Mysteries of Consciousness

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 difficulty in perceiving the consciousness of others.
• People judge minds according to their capacity for experience.
• The Mind-Body Problem: the relationship between the mind and the brain/body.
• Descartes: believed the pineal gland is the connection between mind and body.
• Contemporary view: mental events are intimately connected with brain events.

Four Basic Principles of Consciousness

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

Levels of Consciousness

• Consciousness ranges from minimal to full to self-consciousness.
• Minimal Consciousness: a low level of awareness.
• Full Consciousness: a high level of awareness.
• Self-Consciousness: awareness of oneself as an individual.

Suppressing Thoughts

• Mental control: attempting to change conscious states of mind.
• Thought suppression: avoiding a thought.
• Rebound effect: the thought returning to consciousness more frequently after suppression.

The Unconscious Mind

• Dynamic unconscious: an active system encompassing lifetime memories, instincts, desires, and inner struggles to control these forces.
• Freudian slips: errors in speech.
• Repression: a mental process that removes unacceptable thoughts and memories from consciousness.

A Modern View of the Cognitive Unconscious

• Cognitive unconscious: all mental processes that produce thoughts, choices, emotions, and behaviors—even though not experienced by the person.
• Dual process theories: two different systems in the brain for processing information.
• Fast, automatic, and unconscious processing.
• Slow, effortful, and conscious processing.
• Kahneman (2001): Systems 1 and 2.

Sleep and Dreaming

• Altered state of consciousness: a form of experience that differs from normal subjective experience.
• Associated with changes in thinking, disturbances in the sense of time, feelings of loss of control, changes in emotional expression, and alterations in body image or the sense of self, perceptual distortions, and changes in meaning or significance.

Sleep

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

Sleep Cycle

• Circadian rhythm: a naturally occurring 24-hour cycle.
• EEG changes in beta, alpha, theta, and delta waves.
• Five stages of sleep (1-4) and REM sleep.
• REM sleep: rapid eye movement sleep, characterized by high levels of brain activity, dreaming often occurs, body is generally immobilized.
• Electrooculography (EOG): instrument that measures eye movements.

Sleep Needs and Deprivation

• Across a lifetime, an average of 1 hour of sleep is needed for every 2 hours awake.
• Memories deteriorate without sleep.
• REM sleep deprivation has the most detrimental effects, followed by stages 3 and 4 slow-wave sleep deprivation.

Sleep Disorders

• Insomnia: difficulty falling asleep or staying asleep.
• Sleep apnea: brief pauses in breathing while asleep.
• Somnambulism (sleepwalking): arising and walking around while asleep.
• Narcolepsy: sudden sleep attacks during waking activities.
• Sleep paralysis: 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.
• Characteristics of dreams include intense emotion, illogical thought, meaningful sensation, uncritical acceptance, and difficulty remembering dreams on waking.

Dream Theories

• Freud's view: dreams hold meaning.
• Manifest content: dream's apparent topic or superficial meaning.
• Latent content: dream's true underlying meaning.
• Activation-synthesis model: the brain imposes meaning on random neural activity when producing dreams. fMRI scans show active brain areas involved in emotions and visual imagery, but not the prefrontal cortex.

Drugs and Consciousness

• Levels of involvement in substance use: use, intoxication, abuse, dependence, tolerance, withdrawal, addiction, physical vs. psychological dependence.

Depressants

• Slow down or curb the activity of the central nervous system, reducing feelings of tension and anxiety, slowing movement and impairing cognitive processes. High doses can arrest vital functions and cause death.
• Alcohol is the "king" of depressants.
• Expectancy theory: alcohol's effects are influenced by people's expectations.
• Balanced placebo design: used to study expectancy
• Alcohol myopia: alcohol hampers attention, people respond in simple ways to complex situations.

Types of Psychoactive Drugs

• Barbiturates: sleeping aids and surgical anesthetics (Seconal, Nembutal).
• Benzodiazepines: minor tranquilizers/anxiety drugs (Valium, Xanax).
• Toxic inhalants (glue, hair spray, etc) are easily accessible and can cause harm.

Stimulants

• Stimulants: excite the central nervous system, heighten arousal and activity levels.
• Types include caffeine, amphetamines, nicotine, cocaine, modafinil, and ecstasy.
• Stimulants elicit euphoria and confidence/motivation.

Narcotics

• Narcotics (opiates): highly addictive drugs derived from opium, relieving pain.
• Examples include heroin, morphine, methadone, and codeine.
• Similar to endorphins.

Hallucinogens

• Hallucinogens: drugs that alter sensation and perception, often cause visual and auditory hallucinations.
• Examples include LSD, mescaline, psilocybin, PCP, and ketamine.
• Effects can be dramatic and unpredictable.

Marijuana

• Marijuana: leaves and buds of hemp plant, containing tetrahydrocannabinol (THC)
• Mildly hallucinogenic, affects judgment, short-term memory, motor skills, and coordination.
• Medicinal uses are controversial.
• Considered a gateway drug, increasing the risk for more harmful drugs (tobacco, etc.).
• Harm reduction approach focuses on reducing harm from high-risk behaviors.