4.) 1.5 Sleep (#32-37)

#32-37

consciousness

• the concept of our subjective awareness of ourselves and our environment.

• this concept was scientifically studied in the early 20th century, but abandoned by 1960. However, in the 1960s, it resurfaced as an important concept.

circadian rhythm

• our biological clock that regulates our mood, temperature, and arousal through a 24-hour cycle.

• As morning nears, body temperature RISES, then peaks during the day, dips for a time in the early afternoon, and begins to DROP in the evening.

Jet lag

when a circadian rhythm can be thrown off by a change of time zones, certain work schedules, and can also be varied by age and individual (night owls vs. morning birds).

NREM sleep vs REM sleep

• NREM sleep: no rapid eye movement

• REM sleep: rapid eye movement

Name the stages of consciousness in order

1. Awake and alert

2. Awake and relaxed

3. NREM-1

4. NREM-2

5. NREM-3

6. REM

1. Awake & Alert

• Normal waking consciousness

• EEG: Beta waves

2. Awake and relaxed

• the transition state between being fully awake and falling asleep

• EEG: Alpha waves

3. NREM-1

• light sleep and can be easily awaken

• can experience hallucinations (sensory experiences that occur without a sensory stimulus) and hypnagogic sensations (bizarre experiences such as jerking with a sensation of falling)

• EEG: Decrease in alpha waves (irregular, medium frequency); presence of Theta waves (low frequency, high amplitude)

4. NREM-2

• half of one’s sleep time; considered light sleep, but deeper than NREM-1 sleep, and can get easily awakened.

• EEG: Theta waves with Sleep Spindles (bursts of rapid, rhythmic brain-wave activity that aid memory processing) and k-complexes (random, tall bursts of activity)

5. NREM-3

• deep sleep

• EEG: slow wave, 30 min Delta waves (large, slow waves associated with deep sleep)

6. REM

body relaxed, as if paralyzed, but brain as active as if it was awake (paradoxal sleep)

EEG: Beta waves

activation synthesis

• REM sleep triggers neural activity that evokes random visual memories, which our sleeping brain weaves into stories.

• (our cerebral cortex is trying to interpret random electrical activity we have while sleeping. It is the brain’s efforts to make sense our of meaningless patterns of firing in the brain as we sleep.

memory consolidation

• the process by which short-term memories are transformed into long-term memories during sleep or rest periods.

insomnia

a sleep disorder that causes recurring problems in falling or staying asleep

narcolepsy

a sleep disorder characterized by uncontrollable “sleep attacks” and may immediately cause one directly into REM sleep often at inappropriate times.

sleep apnea

a sleep disorder characterized by temporary cessations of breathing during sleep and repeated momentary awakenings

REM sleep behavior disorder

a sleep disorder in which normal REM paralysis does not occur. Instead, twitching, talking, or even kicking or punching may occur, often acting out one’s dreams.

somnambulism

a sleep disorder characterized by sleep walking; repeated episodes of complex motor behavior, such as walking while asleep.