Sleep

Endogenous

Generated from within

Endogenous Circannual Rhythm

Yearly

Endogenous Circadian Rhythm

Daily

Zeitgeber

Stimulus that resets the circadian rhythm

Jet Lag

Disruption of circadian rhythms due to crossing time zones

Cortisol

Stress hormone damaging neurons in the hippocampus

SUPRACHIASMATIC NUCLEUS

Main driver of sleep and body temperature rhythms

Retinohypothalamic path

Optic nerve branch altering the SCN's settings

Melatonin

Hormone affecting sleepiness in diurnal and nocturnal animals

Coma

Extended period of unconsciousness

Vegetative State

Alternates between sleep and moderate arousal

Brain Death

No brain activity or response to stimuli

STAGE 2 SLEEP

Includes K-complex and Sleep Spindles

Paradoxical Sleep

Deep and light sleep, used in species lacking eye movements

Reticular Formation

Structure extending from medulla into forebrain

GABA

Inhibitory neurotransmitter promoting slow-wave sleep

Locus Coeruleus

Structure emitting impulses related to emotional arousal

Histamine

Neurotransmitter enhancing arousal and alertness

Orexin/Hypocretin

Enhances wakefulness and activity

Somnambulism

Sleepwalking

Lucid Dreaming

Being aware of dreaming while asleep

PONS-GENICULATE-OCCIPITAL (PGO)

Associated with REM sleep

Insomnia

Inadequate sleep

Sleep Apnea

Impaired breathing during sleep

Narcolepsy

Frequent daytime sleepiness with specific symptoms

Periodic Limb Movement Disorder

Involuntary limb movements during sleep

REM Behavior Disorder

Moving around during REM sleep

Night Terrors

Intense anxiety experiences during sleep

FUNCTIONS OF SLEEP

Energy conservation and improved memory

PHENOMENON OF LONG-TERM POTENTIATION

Strengthening synaptic connections with new experiences

Homeostasis

Regulation of body variables within a fixed range

Set Point

Value the body works to maintain

Negative Feedback

Processes reducing discrepancies from the set point

Allostasis

Achieving stability through internal changes to meet external demands

Basal Metabolism

Energy used to maintain body temperature at rest

Ectothermic

Depending on external heat sources

Endothermic

Generating body heat internally

Preoptic Area/Anterior Hypothalamus (POA/AH)

Controls autonomic responses

Fever

Represents an increased set point for body temperature