Circadian Rhythms and Sleep Regulation Quiz

The brain region primarily responsible for regulating the circadian rhythm, receiving light/dark information from the eyes.

A natural, internal process that regulates the sleep-wake cycle based on daily light-dark cycles.

A neuropeptide secreted by the lateral hypothalamus that promotes wakefulness by influencing arousal systems and VLPO.

A sleep-promoting nucleus influenced by orexin, contributing to a stable sleep state.

The accumulated need for sleep that increases over time and without adequate sleep, affecting the sleep-wake cycle.

A state of temporary muscle paralysis during REM sleep, caused by descending connections from REM-on neurons.

Large brain waves during deep sleep (N3), caused by oscillations between the thalamus and cortex.

Electrical activity in cortical association areas during REM sleep, not synchronized.

The progression through sleep stages at night, including duration, frequency, and awakenings.

The first stage of sleep, characterized by theta rhythm, easily awakened.

Sleep stage characterized by theta waves, K complexes, sleep spindles, increased difficulty to awaken.

Deep sleep stage characterized by delta waves, hard to awake from.

The length of time spent in each sleep stage changes dramatically through different life stages.

REM sleep occurs later in the sleep cycle, after passing through the deeper sleep stages (such as N3).

Young children spend a large portion of their sleep in N3 and REM stages.

A type of narcolepsy characterized by cataplexy, often triggered by strong emotions, and includes frequent daytime naps with REM sleep.

Autoimmune response (often linked to HLA DQB1*06:02) or potential molecular mimicry may cause the loss of orexin neurons in the brain.

Usually involves antidepressants that boost noradrenaline or serotonin to stimulate "REM-off" neurons in the brain, to improve wakefulness.

A movement disorder characterized by an irresistible urge to move the legs, often triggered by rest or drowsiness.

A sleep disorder characterized by repetitive, involuntary leg movements during sleep.

The cause of RLS/PLMD is not fully understood, but it is linked to potential iron deficiency (especially in the brain), and problems with dopamine signaling.

Drugs that stimulate dopamine receptors, frequently used to treat RLS and some movement disorders associated with dopamine issues.

A network of brain structures that controls movement, critically dependent on dopamine.

Dopamine release from brain movement centers might be poorly regulated in relation to the circadian rhythm of RLS, suggesting a possible cause of this issue.

A sleep disorder characterized by pauses in breathing during sleep.

The process of synchronizing the SCN's internal cycle to external light-dark cycles.

Nerve fibers that carry light information from the retina to the SCN for entrainment.

Melatonin helps entrain the circadian rhythm to light-dark cycles, influencing sleep and various physiological processes.

Melatonin receptors that plays a crucial role in the entrainment of the SCN to light-dark cycles.

The time it takes to fall asleep.

The internal need for sleep that builds up over time.

A molecule whose buildup is likely responsible for the homeostatic sleep drive.

Caffeine blocks adenosine receptors, preventing the drive for sleep.

The body's response to physical or psychological stressors that cannot be managed by homeostasis.

A sleep disorder characterized by excessive daytime sleepiness, intrusion of REM sleep characteristics into wakefulness, and sometimes cataplexy.

Sudden temporary loss of muscle tone associated with narcolepsy.

Inability to move when falling asleep or waking up.

Neurons in the lateral hypothalamus that promote wakefulness.

Frequent and overwhelming urges to sleep during the day that interfere with daily life.

A stage of sleep characterized by rapid eye movements, dreaming, and decreased muscle tone.

A sleep disorder characterized by repeated pauses in breathing during sleep due to an obstruction in the airway.

Diagnosis of OSA involves identifying 5 or more episodes of interrupted breathing (apnea or hypopnea) in an hour of sleep.

Temporary cessation of airflow during sleep for at least 10 seconds, despite respiratory effort.

Significant reduction (≥ 30%) in airflow for at least 10 seconds during sleep, accompanied by oxygen desaturation or waking.

Diagnostic test that monitors brain waves, eye movements, muscle activity, and breathing during sleep.

Excessive daytime sleepiness, fatigue, difficulty concentrating, and other related symptoms.

Upper airway structures collapse during sleep due to decreased muscle tone.

Excess upper body fat narrows the pharyngeal airway and reduces chest wall compliance, contributing to OSA.

A narrower pharyngeal airway, due to various factors, is more prone to collapse.

Nasal congestion/blockage can worsen pharyngeal obstruction, even with the mouth open.

First-degree relatives of individuals with OSA are more likely to develop the disorder.

OSA prevalence tends to increase with age.

Obstructive sleep apnea is linked to diabetes, hypertension, and atrial fibrillation.

Individuals with OSA may have an exaggerated response to increases in carbon dioxide levels, making them more likely to experience intermittent breathing pauses.

Respiratory effort to maintain breathing is still present even during apneic episodes.

Diagnosing Obstructive Sleep Apnea (OSA) involves a sleep history (from an observer), a physical exam (for hypertension, heart issues, and airway obstruction signs), and a polysomnogram (PSG) as the gold standard.

The gold standard test for OSA, recording nasal airflow, chest/abdomen movement, and pulse oximetry during sleep.

A parasomnia involving automatic motor activities during sleep, most common in children and adolescents, occurring in N3 sleep.

Parasomnia involving a sudden awakening with screaming, autonomic fear symptoms, and amnesia during N3 sleep.

Parasomnia during REM sleep causing acting out dreams, often violent movements, and increasing risk in older adults.

A scoring system that evaluates the difficulty of visualizing the airway, which is related to the risk of OSA.

Abnormal behaviors or experiences during sleep, including sleepwalking, sleep terrors, and REM sleep behavior disorder.

An economical test that measures airflow, chest/abdominal movements, and pulse oximetry during sleep, but with a higher risk of false negatives.