Consciousness 4.3 [HY] Flashcards
Reticular formation (reticular activation system)
- reticular activation system
- a neural structure located in the brainstem, to keep the cortex awake and alert
- disruption results in coma
What do EEG’s do?
records an average of the electrical patterns within different portions of the
brain.
Beta waves
- have a high frequency and occur when the person is alert or attending to a mental task that requires concentration.
- occur when neurons are randomly firing
Alpha waves
- when we are awake but relaxing with our eyes closed, and are somewhat slower than beta waves
- more synchronized than beta waves.
Stage 1 (NREM1)
- As soon as you doze off
- Theta Waves
- waveforms with
slower frequencies and higher voltages. - Resembles meditation
Stage 2 (NREM2)
- Theta Waves
- Sleep spindles: bursts of high frequency waves
- K complexes: singular high-amplitude waves
- mental experience starts to shift to a dreamlike state
Stage 3 (NREM3)
- Slow-wave sleep (SWS)
- Delta Waves: low-frequency, high-voltage sleep waves
- SWS is associated with cognitive recovery and memory consolidation, as well as increased growth hormone release.
Rapid eye movement (REM) sleep
- Interspersed between cycles of the NREM stages
- arousal levels reach that of wakefulness, but the muscles are paralyzed
- paradoxical sleep because one’s heart rate, breathing patterns, and EEG mimic wakefulness
- Procedural & Declarative (conscious memory of particular facts) memory Consolidation
- 75% of dreaming occurs during REM
- REM dreams tend to be longer and more vivid than those experienced during
NREM sleep
Order of Brain waves MNEUMONIC
BAT-D: Beta, Alpha, Theta, Delta
Cortisol and wakefulness
- produced in the adrenal cortex
- levels slowly increase during early morning
- increasing light causes the release of corticotropin-releasing factor (CRF) from the hypothalamus
- CRF causes release of adrenocorticotropic hormone (ACTH) from the anterior pituitary, which stimulates cortisol release.
Activation–synthesis theory
- dreams are caused by widespread, random activation of neural circuitry.
- This activation can mimic incoming sensory information, and may also consist of
pieces of stored memories, current and previous desires, met and unmet needs, and other experiences.
Problem solving dream theory
- Dreams are a way
to solve problems while you are sleeping - Dreams are untethered by the rules of the real world, and thus allow interpretation of obstacles differently than
during waking hours.
Cognitive process dream theory
- dreams are merely the sleeping counterpart of stream-of-consciousness
Neurocognitive models of dreaming seek to do?
seek to unify biological
and psychological perspectives on dreaming by correlating the subjective, cognitive experience of dreaming with measurable physiological changes
Dyssomnias
- disorders that make it difficult to fall asleep, stay asleep, or avoid sleep.
- Include insomnia, narcolepsy, and sleep apnea.
Parasomnias
- abnormal movements or behaviors during sleep
- Include night terrors and sleepwalking
Cataplexy
a loss of muscle control and sudden intrusion of REM sleep during waking hours,
usually caused by an emotional trigger
Hypnagogic
hallucinations when going to sleep
Hypnopompic
hallucinations when awakening
Hallucination Mneumonic
Hypnagogic hallucinations occur when one is going to bed. Hypnopompic hallucinations
occur when one is popping up out of bed.
REM rebound
- an earlier onset and greater duration of REM sleep compared to normal
- Exhibited by people who are
permitted to sleep normally after sleep deprivation
