Sleep and Biological Rhythms

Flashcards covering concepts related to sleep, sleep measurement, brain waves, sleep cycles, sleep disorders, neural control of sleep, and circadian rhythms.

Sleep

A dynamic and actively produced brain state with accompanying changes to physiology.

Electroencephalograph (EEG)

A method used to measure sleep by recording brain activity.

Electromyogram (EMG)

A method used to measure sleep by recording muscle activity.

Electro-oculogram (EOG)

A method used to measure sleep by recording eye movements.

Gamma Waves

Brain wave frequency higher than 30 Hz, associated with concentrating, focusing, and learning.

Beta Waves

Brain wave frequency between 13-30 Hz, associated with most activities while awake.

Alpha Waves

Brain wave frequency between 8-12.99 Hz, associated with relaxation or sleepiness.

Theta Waves

Brain wave frequency between 4-7.99 Hz, associated with stage 1 and 2 (light) sleep.

Delta Waves

Brain wave frequency between 1-3.99 Hz, associated with stage 3 (deep) sleep.

REM sleep

Brain activity during REM sleep is associated with Dreaming.

Lucid dreaming

Dreamer is aware they are dreaming and have some control over the dream characters, narrative, and/or environment.

Sleep deprivation

Impairs cognition, increases anxiety, stroke risk, diabetes risk, depression symptoms, breast cancer risk, heart disease risk, and weight gain.

Adenosine

Primary candidate for sleep homeostasis. Sleep pressure increases with time awake, due to increases in sleep-promoting substances. Caffeine blocks adenosine receptors to reduce sleepiness

Acetylcholine

Neurotransmitter that produces activation and cortical desynchrony when neurons are stimulated.

Norepinephrine

Neurotransmitter released throughout the brain by neurons of the locus coeruleus.

Serotonin

Neurotransmitter that, when stimulated in the raphe nuclei, causes cortical arousal.

Histamine

Neurotransmitter that increases cortical activation and arousal.

Orexin

A neuropeptide secreted by the lateral hypothalamus that has excitatory effects in regions involved in arousal.

Insomnia

A sleep disorder characterized by difficulties falling asleep, staying asleep, or waking up too early, with associated problems like fatigue and impaired performance, lasting at least 3 months.

Sleep apnea

A sleep disorder in which breathing repeatedly stops and starts.

Obstructive sleep apnea (OSA)

A common form of sleep apnea that occurs when throat muscles relax and block the flow of air into the lungs.

Central sleep apnea (CSA)

A type of sleep apnea where the brain does not send proper signals to the muscles that control breathing.

Narcolepsy

A chronic hereditary autoimmune disorder characterized by excessive daytime sleepiness and sleep attacks, sometimes with cataplexy.

Parasomnias

Disruptive sleep-related disorders that can occur during arousals from REM sleep or partial arousals from Non-REM sleep.

Night terrors

Experiencing a night terror or sleep terror abruptly awakes from sleep in a terrified state. The person may appear to be awake, but is confused and unable to communicate.

Circadian rhythms

Physical and behavioral changes that follow a ~24-hour cycle and respond primarily to light and dark.