Chapters 4.1 to 4.5 Key Terms

Consciousness

our subjective awareness of ourselves and our environment (awareness of internal and external stimuli)

• awareness of internal stimuli = feeling pain, hunger, thirst, sleepiness, and being aware of our thoughts and emotions

• awareness of external stimuli = experiences such as seeing the light from the sun, feeling the warmth of a room, and hearing the voice of a friend

Sleep Patterns and Age

• Infants sleep about 16 hours a day

  • Infants spend about 50% of their sleep in REM

• Young Adults sleep about 7-9 hours

  • spend about 25% of their time in REM 

• 70 year-olds sleep only about 6 hours

  • spend about 18% of their time in REM

Effects of Drinking

• Alcohol is a depressant, so it acts like a sedative

• Alcohol slows cognitive processing

• Alcohol reduces self-awareness and self-control

• Alcohol leads to risky decision-making

• Alcohol can disrupt memory formation

Drinking and Driving

• Alcohol is a depressant, so it acts like a sedative

• Alcohol slows cognitive processing

• Alcohol reduces self-awareness and self-control (won’t be able to see a person or object fast enough)

• Alcohol leads to risky decision-making (thinking a light is still orange when it’s red)

Sleep

A state marked by relatively low levels of physical activity and reduced sensory awareness that is distinct from periods of rest that occur during wakefulness

Wakefulness

characterized by high levels of sensory awareness, thought, and behavior

Biological Rhythms

internal cycle of biological activity (recurring cyclical pattern of bodily changes)

• ex. a woman’s menstrual cycle 

• ex. circadian rhythm 

Circadian Rhythm

our biological clock; regular bodily rhythms that occur over approximately 24 hours

• ex. the sleep-wake cycle, body temperature fluctuations 

Homeostasis 

tendency to maintain a balance, or optimal level, within a biological system

Suprachiasmatic nucleus (SCN)

a pair of cell clusters in the hypothalamus that controls circadian rhythm. In response to light, it adjusts melatonin production, thus modifying our feelings of sleepiness.

Melatonin

A hormone secreted by the endocrine gland that serves as an important regulator of the sleep-wake cycle

Pinal Gland

The endocrine structure located inside the brain that releases melatonin

• melatonin release = stimulated by darkness and inhibited by light 

Sleep Regulation 

The brain’s control of switching between sleep and wakefulness, as well as coordinating this cycle with the outside world

Jet lag

A collection of symptoms brought on by travel from one time zone to another that results from the mismatch between our internal circadian cycles and our environment

• symptoms include fatigue, sluggishness, irritability, and insomnia 

Insomnia

consistent difficulty in falling or staying asleep for at least three nights a week over a month’s tim

Rotating shift work

work schedule that changes from early to late on a daily or weekly basis

• people working these are more likely to experience disruptions in circadian cycles

  • results in sleeping problems, and can lead to depression, anxiety, and persistent feelings of exhaustion and agitation 

REM rebound/sleep debt

The tendency for REM sleep to increase following REM sleep deprivation.

• Consequences = decreased levels of alertness and mental efficiency 

• Sleep deprivation = associated with depression-like symptoms, obesity, increased blood pressure, increased levels of stress hormones, and reduced immune functioning

Sleep deprivation

associated with depression-like symptoms, obesity, increased blood pressure, increased levels of stress hormones, and reduced immune functioning

sleep rebound

sleep-deprived individuals will experience shorter sleep latencies during subsequent opportunities for sleep

Why we need sleep

1. Protects = a species’ sleep pattern tends to suit its ecological needs (darkness shuts down ancestors’ hunting and gathering = safer in a cave and not wandering)

2. Restores = gives body and mind a chance to repair, rewire, and reorganize

   1. Allows you to restore resources that are expended during the day

3. Aids in memory consolidation = helps restore and rebuild our fading memories of the day’s experiences (determines if memory goes to short-term or long-term)

4. Feeds creative thinking = dreams inspire

5. Supports growth

6. Conserves energy

Beta waves

type of brain wave characteristic during wakefulness, which has a very low amplitude and a frequency of 13–30 Hz

Rapid Eye Movement (REM)

a recurring sleep stage during which dreams commonly occur. Also known as paradoxical sleep, because the muscles are relaxed (except for minor twitches) but other body systems are active.

• characterized by darting movements of the eyes under closed eyelids 

• Your EEG resembles that of someone awake

• Many physiological measures mimic being awake, BUT your muscle tone drops to almost nothing (don’t want you to act out your dreams)

Non-REM (NREM)

period of sleep outside periods of rapid eye movement (REM) sleep. It is subdivided into 3 stages distinguished from each other and from wakefulness by characteristic patterns of brain waves

• Stage 1

• Stage 2 

• Stage 3 

NREM: Stage 1

It is a transitional phase that occurs between wakefulness and sleep, the period during which we drift off to sleep (relatively easy to wake up from) 

• Slowdown in both rates of respiration and heartbeat, and a decrease in both muscle tension and core body temperature

• your EEG (recording of brain activity) is somewhat irregular and contains alpha waves and theta waves

• may have some hallucinations 

NREM: Stage 2

Deep relaxation.

• EEG shows mostly Theta waves.

  • Your EEG now includes sleep spindles and K-complexes.

    • Sleep spindles = rapid burst of higher frequency brain waves that MAY be important for learning and memory 

    • K-complexes = is a very high amplitude pattern of brain activity that MAY in some cases occur in response to environmental stimuli 

NREM: Stage 3

This is the “deepest” stage of sleep

• Your EEG includes mostly delta waves

• Individual’s heart rate and respiration slow dramatically 

• It’s difficult to be roused from Stage 3, and if you are roused, you are very groggy

Dreams

a sequence of images, emotions, and thoughts passing through a sleeping person’s mind.

Wish fulfillment theory

Proposed by Sigmund Freud, the theory that dreaming is where subconscious, unacceptable feelings can be projected. He suggested that dreams have both a surface storyline, the manifest content, and a hidden meaning, the latent content.

• NO scientific backing 

• satisfy unconscious urges or resolve unconscious conflicts.

• ex. a 9th grader has a dream about riding on a train with their math teacher (having fun/laughing together) and the train enters a dark tunnel

  • manifest = on the train with math teacher and it enters a tunnel

  • latent = it’s about sex 

Collective unconsciousness

It is a theoretical repository of information believed to be shared by everyone

• certain symbols in dreams reflected universal archetypes with meanings that are similar for all people regardless of culture or location 

• Theory created by Carl Jung

Activation-synthesis Theory

During REM sleep, the hindbrain sends random electrical impulses that activate portions of the cerebral cortex.

• The cerebral cortex tries to synthesize and make sense of these random impulses by using stored memories and current feelings.

  • Dreams are a byproduct of brain activity during REM sleep

    • Dreams may or may not have meaning

      • ex. You can dream about a party where everyone from all stages of your life are gathered together from the age you last saw them (ex. your childhood best friend at six and a work friend)

• Has SOME scientific backing 

Lucid dream

Dreams in which certain aspects of wakefulness are maintained during a dream state

• person becomes aware of the fact that they are dreaming and can control dream’s content

Hallucinations

false sensory experiences, such as seeing something in the absence of external visual stimuli.

cognitive-behavioral therapy

psychotherapy that focuses on cognitive processes and problem behaviors that is sometimes used to treat sleep disorders such as insomnia

Parasomnia

one of a group of sleep disorders characterized by unwanted, disruptive motor activity and/or experiences during sleep

• Can occur in either REM or NREM phases of sleep

  • ex. sleepwalking, restless leg syndrome, and night terrors

Sleepwalking 

sleep disorder in which the sleeper engages in relatively complex behaviors

• not responsive to attempts of communication 

• Occurs in Stage 3 (CANNOT occur during REM)

• Much more common in children than in adults

REM Sleep Behavior Disorder (RBD)

sleep disorder in which the muscle paralysis associated with the REM sleep phase does not occur; sleepers have high levels of physical activity during REM sleep, especially during disturbing dreams

• Have high levels of physical activity during REM sleep (ex. kicking, punching, scratching, yelling, etc)

Restless leg syndrome 

sleep disorder in which the sufferer has uncomfortable sensations in the legs when trying to fall asleep that are relieved by moving the legs

• relieved by deliberately moving the legs → makes it difficult to fall asleep

Night terrors

A sleep disorder in which the sleeper experiences a sense of panic and may scream or attempt to escape from the immediate environment

• doesn’t remember the nightmare

• usually occurs in children (usually they grow out of it) 

Sleep apnea

a sleep disorder defined by episodes during which breathing stops during sleep

• episodes can last 10-20 seconds or longer and are often associated with brief periods of awakening 

  • not aware of repeated disruptions BUT feel increased levels of fatigue 

• More common in overweight people and associated with loud snoring 

obstructive sleep apnea

sleep disorder defined by episodes when breathing stops during sleep as a result of blockage of the airway

central sleep apnea

sleep disorder with periods of interrupted breathing due to a disruption in signals sent from the brain that regulate breathing

continuous positive airway pressure (CPAP)

device used to treat sleep apnea; includes a mask that fits over the sleeper’s nose and mouth, which is connected to a pump that pumps air into the person’s airways, forcing them to remain open

sudden infant death syndrome (SIDS)

infant (one year old or younger) with no apparent medical condition suddenly dies during sleep

• Infants younger than 12 months appear to be at the highest risk

Narcolepsy

A sleep disorder in which the sufferer cannot resist falling asleep at inopportune times

• episodes associated with cataplexy (lack of muscle tone or muscle weakness) 

Information processing theory

Dreams help us sort out the day’s events and consolidate our memories.

• Dreams are related to current concerns, and they may help us solve real-life problems.

  • ex. if you stay up late working on math problems, you can dream about the math problems and come up with a solution

• Has SOME scientific backing

Sleep Talking

a parasomnia, or sleep-related disorder, characterized by verbalizations during sleep that are not remembered upon waking. 

• Usually, the person who has this condition talks about stuff from their day, what their anxious about, gibberish, etc

• can occur in ANY stage and is common in both adults and children