VCE Psychology Unit 4: Sleep and Consciousness

Vocabulary flashcards defining key psychological terms, physiological measurement tools, biological mechanisms, and sleep cycle concepts covered in Chapter 6.

Consciousness

The level of awareness an individual has of their thoughts, feelings, perceptions, and existence.

Psychological construct

An agreed upon description and understanding of psychological phenomena that cannot be overtly measured or observed.

Normal waking consciousness (NWC)

A state of consciousness in which an individual is awake and aware.

Altered state of consciousness (ASC)

A state of consciousness that is distinctly different from normal waking consciousness in terms of quality of experience and levels of awareness.

Naturally occurring altered state of consciousness

A type of altered state of consciousness that occurs without intervention, such as sleep or daydreaming.

Induced altered state of consciousness

A type of altered state of consciousness that occurs due to a purposeful action or aid, such as meditation, hypnosis, or the influence of alcohol and/or drugs.

Consciousness continuum

A visual representation of the different states of consciousness that progress from lower levels of awareness to higher levels of awareness.

Sleep

A regular and naturally occurring altered state of consciousness that involves a loss of awareness and disengagement with internal and external stimuli.

REM (rapid eye movement) sleep

A type of sleep characterised by rapid eye movement, high levels of brain activity, and low levels of physical activity.

NREM (non-rapid eye movement) sleep

A type of sleep characterised by a lack of rapid eye movement and is subdivided into three different stages.

Sleep episode

The full duration of time spent asleep, from falling asleep until waking up.

Sleep cycle

An approximately 90-minute-period that repeats during a sleep episode in which an individual progresses through stages of REM and NREM sleep.

Hypnogram

A sleep graph that tracks the proportion of time spent in each stage of sleep, including awakenings, throughout a sleep episode.

Hypnagogic state

A state experienced when transitioning from being awake into stage 1 NREM sleep, in which some people experience feelings of floating or falling, or a hypnic jerk.

Electroencephalograph (EEG)

A device that detects, amplifies, and records the electrical activity of the brain.

Electromyograph (EMG)

A device that detects, amplifies, and records the electrical activity of the body's muscles.

Electro-oculograph (EOG)

A device that detects, amplifies, and records the electrical activity of the muscles responsible for eye movement.

Sleep diaries

A record of self-reported sleep periods, including estimated sleep time and judgements of sleep quality and nature.

Video monitoring

The use of camera and audio technologies to record an individual as they sleep, tracking sleeping and waking periods, movements, and sounds.

Biological rhythms

Repeated biological processes that are regulated by internal mechanisms.

Circadian rhythms

Biological and behavioural changes that occur as part of a cycle that lasts around 24 hours.

Sleep-wake cycle

A 24-hour-cycle that is made up of time spent sleeping and time spent awake and alert.

Ultradian rhythms

Biological and behavioural changes that occur in a cycle that lasts less than 24 hours.

Suprachiasmatic nucleus (SCN)

An area of the hypothalamus that is responsible for regulating an individual's sleep-wake patterns.

Pineal gland

A gland in the brain responsible for the production and release of melatonin.

Melatonin

A hormone released by the pineal gland typically at night-time to induce sleep as part of the sleep-wake cycle.

Cortisol

A hormone released by the adrenal cortex that is responsible for increasing alertness and maintaining heightened arousal.