Competency 17: Rest and Sleep

What is sleep?

A state of altered consciousness that allows the body and brain to rest, recover, and perform essential physiological functions.

What is rest?

A state of reduced physical and mental activity that promotes relaxation and a feeling of refreshment without necessarily falling asleep.

What is a circadian rhythm?

An internal biological rhythm that repeats approximately every 24 hours and regulates sleep, wakefulness, and other body functions.

What is another name for circadian rhythm?

Diurnal rhythm.

How does the circadian rhythm influence sleep?

It helps the body feel sleepy at night and alert during the day.

What environmental factors help synchronize the circadian rhythm?

Light and temperature.

What is sleep-wake homeostasis?

The biological mechanism that increases the body's need for sleep the longer a person remains awake.

What are the two major biological mechanisms that regulate sleep?

Circadian rhythm and sleep-wake homeostasis.

How does sleep-wake homeostasis respond to sleep deprivation?

It increases sleep pressure, making the person more likely to fall asleep and experience deeper sleep.

What factors can disrupt the normal sleep-wake cycle?

Stress, caffeine, medications, light exposure, shift work, environmental noise, and irregular sleep schedules.

What is melatonin?

A natural hormone produced by the pineal gland that helps prepare the body for sleep.

When does melatonin production normally increase?

During darkness, especially at night.

How can bright light at night affect sleep?

It can disrupt circadian signaling and suppress melatonin production, making sleep more difficult.

Why are night-shift workers at risk for sleep disturbances?

Their work schedules conflict with the body's natural circadian rhythm.

What health problems are associated with disrupted circadian rhythms in shift workers?

Excessive daytime sleepiness, fatigue, obesity, diabetes, and cardiovascular disease.

What are the four major regions of the brain?

Cerebrum, cerebellum, diencephalon, and brainstem.

What is the function of the cerebral cortex related to sleep?

It processes sensory information and helps transfer information from short-term to long-term memory.

What structures make up the diencephalon?

Thalamus, hypothalamus, and pineal gland.

What is the hypothalamus's role in sleep?

It regulates sleep and arousal through groups of nerve cells and hormonal signaling.

What is the suprachiasmatic nucleus (SCN)?

A structure within the hypothalamus that regulates circadian rhythms using light information from the eyes.

What can happen if the SCN is damaged?

The person may experience irregular sleep-wake cycles.

What is the brainstem's role in sleep?

It helps control transitions between wakefulness and sleep and participates in REM sleep regulation.

Which brainstem structures influence REM sleep?

The pons and medulla oblongata.

Why are skeletal muscles temporarily inhibited during REM sleep?

To prevent the person from physically acting out dreams.

What is the thalamus's role during most stages of sleep?

It helps block external sensory distractions.

How does the thalamus function differently during REM sleep?

It transmits sensory information that contributes to dream experiences.

What is the function of the pineal gland?

It produces melatonin.

What is gamma-aminobutyric acid (GABA)?

An inhibitory neurotransmitter that reduces activity in brain arousal centers and promotes sleep.

How does GABA contribute to sleep?

It decreases neuronal activity involved in wakefulness.

What is the relationship between the brain and memory during sleep?

Sleep supports memory consolidation and the formation of pathways needed for learning.

What are the two main types of sleep?

Non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep.

What is NREM sleep?

Sleep without rapid eye movements, consisting of progressively deeper stages.

What is REM sleep?

A stage associated with vivid dreaming, rapid eye movements, increased brain activity, and reduced skeletal muscle tone.

How many times does a person typically cycle through NREM and REM sleep each night?

Approximately four to six times.

What is an electroencephalogram (EEG)?

A test that records electrical activity in the brain.

What characteristics are used to identify sleep stages?

Brain waves, eye movements, muscle activity, and physiological changes.

What are alpha waves associated with?

Relaxed wakefulness, particularly when the eyes are closed.

What are beta waves associated with?

Alertness and active mental engagement.

What is NREM stage 1 (N1)?

The lightest stage of sleep, during which a person transitions from wakefulness to sleep.

What happens to body activity during NREM stage 1?

Brain activity slows, eye and body movements decrease, and occasional muscle twitching may occur.

How long does stage 1 typically last?

Approximately 1-5 minutes.

What percentage of total sleep does stage 1 account for?

Approximately 5%.

What is NREM stage 2 (N2)?

A deeper stage of sleep characterized by sleep spindles and K-complexes.

What are sleep spindles and K-complexes associated with?

Maintaining sleep and supporting memory consolidation.

What happens to heart rate and body temperature during stage 2?

Both decrease.

What percentage of total sleep occurs in stage 2?

Approximately 50%.

What is NREM stage 3 (N3)?

The deepest stage of NREM sleep, characterized by slow delta brain waves.

What are delta waves?

Slow-frequency, high-amplitude brain waves associated with deep sleep.

What important physical processes occur during stage 3?

Immune system strengthening and repair of muscles, tissues, and bones.

What may happen if a person is awakened during stage 3?

Mental cloudiness or grogginess lasting approximately 30-60 minutes.

What happens to pulse and respiratory rate during deep NREM sleep?

They decrease to relatively low levels.

When does the first REM period typically begin?

Approximately 90 minutes after falling asleep.

What happens to breathing and heart rate during REM sleep?

Breathing becomes irregular, and heart rate may increase.

What is muscle atonia during REM sleep?

Temporary loss of skeletal muscle tone.

What percentage of an adult's sleep is typically REM sleep?

Approximately 20-25%.

How do REM periods change throughout the night?

They generally become longer as the night progresses.

How do stage 3 sleep and REM sleep differ?

Stage 3 emphasizes deep physical restoration, while REM is associated with vivid dreaming and active brain processes.

How does aging affect NREM stage 3 sleep?

The amount of deep stage 3 sleep generally decreases.

What changes in sleep are commonly observed in older adults?

More frequent awakenings, lighter sleep, and longer time needed to fall asleep.

What is a sleep cycle?

A recurring sequence of NREM and REM sleep stages throughout the night.

Why is sleep essential for physical health?

It supports tissue repair, immune function, healing, and normal metabolic processes.

How does sleep benefit mental health?

It supports mood regulation, concentration, memory, and emotional well-being.

How does adequate sleep affect reaction time and coordination?

It improves reaction time, hand-eye coordination, and physical performance.

How does sleep support the immune system?

It strengthens immune defenses and supports recovery from illness.

How does sleep affect the body's ability to learn?

It helps consolidate memories and retain newly learned information.

What is ghrelin?

A hormone that stimulates hunger.

What is leptin?

A hormone that signals fullness and helps decrease hunger.

How can inadequate sleep contribute to weight gain?

It can increase hunger signals, reduce fullness signals, and alter eating behaviors.

What is cortisol?

A stress hormone that affects metabolism, blood glucose, and the body's response to stress.

How can increased cortisol affect blood glucose?

It can contribute to insulin resistance and elevated blood glucose levels.

Why is adequate sleep important for clients with type 2 diabetes?

It supports blood glucose regulation and may improve metabolic health.

How does quiet rest benefit someone who cannot sleep?

It allows physical relaxation, reduces stress, and can improve mood and mental clarity.

How many hours of sleep are recommended for newborns from birth to 3 months?

Approximately 14-17 hours per day.

How many hours of sleep are recommended for infants ages 4-12 months?

Approximately 12-16 hours per day, including naps.

How many hours of sleep are recommended for toddlers ages 1-2 years?

Approximately 11-14 hours per day, including naps.

How many hours of sleep are recommended for preschoolers ages 3-5 years?

Approximately 10-13 hours per day, including naps.

How many hours of sleep are recommended for school-age children ages 6-12 years?

Approximately 9-12 hours per day.

How many hours of sleep are recommended for adolescents?

Approximately 8-10 hours per day.

How much sleep do most adults ages 18-60 need?

At least 7 hours per night.

How much sleep is recommended for adults ages 61-64?

Approximately 7-9 hours per night.

How much sleep is recommended for adults ages 65 and older?

Approximately 7-8 hours per night.

How are newborn sleep patterns different from adult sleep patterns?

Newborns sleep in multiple shorter periods throughout the day and night.

What percentage of sleep is REM sleep in infants younger than approximately 3 months?

Approximately 50%.

How do infant sleep patterns typically change around 5-6 months?

Infants begin sleeping for longer periods at night while still taking daytime naps.

When do children's sleep patterns begin progressing toward adult patterns?

After approximately 1 year of age.

What is sleep deprivation?

Failure to obtain enough sleep or adequate sleep quality to meet the body's biological needs.

What is total sleep deprivation?

Losing an entire night's sleep or remaining awake for a prolonged period.

What is partial sleep deprivation?

Sleeping fewer hours than the body requires.

What is chronic sleep deprivation?

Repeatedly obtaining insufficient sleep over an extended period.

What is selective sleep deprivation?

Deliberately preventing or interrupting a particular stage of sleep.

How does sleep deprivation affect judgment?

It impairs decision-making and increases the likelihood of errors.

How does sleep deprivation affect response time?

It slows reactions and increases accident risk.

What neurological problems may be triggered or worsened by sleep deprivation?

Migraines, tension headaches, and seizures in susceptible individuals.

What psychological effects can sleep deprivation cause?

Irritability, mood swings, anxiety, depressive symptoms, and impaired concentration.

What long-term health problems are associated with inadequate sleep?

Obesity, diabetes, hypertension, cardiovascular disease, and depression.

Why is sleep deprivation especially dangerous when driving?

Drowsiness reduces alertness, judgment, coordination, and reaction time.

What common circumstances can cause sleep deprivation?

Stress, illness, caring for a newborn, medications, shift work, sleep disorders, and excessive workload.

Why might a client fail to recognize their own sleep deprivation?

The client may not fully notice the decline in cognitive performance.

How can hospital routines contribute to sleep deprivation?

Repeated assessments, procedures, alarms, medication administration, and environmental disturbances interrupt sleep.

What is the initial approach to managing sleep deprivation?

Identify the underlying cause and implement sleep-promoting lifestyle and environmental changes.