Sleep Flashcards
The Master body clock for sleep wake schedule
SUPRACHIASMATIC NUCLEUS OF HYPOTHALAMUS
Stages of Sleep
Stage I → drowsy; will startle awake
Stage II → light sleep
Stage III and IV → slow wave/deep sleep: regenerative sleep: body is making mRNA and NT’s for next day
REM (Stage V) → rapid eye movements, restores your psyche
- Dreaming
- No memories of dream process formed
- Cognitive cortex off line
- Muscle paralysis (atonia) except rapid eye movements
- IMPORTANT FOR LEARNING
Sleep in Aging
- longer sleep latency (longer time to fall asleep)
- decreased total sleep time
- decreased slow wave/regenerative sleep
- increased fragmentation: difficulty keeping sleep consolidated into one nocturnal period.
- advanced sleep phase: tendency to go to sleep earlier and wake up earlier
Hormone that regulates fat storage
LEPTIN
- Counteracts feeding stimulants, and promotes appetite suppression
- leptin is regulated in part by how much sleep we get (more sleep, more leptin release)
Hormone that Stimulates Appetite/Feeding
GHRELIN
Process S
- Building sleep debt
- How many hours you’ve been awake
Process C
- Day – night cycle
- Clock-dependent alertness
- Can trick it: Light cues the body to stay awake
- TIMING OF SLEEP IS DETERMINED BY WAKE-UP TIME
Retino-hypothalamic Pathway
- Receptor = retinal ganglion cells
- Secretes melatonin
- Connects to Suprachiasmatic nucleus
- Aligns brain clock to day-night cycle
(Process C = clock dependent alertness)
Melatonin
- Onset of melatonin secretion is 8-10 hours post wake-up
- suppresses the SCN (clock dependent alertness) allowing us to manifest our sleep debt and fall asleep
Narcolepsy (defined by clinical tetrad)
Serious, chronic neurological disorder characterized by:
- excessive sleepiness
- sleep paralysis
- hypnogogic hallucination: transitional state to and from sleep
- cataplexy: linking emotions to weakness
- fragmentation of sleep
Due to deficiency in the neurotransmitter HYPOCRETIN
REM Sleep Behavioral Disorder
- Failure of normal REM atonia
- Dream enactment behaviors
- Potential nocturnal injury
- Males > females
- > age 50