1 / 17

The Biology of Sleep

The Biology of Sleep. How Do We Research Sleep?. EEGs Monitor brain waves Wake people up in the midst of a sleep cycle or dream Eugene Aserinsky – discovered REM sleep Works with Nathaniel Kleitman William Dement – Father of sleep medicine; World’s first sleep laboratory. Body Rhythms .

will
Download Presentation

The Biology of Sleep

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Biology of Sleep

  2. How Do We Research Sleep? • EEGs • Monitor brain waves • Wake people up in the midst of a sleep cycle or dream • Eugene Aserinsky – discovered REM sleep • Works with Nathaniel Kleitman • William Dement – Father of sleep medicine; World’s first sleep laboratory

  3. Body Rhythms • Circadian Rhythms (about a day) • Body rhythms that occur on a 24 hour cycle • Biological clock • Sleep-Awake cycle • Ultradian Rhythms • Occur more than once a day • Sleep stages

  4. Sleep and the Brain • Suprachiasmatic Nucleus (SCN) • Cluster of neurons in the hypothalamus • Receives info about day and night cycles from the retina • Depending on cycles detected by eye, it releases neurotransmitters that control body temperature, metabolism, blood pressure, hormone levels, hunger • Works with pineal gland • Adenosine • Chemical that triggers sleepiness (high levels = sleepiness) • Melatonin • Levels rise as it gets darker (makes us ready for sleep!)

  5. Other Brain Parts and Sleep • Pons: Involved in REM sleep • Sends signals to shut off spinal cord • Thalamus: helps us tune out sensory signals during sleep

  6. Other Facts About Sleep… • Bright light at night delays sleep • Thinking is sharpest and memory is most accurate when we are at our daily circadian peak • After pulling an all nighter you may get a second wind after your normal wake-up time arrives

  7. Sleep Stages (Every 90 minutes) • Awake/Relaxed • Alpha waves: slow brain waves • Beta waves are alert, waking waves

  8. Stage 1-2: Light Sleep • Stage 1: • Irregular brain waves • Slowed breathing • Hypnagogic Sensations: • Similar to hallucinations • Floating weightlessly, falling, etc • Stage 2 (after 10-15 minutes): • Sleep spindles – bursts of rapid, rhythmic brain wave activity • Could be awakened without too much difficulty • Spend 50% of the night here Sleep talking usually occurs in these stages!

  9. Stage 3-4: Deep Sleep • Stage 3: • Delta waves: large, slow waves • Stage 4: • More delta waves • Deep sleep • Hard to waken you during these stages (disoriented) • Sleep walking usually occurs here

  10. REM – Rapid Eye Movement • Heart rate rises, breathing becomes rapid and irregular, eyes dart around • Brainwaves resemble waking brain waves • However, brainstem blocks the messages from the motor cortex (although it is active) • Paradoxical Sleep • 20% of the night is spent here

  11. Cycle Repeats About Every 90 Minutes • With each 90-minute cycle, stage 4 sleep decreases and the duration of REM sleep increases

  12. Why Do We Need Sleep? • Sleep protects • A species sleep patterns suits its ecological niche • Animals with the greatest need to graze and the least ability to hide tend to sleep less • Helps us recuperate, restore, and repair brain tissue • Helps us restore and rebuild our fading memories • Helps creativity • May play a role in the growth process (pituitary gland releases growth hormone)

  13. Sleep Disorders • Insomnia • Apnea • Nightmares v Night terrors • Narcolepsy

More Related