AP Psychology - Unit 5: Section 1

Consciousness

Our subjective awareness of ourselves and our environment

Hypnosis

A social interaction in which one person (the hypnotist) suggests to another (the subject) that certain perceptions, feelings, thoughts, or behaviors will spontaneously occur

Posthypnotic suggestions

A suggestion (made during a hypnosis session) to be carried out after the subject is no longer hypnotized

Used by some clinicians to help control undesired symptoms and behaviors

Have also helped alleviate headaches, asthma, and stress-related anxiety and skin disorders

Dissociation

A split in consciousness, which allows some thoughts and behaviors to occur simultaneously with others

Sleep

A periodic, natural loss of consciousness

As distinct from unconsciousness resulting from a coma, general anesthesia, or hibernation

Circadian rhythm (sleep/wake cycle)

Our internal biological clock; Regular body rhythms that occur on a 24-hour cycle

Ex. Temperature, wakefulness

They impact our sleep-wake cycle, temperature, hormonal, and digestive cycles as well

REM sleep

A recurring sleep stage during which vivid dreams commonly occur

Rapid Eye Movement sleep, AKA “paradoxical sleep” (because the muscles are relaxed, except for minor twitches, but other body systems are active)

Alpha waves

The relatively slow brain waves of a relaxed, awake state

NREM sleep

Encompasses all sleep stages except for REM sleep

Non-Rapid Eye Movement sleep

Hallucinations

False sensory experiences

Ex. Seeing something in the absence of an external visual stimulus

Hypnagogic sensations

Bizarre experiences while transitioning to sleep

Ex. Jerking, feeling of falling, feeling of floating weightlessly

Delta waves

The large, slow brain waves associated with the deep sleep of NREM-3

Suprachiasmatic nucleus (SCN)

A pair of cell clusters in the hypothalamus that controls circadian rhythm

In response to light, it causes the pineal gland to decrease production of the sleep-inducing hormone melatonin in the morning and to increase it in the evening, thus modifying our feelings of sleepiness

Light striking the retina signals it to supress the pineal gland’s production of melatonin; With decreased/absence of light, it quiets down, allowing the pineal gland to release melatonin into the bloodstream

Melatonin

Sleep-inducing hormone released by the pineal gland

Why we sleep

• Protection: In an evolutionary perspective, sleep reduces vulnerability to predators

• Health: Helps restore the immune system and repair brain tissue

  • Allows resting neurons time to repair themselves and prune/weaken unused connections

• Memory: Helps restore and rebuild our fading memories of the day’s experiences (memory consolidation)

• Creativity: Dreams can inspire noteworthy artistic and scientific achievements; Boosts thinking and learning

• Growth: During slow-wave sleep, the pituitary gland releases human growth hormone, which is necessary for muscle development

NREM Stage 1 (stage 1 sleep)

The stage of NREM sleep where you may experience hypnagogic sensations (fantastic images resembling hallucinations, sensation of falling or floating weightlessly), which can later be incorporated into your memories

The initial stage of NREM sleep, which is characterized by low-amplitude brain waves (4-6 Hz) of irregular frequency, a slow heart rate, and reduced muscle tension

The transitional phase from wakefulness to sleep; Light sleep with slow eye movements, alpha waves, and possible hypnic (muscle) jerks and dream-like sensations, easy to awaken from

NREM Stage 2 (stage 2 sleep)

The stage of NREM sleep where you relax more deeply with periodic sleep spindles (bursts of rapid, rhythmic brain-wave activity and K-complexes)

A stage of NREM sleep that is defined by regular bursts of waves of about 15 Hz that progressively increase and then decrease in amplitude; Half of your nights sleep

Deep relaxation phase; Heart rate and body temperature drop, characterized by theta waves interrupted by sudden bursts of activity called sleep spindles, which are important for learning

NREM Stage 3 (stage 3 sleep)

During this slow wave sleep, which lasts for about 30 minutes your brain emits slow delta waves; deep sleep; where somnambulism (sleepwalking) is most likely to occur

The deepest, more restorative sleep phase; Marked by slow, high-amplitude delta waves, crucial for physical restoration, growth, and immune function

Hard to awaken during this stage

EEG

An amplified recording of the waves of electrical activity sweeping across the brain’s surface

These waves are measured by electrodes placed on the scalp

From this, researchers were able to see that a sleeper’s eyes moved rapidly from left to right while emitting rapid, saw-toothed brain waves

Consolidation theory

The theory that sleep aids in memory consolidation; Sleep helps restore and rebuild the experiences and memories of our day

Activation synthesis theory

The theory that dreams reflect inputs from brain activation originating in the pons, which the forebrain then attempts to weave into a story

The theory that explains dreams as the brain’s attempt to create a coherent story (synthesis) from random neural signals (activation) generated in the brainstem during REM sleep, interpreting these signals using existing memories and emotions, thus making sense of physiological processes

Altered states of consciousness

• Daydreaming

• Sleeping

• Drug-induced hallucinating

• Meditating

Sleep spindles

Bursts of rapid, rhythmic brain-wave activity and K-complexes in NREM stage 2

Physiological events occurring during REM sleep

• Heart rate rises: Breathing becomes rapid and irregular

• Muscle paralysis occurs (except for an occasional twitch)