Consciousness, Sleep, Drugs, and Memory Key Concepts

Conscious

Immediate awareness.

Preconscious

Accessible memories.

Unconscious

Drives and repressed trauma.

Circadian rhythm

A 24-hour biological clock regulating sleep and wake cycles.

Evolutionary/circadian models of sleep

Species evolved sleep patterns to increase survival; predators sleep more, prey less.

Percentage of life spent asleep

About one-third.

Percentage of Americans losing sleep due to stress

65%.

PER3 gene

Associated with being a morning or night person.

Freud's wish fulfillment theory of dreams

Dreams express unconscious desires symbolically.

Activation-synthesis theory

Dreams are byproducts of random neural activity formed into a story.

Carl Jung's view on dreams

Self-portraits of the psyche for integration and wholeness.

REM sleep

Rapid eye movement, vivid dreams, beta waves, motor cortex blocked by GABA.

Less active brain area during REM

Prefrontal cortex.

Psychoactive drugs

They mimic neurotransmitters and hijack reward pathways.

Factors influencing drug effects

Dose, Set (mindset), and Setting (environment).

Long-term effects of drug use

Dopamine depletion, depression, poor memory, addiction, and brain damage.

Depressants

Decrease nervous system activity.

Alcohol's effect on neurotransmitters

Increases GABA, decreases glutamate.

Examples of depressants

Alcohol, sedatives, opioids, anti-anxiety meds.

Stimulants

Increase neural firing and arouse the nervous system.

Examples of stimulants

Amphetamines, cocaine, nicotine, caffeine, MDMA.

Hallucinogens

Distort or intensify sensory experiences.

Examples of hallucinogens

LSD, DMT, peyote, psilocybin, marijuana.

Marijuana as a hallucinogen

THC can cause mild hallucinations and time distortion.

Marijuana as a stimulant

Can increase alertness and sociability.

Marijuana as a depressant

Causes relaxation and reduced inhibitions.

Types of memory

Short-term (working) and long-term memory.

Explicit and implicit memory

Explicit: conscious; Implicit: unconscious.

Semantic and episodic memories

Semantic: facts; Episodic: personal experiences.

Procedural memories

Skills and habits stored unconsciously.

Stages of memory

Encoding, Storage, and Retrieval.

Increasing short-term memory capacity

Chunking information.

Magical number for short-term memory

7 ± 2 items.

Serial position effect

Primacy: first items; Recency: last items remembered.

State-dependent memory

Recall is easier in the same physical or emotional state.

Decay theory

Memory traces fade over time with disuse.

Interference theory

Old/new information disrupts recall.

Motivated forgetting

Repression of painful memories.

Brain area for short-term memory

Dorsolateral prefrontal cortex.

Brain area for long-term memory

Hippocampus and cerebral cortex.

HM

Patient unable to form new long-term memories after hippocampus removal.