Lecture on Sleep & Dreams + Chapter 5 "Sleeping and Dreaming"

Altered State of Conciousness

Form of experience that differs greatly from usual subjective experiences of the world and the mind.

Hypnagogic State

Pre-sleep conciousness

Hypnopompic State

Post-sleep consiousness

Hypnic Jerk

Sudden jerk or feeling of dropping you get when you’re asleep

Circadian Rhythm

Naturally occurring 24-hour cycle

Beta Waves, Alpha

High frequency activity, Low frequncy activity

REM Sleep

Stage of sleep characterized by rapid eye movements and a high level of brain activity

pulse quickens, blood pressure rises, telltale signs of sexual arousal. Key dreaming state

Electroculograph (EOG)

an instrument that measures eye movements during sleep

5 Stages of sleep

1. Theta Waves (lower than alpha)

2. Short bursts of activity (sleep spindles and k complexes). Sleeper is harder to wake.

3. 3+4. Slow-wave sleep. Delta Waves

4. REM Sleep

Insomnia (3 Types)

Difficulty falling/staying asleep.

1. Self-induced — caused by lifestyle choice like late shift

2. Secondary Insomnia — caused by mental health conditions

3. Primary Insomnia — Caused by other conditions

Sleep Apnea

disorder in which the person stops breathing for brief periods while asleep

Narcolepsy

Sudden sleep attacks/sleepiness while awake

Sleep Paralysis

Experience of waking up unable to move. Often happens as one wakes from REM sleep.

Sleep/Night Terrors

Abrupt awakenings with panic and intense emotional arousal.

5 major characteristics of dream consciousness

1. We intensely feel emotion
2. Dream thought is illogical
3. Sensation is fully formed and meaningful
4. Dreaming occurs with uncritical acceptance
5. We have difficulty remembering

Freud’s take on dreams

Dreams are confusing and obscure be design and reflect our deep secrets/suppressed thoughts.

Manifest Content

Apparent topic or superficial meaning of dreams (Freud)

Latent Content

True underlying meaning of dreams

Activation-Synthesis Model

theory that dreams are produced when the brain attempts to make sense of random neural activity that occurs during sleep

Neurocognitive Theory of Dream

Dreaming enables by default network (network of brain regions active when a person is daydreaming/not focused/at rest)

Threat-simulation theory of dreams

Purpose of dreams is to simulate threatening situations to practice getting out.

Why are dreams uncoordinated/unplanned/tend to ramble?

Prefrontal cortex, responsible for planning, is not as active during REM sleep.

Active areas of brain while sleeping (visual, motor)

Area of brain responsible for visual perception not as active, but areas of visual association in occipital lobe are.

Motor cortex is active, but spinal neurons inhibit expression hence why we don’t move everywhere.

Lucid Dreaming

Dreamer is conscious of the fact their dreaming while dreaming

Sleep

period of physical inactivity happening at regular, repeating intervals.

Adenosine

Chemical that builds up in your brain throughout the day that makes you sleepy. And then when you sleep and it reaches a low level, you wake up. Caffeine blocks adenosine receptors.

3 purposes of sleep

conservation - sleeping conserves energy by lowering body temp

restoration - sleep repairs cells in your body, small animals sleep for longer bc they have faster metabolisms and do more damage to cells

data analysis - your brain makes sense of daytime information and analyzes it before sending it to long-term storage

memory consolidation

memories stored temporarily in the hippocampus and then sent to the cortex for long term storage. 

Non-24 sleep wake disorder

A condition where a person’s internal clock is not entrained to the 24-hour day, causing their sleep time to shift later daily

Chronotype

preferred time of day at which everyones 24 hour period of wake and sleep begins and ends. Age is an important determinant. 

Sleep enhancing learning

Performance jumps dramatically right after sleep in motor learning studies.

What causes muscle paralysis during REM

The pons blocks signals from brain to spinal cord.

What brain regions are activated during REM

Visual, emotional, and motor areas

Which regions are deactivated during REM?

Frontal reasoning and logic regions

Most common emotions in dreams

anxiety and fear

REM Behavior Disorder (RBD)

A condition where the pons fails to paralyze muscles, leading people to physically act out dreams