Consciousness and Its Mysteries

Consciousness

• Consciousness: a person's subjective experience of the world and their mind.
• Phenomenology: how things seem to a conscious person.

Mysteries of Consciousness

• The Problem of Other Minds: the fundamental difficulty in perceiving the consciousness of others.
• People judge minds based on capacity for experience and capacity for thought.
• The Mind-body Problem: how the mind is related to the brain and body.
• Descartes's view: mental events are tied to the pineal gland.
• Contemporary view: mental events are intimately connected to brain events.

Four Basic Principles of Consciousness

• Intentionality: being directed towards an object.
• Unity: resistance to division.
• Selectivity: the capacity to include some objects but not others.
• Transience: the tendency to change.

Levels of Consciousness

• Consciousness ranges from minimal, to full and self-consciousness.

Suppressing Thoughts

• Mental control: attempting to change conscious states of mind.
• Thought suppression: consciously avoiding a thought.
• Rebound effect of thought suppression: a thought is more likely to return to consciousness after being suppressed.

The Unconscious Mind

• Dynamic unconscious: an active system encompassing a lifetime of hidden memories, desires, and the inner struggle to control these.
• Freudian slips: found in speech.
• Repression: removes unacceptable thoughts and memories from consciousness, storing them in the unconscious.

A Modern View of the Cognitive Unconscious

• Cognitive unconscious: all mental processes that give rise to a person's thoughts, choices, and emotions.
• Dual process theories: the brain uses two different systems to process information: a fast, automatic, and unconscious system and a slow, effortful, and conscious system..
• Kahneman (2001): described Systems 1 and 2.

Sleep and Dreaming

• Altered state of consciousness: differs from the normal experience of the world and the mind.
• Accompanied by changes in thinking, disturbances in the sense of time, feelings of loss of control, or changes in emotional expression.
• Altered body image, sense of self, or perceptual distortions; changes in meaning or significance.

Sleep

• Adaptive theory of sleep: sleep is the evolutionary outcome of self-preservation.
• Restorative theory of sleep: sleep allows the brain and body to restore depleted chemical resources and eliminate waste.

Sleep Cycle

• Circadian rhythm: a naturally occurring 24-hour cycle.
• EEG changes in brain waves (beta, alpha, theta, and delta) are observed during the sleep cycle.
• 5 stages of sleep: Stages 1 through 4 and REM sleep.
• REM sleep: characterized by rapid eye movements and high brain activity; dreaming often occurs during this stage.
• The body is usually immobilized during REM sleep.

Sleep Needs and Deprivation

• Across a lifetime, approximately an hour of sleep is required for every two hours of waking time.
• Memories deteriorate without adequate sleep.
• REM sleep deprivation has the most detrimental effect.
• Slow-wave sleep (stages 3 and 4) deprivation also has a large impact.

Sleep Disorders

• Insomnia: difficulty falling or staying asleep.
• Sleep apnea: person stops breathing for brief periods while asleep.
• Somnambulism (sleepwalking): occurs when a person arises and walks around during sleep.
• Narcolepsy: disorder involving sudden sleep attacks during waking activity.
• Sleep paralysis: the experience of waking up unable to move.
• Night terrors (sleep terrors): abrupt awakenings with panic and intense emotional arousal.

Dreams

• Dream consciousness: distinguishes dreaming from waking consciousness.
• Major characteristics: intense emotion, illogical thinking, meaningful sensations, uncritical acceptance, and difficult remembering on waking.

Dream Theories

• Freud's view: dreams hold meaning.
• Manifest content: surface topic, or superficial meaning of dreams.
• Latent content: true/underlying meaning of dreams.
• Activation-synthesis model: the brain imposes meaning on random neural activity.

Drugs and Consciousness

• Levels of involvement: substance use, intoxication, abuse, dependence, tolerance, withdrawal, and addiction.
• Addiction is characterized by physical or psychological dependence.

Depressants

• Slow down or curb central nervous system activity.
• Reduce tension and anxiety, slow movement, and impair cognition; high doses can arrest vital functions and cause death.
• Alcohol is the "king" of depressants.
• Expectancy theory: alcohol's effects result from people's expectations of how alcohol will influence them.
• Balanced placebo design: studies designed to test the influence of expectancy on behaviour, in relation to a placebo.
• Alcohol myopia: attention is hampered by alcohol, leading a person to deal with complex situations in simple ways.
• Barbiturates: used in sleeping aids and surgical anesthetics; less popular than alcohol but still abused.
• Benzodiazepines: minor tranquilizers used to treat anxiety; includes Valium and Xanax.

Stimulants

• Stimulants excite the central nervous system, and increase arousal and activity levels.
• Includes caffeine, amphetamines, nicotine, cocaine, modafinil, and Ecstacy (MDMA, X, E).
• Stimulants elicit euphoria and feelings of confidence and motivation.

Narcotics

• Narcotics (opiates): highly addictive drugs derived from opium; relieve pain.
• Including heroin, morphine, methadone, and codeine.
• Drug properties closely related to endorphins.

Hallucinogens

• Hallucinogens: alter sensation and perception.
• Often cause visual and/or auditory hallucinations.
• Include LSD (acid), mescaline, psilocybin, PCP, and ketamine.
• Effects are dramatic and unpredictable.

Marijuana

• Marijuana: contains tetrahydrocannabinol (THC).
• Produces a mild hallucinogenic intoxication, impacting judgement, short-term memory, motor skills, and coordination.
• Medicinal uses are controversial.
• Considered a gateway drug, along with alcohol and tobacco.
• Harm reduction approach: aims to minimize harm resulting from high-risk behaviours.

Explore the complexities of consciousness in this quiz, which covers key concepts such as phenomenology, the problem of other minds, and the mind-body problem. Dive into the four principles of consciousness and understand the different levels, from minimal to self-consciousness. Test your knowledge on how thoughts can be suppressed and the implications of mental control.