinding)
Explanation: ***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.
Question 77: What is the primary characteristic feature of Klein-Levin syndrome?
- A. Insomnia
- B. Anxiety
- C. Depression
- D. Hypersomnia (Correct Answer)
Explanation: ***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 78: Which of the following statements about narcolepsy is false?
- A. Loss of muscle tone
- B. Hallucination
- C. Cataplexy
- D. Sleep architecture normal (Correct Answer)
Explanation: ***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.
Question 79: Cataplexy is characterized by?
- A. Sudden loss of muscle tone (Correct Answer)
- B. Generalized muscle weakness
- C. Hypnopompic hallucinations
- D. Nocturnal penile tumescence
Explanation: ***Sudden loss of muscle tone*** - **Cataplexy** is specifically defined by a sudden, brief loss of **muscle tone** while awake, often triggered by strong emotions like laughter or anger. - This loss of muscle tone is similar to the muscle paralysis experienced during **REM sleep**, but occurs while the individual is fully conscious. *Hypnopompic hallucinations* - **Hypnopompic hallucinations** are vivid, dream-like experiences that occur when waking up from sleep. - While frequently associated with **narcolepsy**, they are not the defining characteristic of **cataplexy** itself. *Generalized muscle weakness* - While cataplexy involves muscle weakness, it is a **sudden and transient loss of tone** rather than a sustained, generalized weakness. - **Generalized muscle weakness** can be a symptom of many other conditions and does not accurately describe the abrupt, emotion-triggered nature of cataplexy. *Nocturnal penile tumescence* - **Nocturnal penile tumescence (NPT)** is the occurrence of spontaneous erections during sleep and is a normal physiological process. - It is used in the differential diagnosis of erectile dysfunction to distinguish between organic and psychogenic causes, and has no direct relation to **cataplexy**.
Question 80: Narcolepsy is associated with?
- A. Late age of onset
- B. Hypnagogic hallucination (Correct Answer)
- C. Decreased NREM sleep
- D. Normal sleep architecture
Explanation: ***Hypnagogic hallucination*** - **Hypnagogic hallucinations** are vivid, dream-like perceptual experiences occurring at **sleep onset** and are one of the **classic tetrad features** of narcolepsy. - They occur in **30-60% of narcolepsy patients** and result from the intrusion of **REM sleep phenomena** into the transition from wakefulness to sleep. - These hallucinations reflect the **REM sleep dysregulation** that is central to narcolepsy pathophysiology. - Other tetrad features include **excessive daytime sleepiness, cataplexy, and sleep paralysis**. *Late age of onset* - Narcolepsy typically has an **early age of onset**, most commonly between **10-25 years** (adolescence and young adulthood). - Peak onset is around **15 years of age**. - Late-onset narcolepsy is uncommon and may suggest secondary causes. *Normal sleep architecture* - Narcolepsy is characterized by **disrupted sleep architecture**, not normal architecture. - Key abnormalities include **sleep-onset REM periods (SOREMPs)**, where patients enter REM sleep within **15 minutes** of sleep onset, bypassing normal NREM stages. - Nocturnal sleep is **fragmented** with frequent awakenings. *Decreased NREM sleep* - While narcolepsy involves **REM sleep dysregulation** with premature REM entry, characterizing it simply as "decreased NREM sleep" is not the standard clinical description. - The primary pathology is **abnormal REM sleep timing and distribution**, including SOREMPs during daytime naps and nighttime sleep. - The focus is on **REM sleep intrusion** rather than NREM reduction per se.
Practice by Chapter
Normal Sleep Physiology
Practice Questions
Insomnia Disorder
Practice Questions
Hypersomnolence Disorders
Practice Questions
Narcolepsy
Practice Questions
Breathing-Related Sleep Disorders
Practice Questions
Circadian Rhythm Sleep-Wake Disorders
Practice Questions
Parasomnias
Practice Questions
Sleep-Related Movement Disorders
Practice Questions
Sleep Disorders in Psychiatric Conditions
Practice Questions
Pharmacotherapy for Sleep Disorders
Practice Questions
Cognitive-Behavioral Therapy for Insomnia
Practice Questions
Sleep Hygiene and Other Non-pharmacological Approaches
Practice Questions
Want unlimited practice?
Get full access to all questions, explanations, and performance tracking.
Start For Free