Consciousness, Sleep, Dreams, Substance Use, Sensation, and Perception Lecture Notes

Vocabulary flashcards covering topics from consciousness, sleep, and dreams to substance use, sensation, and perception.

Consciousness

Our awareness of ourselves and our environment, including thoughts, feelings, perceptions, and external surroundings.

Circadian Rhythm

A roughly 24-hour biological cycle that regulates sleep, wakefulness, body temperature, and hormone release.

NREM (Non-Rapid Eye Movement) Sleep

One of the two main types of sleep, divided into three stages (N1, N2, N3), characterized by deeper relaxation progressively.

REM (Rapid Eye Movement) Sleep

One of the two main types of sleep, characterized by highly active brain waves similar to waking, rapid eye movements, vivid dreams, and muscle paralysis.

NREM Stage 1 (N1)

Light sleep, a transition from wakefulness, characterized by Theta waves and potential hypnic jerks.

NREM Stage 2 (N2)

Deeper relaxation than N1 but still light sleep, characterized by sleep spindles and K-complexes, with dropping heart rate and body temperature.

NREM Stage 3 (N3/slow-wave sleep)

The deepest sleep stage, characterized by Delta waves, where restorative processes occur and growth hormone is released.

Sleep Cycle

A typical sleep duration of about 90 minutes per cycle, with adults usually going through 4-6 cycles per night.

Restoration Theory of Sleep Function

The theory that sleep repairs the body and brain, restores energy, and consolidates memory.

Evolutionary (Adaptive) Theory of Sleep Function

The theory that sleep evolved for survival, conserving energy and keeping us safe at night.

Memory/Information Processing Theory of Sleep Function

The theory that sleep (especially REM) helps process and consolidate learning and experiences.

Insomnia

A sleep disorder characterized by difficulty falling or staying asleep.

Sleep Apnea

A sleep disorder where breathing repeatedly stops during sleep.

Narcolepsy

A sleep disorder characterized by sudden, uncontrollable sleep attacks.

Night Terrors

An intense fear and screaming episode during NREM deep sleep, where the person is not fully awake.

Sleepwalking

Moving or performing actions while in deep NREM sleep.

REM Sleep Behavior Disorder

A sleep disorder where individuals act out their dreams due to a lack of REM paralysis.

Dreams

Mental experiences during sleep, often vivid and story-like.

REM Dreams

Dreams that are more vivid, emotional, and bizarre, occurring during REM sleep.

NREM Dreams

Dreams that are more realistic, thought-like, and less emotional, occurring during NREM sleep.

Freud's Wish-Fulfillment Theory of Dreams

The theory that dreams represent unconscious desires and conflicts.

Information Processing Theory of Dreams

The theory that dreams help consolidate memory and learning.

Physiological Function Theory of Dreams

The theory that dreams stimulate brain pathways to keep them active.

Activation-Synthesis Model of Dreams

The theory that dreams are the brain's attempt to make sense of random neural activity.

Cognitive Development Theory of Dreams

The theory that dreams reflect brain maturation and problem-solving.

Substance Use Disorder

A maladaptive pattern of substance use leading to significant impairment or distress (e.g., inability to cut down, cravings).

Psychoactive Drugs

Chemicals that alter perceptions, mood, consciousness, or behavior by affecting the brain.

Tolerance

Needing larger doses over time to get the same effect from a substance.

Addiction

Compulsive craving and use of a substance despite negative consequences.

Withdrawal

Distressing physical and psychological symptoms (e.g., anxiety, shaking, sweating, nausea) experienced when reducing or stopping drug use.

Titration Method

A method of gradually reducing drug dosage over time to minimize withdrawal symptoms and safely wean a person off a substance.

Depressants

Drugs that slow CNS activity, such as alcohol, barbiturates, and benzodiazepines, causing relaxation and reduced anxiety.

Stimulants

Drugs that increase CNS activity, such as caffeine, nicotine, cocaine, and amphetamines, causing alertness, energy, and euphoria.

Hallucinogens (Psychedelics)

Drugs that alter perception and consciousness, such as LSD, psilocybin, and marijuana (THC has both stimulant and hallucinogen effects).

Opiates (Narcotics)

Drugs that provide pain relief and euphoria, such as morphine, heroin, codeine, and fentanyl, with a high risk of addiction and overdose.

Sensation

The process of detecting raw sensory input from the environment (e.g., light hitting your retina, sound waves vibrating your eardrum).

Perception

The brain's interpretation of sensory input into meaningful experiences (e.g., recognizing light as your friend's face, hearing sound as music).

Transduction

The process of converting physical energy from the environment into neural signals (e.g., photoreceptors converting light waves into electrical signals).

Bottom-up Processing

Processing that starts with raw sensory input, building upward to perception (e.g., piecing together what an unfamiliar fruit is).

Top-down Processing

Processing guided by prior knowledge, expectations, and context (e.g., recognizing messy handwriting because you know the sentence).

Psychophysics

The study of the relationship between physical stimuli and our psychological experiences of them.

Fechner's Contribution

Introduced methods to measure thresholds, laying groundwork for experimental psychology.

Signal Detection Theory

Explains how we detect stimuli under uncertainty, considering both sensitivity and decision-making factors.

Absolute Threshold

The minimum stimulus intensity needed to detect it 50% of the time.

Difference Threshold (Just Noticeable Difference, JND)

The smallest detectable difference between two stimuli.

Sensory Adaptation

Diminished sensitivity after prolonged exposure to a stimulus.

Wavelength (Light Waves)

The distance between wave peaks, perceived as color/hue.

Amplitude (Light Waves)

The height of a wave, perceived as brightness.

Cornea

The clear outer layer of the eye that bends light.

Pupil

The opening in the eye that controls light entry.

Iris

The colored muscle of the eye that adjusts pupil size.

Lens

Focuses light onto the retina, changing shape through accommodation.

Retina

The layer at the back of the eye containing photoreceptors (rods and cones).

Fovea

The center of the retina, with a high concentration of cones for sharp vision.

Optic Nerve

Transmits visual signals from the retina to the brain.

Blind Spot

The area in the retina with no photoreceptors where the optic nerve exits.

Rods

Photoreceptors that are more numerous, concentrated in the periphery, detect light/dark (low-light vision), and have low acuity with no color detection.

Cones

Photoreceptors that are concentrated in the fovea, responsible for color vision, high acuity (fine detail), and work best in bright light.

Trichromatic Theory (Young-Helmholtz)

Theory that cones are sensitive to three colors (red, green, blue) which combine to form all colors.

Opponent-Process Theory

Theory that opposing pairs of colors (red-green, blue-yellow, black-white) process visual information, where one active suppresses the other, explaining afterimages.

Figure-Ground

A Gestalt principle of distinguishing the main object (figure) from the background (ground).

Grouping Principles (Gestalt)

Principles including proximity (things close together are grouped), similarity (similar items are grouped), continuity (perceiving smooth, continuous patterns), and closure (filling in gaps to create whole objects).

Retinal Disparity

A binocular depth cue where each eye sees slightly different images, and the brain merges them for depth perception.

Convergence

A binocular depth cue where eyes turn inward more for close objects.

Monocular Cues

Depth cues that require only one eye, such as relative size, interposition, linear perspective, relative motion (motion parallax), texture gradient, and light/shadow.

Perceptual Constancy

The ability to perceive objects as unchanging despite changes in sensory input (e.g., color constancy, shape constancy, size constancy).

Frequency (Sound Waves)

The number of cycles per second, perceived as pitch.

Amplitude (Sound Waves)

The height of a wave, perceived as loudness.

Range of Human Hearing

From 20 Hz to 20,000 Hz, with infrasound below and ultrasound above this range.

Outer Ear

Comprises the pinna (collects sound) and the auditory canal.

Middle Ear

Contains the eardrum (vibrates) and ossicles (hammer, anvil, stirrup) that amplify sound.

Inner Ear

Contains the cochlea (fluid-filled, with basilar membrane and hair cells that transduce sound) and semicircular canals (for balance).

Auditory Nerve

Sends sound signals from the cochlea to the brain.

Cortical Magnification

More brain area in the sensory cortex devoted to body parts or regions with high sensitivity (e.g., hands, lips), as shown in a homunculus map.

Biopsychosocial Model of Pain

Explains pain perception through biological (nerves, spinal cord), psychological (attention, mood, expectation), and social/cultural (norms, support systems) factors.

Chemical Senses

Taste and smell, which respond to molecules in food/air that bind to receptors.

Five Basic Tastes

Sweet, sour, salty, bitter, and umami.

Supertaster

A person with more taste buds, resulting in very high sensitivity to flavors, especially bitter.

Taste Aversion

A learned avoidance of a food after one bad experience, often from nausea.

Olfactory Receptors (Smell Receptors)

Located in the olfactory epithelium, they connect directly to the olfactory bulb (not routed through the thalamus like other senses).