Consciousness

Consciousness and Altered States

• Consciousness is the personal experience of the world, body, thoughts, moment by moment
• Controlled processing requires effort and attention (e.g., writing an essay)
• Automatic processing requires little or no effort (e.g., brushing teeth)
• Divided attention is the ability to do multiple tasks simultaneously (e.g. listening to music while studying)
• Humans need 7-10 hours of sleep, but this varies based on age, health, genetics, etc.
• Circadian rhythm refers to repeated bodily changes every 24 hours, regulated by the suprachiasmatic nucleus (SCN).
• SCN is in the hypothalamus, considered the biological clock.
• Pineal gland secretes melatonin, crucial for the sleep-wake cycle.
• Awake and alert involves beta waves (greater than 13 Hz).
• Calm wakefulness involves alpha waves (8-12 Hz).
• Stage 1 sleep features theta waves (4-7 Hz) and possible myoclonic jerks, hypnagogic imagery.
• Stage 2 sleep includes sleep spindles and k-complexes.
• Stage 3 and 4 sleep contain delta waves (1-2 Hz); the difference is that stage 4 has greater than 50% delta waves. Deep sleep occurs in stage 3 and 4.
• REM (rapid eye movement) sleep is marked by brain activity, vivid dreaming, and occurs about 20% of the time. If REM sleep is not enough the body will spend more time in REM in the following sleep cycle.
• Sleep helps with energy conservation, survival, and bodily restoration.
• Insomnia is a sleep disorder causing difficulty falling or staying asleep, influenced by factors including age, medications, exercise, mental state, and bedtime routines.

Behavioral and Pharmacological Treatments for Insomnia

• Behavioral therapies for insomnia include a regular wake-up schedule, bed use only for sleep, exercise, and avoiding caffeine and alcohol in the evenings.

• Pharmacological treatments can lead to rebound insomnia after cessation of use.

• Narcolepsy is a sleep disorder with unpredictable sleep-wake cycles. and is partially caused by insufficient hypocretin-producing neurons in the hypothalamus.

• Symptoms can include sleep attacks, cataplexy, hypnagogic/hypnopompic hallucinations, and sleep paralysis.

• Sleep apnea is a disorder of airway blockage during sleep, causing daytime drowsiness, and carries potential health risks.

Sleep Disorders

• Treatments for sleep apnea may include weight loss and CPAP (continuous positive airway pressure) therapy.
• Night terrors are sleep disturbances typically occurring in children during stages 3 or 4 sleep, characterized by screaming, confusion, and sweating.
• Sleepwalking (somnambulism) is a sleep disorder where a person walks while asleep; is harmless (generally).
• Sleep apnea sufferers may experience daytime sleepiness, weight gain, hearing loss, irregular heartbeats, and increased mortality risk.

Dream Interpretation

• Freud's dream protection theory associates dreams with wish fulfillment and prevents unconscious thoughts from affecting sleep.
• Manifest content describes dream events, while latent content represents their underlying meaning.
• Activation-synthesis theory proposes that dreams occur due to random brain activity.
• Dreams contain reflections of waking thoughts.

Altered States of Consciousness

• Deja vu presents a feeling of familiarity despite perceived novelty. It can be caused by temporal lobe seizures or excessive dopamine.
• Hypnosis involves suggestion techniques to create altered states of consciousness, with effects varying based on suggestibility.
• Psychoactive drugs alter brain processes through chemicals similar to those found in the brain.
• Blood-brain barrier regulates substance permeability in the brain.
• Substance Use Disorder (SUD) is diagnosed when a drug results in significant repeated health problems.
• Drug tolerance is a condition requiring higher doses to produce the same effect.
• Withdrawal is the unpleasant experience when a user stops drug consumption.
• Depressants include alcohol, barbituates, and tranquilizers, decreasing nervous system activity.
• Stimulants include amphetamines, and cocaine, increasing nervous system activity.
• Opiates are derived from the opium poppy, and bind to endorphin receptors, producing pain relief and euphoria (morphine, codeine, heroin).
• Hallucinogens/psychedelics alter perception, including cannabis (THC).