AP Psychology - Unit 1.5 States of Consciousness (Sleep)

Consciousness

refers to an individual’s awareness of themself and the environment

includes how aware a person is to their;

• thoughts

• emotions

• behavior

• what is happening around them

Wakefulness

• a state of consciousness where an individual is awake and is able to notice what’s around them and respond to it

Sleep

• a state of consciousness where the body is resting and an individual is not fully aware of their surroundings

• the mind is still active 

Conscious

• a level of consciousness that involves full awareness of thoughts, feelings, and surroundings during wakefulness

Preconscious

• a level of consciousness that contains accessible information that is not currently in awareness, but easily retrievable 

• example: remembering a friend’s birthday on command 

Unconscious

• a level of consciousness that holds thoughts and desires that influence an individual’s behavior

• the person is not consciously aware of these thoughts

• example: repressed childhood memories affecting adult behavior

Nonconscious

• a level of consciousness that involves autonomic functions and processes that don’t require conscious awareness 

• example: heart rate, breathing, and digestion

Circadian Rhythm

• an internal process that regulates the sleep and wakefulness cycle over 24 hours 

• helps determine when an individual will feel awake and when they feel will sleepy

• controls a variety of biological functions such as sleep patterns, hormone release (melatonin), body temperature, and blood pressure

• can be disturbed (ex: jet lag)

Frequency

• the number of electric waves per second

Amplitude

• the size of a wave

• shows how strong the signal is 

Beta Waves

• fast in frequency

• low in amplitude

• occur when we are alert/awake and during REM sleep

Alpha Waves

• slower than beta waves

• higher amplitude 

• present when we are relaxed, but also awake and present during stage 1 of sleep

Theta Waves

• even slower in frequency

• greater amplitude than alpha waves

• primarily appear during stage 2 of sleep (sometimes stage 1)

Delta Waves

• slowest frequency

• highest amplitude

• most prevalent during stage 3 of sleep (deep sleep)

Stage 1 of Sleep

• lasts 5-10 minutes

• lightest stage of sleep

• body starts to relax

• heart rate slows

• alpha waves and theta waves are present

• person may experience hypnagogic sensations

Hypnagogic Sensations

• brief, dream-like experiences that feel real

• example: feeling like you’re falling

Stage 2 of Sleep

• lasts 10-20 minutes

• transitional phase of sleep

• brain activity continues to slow (less frequency)

• theta waves appear along with sleep spindles and K-complexes

K-Complexes and Sleep Spindles

• short bursts of neural activity

• help protect an individual from easily waking up

Stage 3 of Sleep

• lasts at least 30 minutes

• one of the deepest stages of sleep

• dominated by delta waves

• the body repairs itself and growth hormones are released

• somnambulism commonly occurs during this stage

REM Sleep

• REM = Rapid Eye Movement

• last stage of sleep

• lasts 5-60 minutes

• beta waves are present

• external muscles are paralyzed

• internal muscles/structures are active

• individuals experience dreams or nightmares

REM Deprivation

occurs when a person does not get enough REM sleep

causes;

• poor memory

• lack of focus/concentration

• mood swings

• irritability

• heightened emotional sensitivity 

REM Rebound

• the phenomenon where a person enters REM sleep more quickly and spends more time in REM to compensate for REM deprivation

Sleep Disorders

• problems that regularly affect a person’s ability to fall asleep, stay asleep, or get good-quality asleep

• impacts an individual’s mental state and physical performance

Insomnia

a person has trouble falling asleep and/or staying asleep

can be caused by multiple factors such as;

• stress

• pain

• medication

• irregular sleep schedule

Narcolepsy

• a disorder where a person has difficulty sleeping at night, but will uncontrollably fall asleep during waking hours

REM Sleep Behavior Disorder

• a condition where a person acts out their dreams during REM sleep

• external muscles are not paralyzed

• produces a risk for self-injury 

Sleep Apnea

• a disorder where breathing stops and starts repeatedly during the night

• individuals with this condition are inclined to snore loudly and frequently wake up throughout the night

Somnambulism

• referred to as sleep walking

• a disorder where a person walks, talks, or performs other activities while asleep

• individuals with this condition typically have no memory of the event

Sleep Terrors/ Night Terrors

• occur when a person suddenly awakens throughout the night in a fit of extreme fear or panic

• mostly common in children 

Activation-Synthesis Theory

• suggests that dreams are the brain’s attempt to make sense of random neural activity during REM sleep

Consolidation Theory

• proposes that dreaming is a part of the process of consolidating memories

• information from short-term memory is transferred to long-term memory

• dreams reflect the processing of things that a person learned or experienced throughout the day

Restoration Theory

• believes that sleep allows the body and brain to recover and restore energy and resources that were used during the day

Why Do We Sleep?

Sleep…

• helps to restore health and efficiency

• supports growth and conserves energy

• helps consolidate information

• helps replay and process stressors from the day