AP Psych: 1.5-1.6

Consciousness

our subjective awareness of ourselves and our environment (to what extent we perceive our environment).

Cognitive Neuroscience

the interdisciplinary study of the brain activity linked with cognition.

Dual Processing

the principle that information is often simultaneously processed on separate conscious and unconscious tracks.

Parallel Processing

processing multiple aspects of a stimulus or problem simultaneously.

Sequential Processing

processing one aspect of a stimulus or problem at a time; generally used to process new information or to solve difficult problems.

Sleep

a periodic, natural loss of consciousness — as distinct from unconsciousness resulting from a coma, general anesthesia, or hibernation.

Circadian Rhythm

our biological clock; regular bodily rhythms (for example, of temperature and wakefulness) that occur on a 24-hour cycle.

Jet Lag

A temporary sleep disorder caused by a desynchronization between your internal circadian rhythm and the local external time.

Beta Waves

fast, low-amplitude brain waves of a normal consciousness, active thinking, and focused concentration.

Alpha Waves

the relatively slow brain waves of a relaxed, awake state.

NREM

non-rapid eye movement sleep; encompasses all sleep stages except for REM sleep.

NREM-1

hypnagogic sensations (fading alpha Waves and low frequency theta waves).

NREM-2

sleep spindles form, which are bursts of rapid, rhythmic brain wave activity that aid memory processing.

NREM-3

Deepest and most restorative phase of NREM sleep, often causing sleep inertia (groggy feeling when waking up); in Delta waves

Hallucinations

false sensory experiences, such as seeing something in the absence of an external visual stimulus.

Hypnagogic Sensations

bizarre experiences, such as jerking or a feeling of falling or floating weightlessly, while transitioning to sleep. (Also called hypnic sensations.)

Delta Waves

the large, slow brain waves associated with deep sleep.

REM

rapid eye movement sleep; a recurring sleep stage during which vivid dreams commonly occur. Also known as paradoxical sleep, because the muscles are relaxed (except for minor twitches) but other body systems are active. (Sometimes called R sleep.)

REM Rebound

The tendency for REM sleep to increase following REM sleep deprivation (created by repeated awakenings during REM).

Suprachiasmatic Nucleus (SCN)

a pair of cell clusters in the hypothalamus that controls circadian rhythm. In response to light, the SCN adjusts melatonin production, thus modifying our feelings of sleepiness.

Dream

a sequence of images, emotions, and thoughts passing through a sleeping person’s mind.

Activation Synthesis Theory

The neural theory that dreams are the brain's attempt to synthesize and make sense of random neural activity originating in the brainstem.

Consolidation Theory

The cognitive theory that dreams help us sift, sort, and fix the day's experiences into long-term memory storage.

Sleep Depreviation's Effect on Hormones

Ghrelin (hunger) increases, Leptin (hunger suppressant) decreases, Cortisol (stimulant to make fat) increases, Melatonin is disrupted.

Insomnia

recurring problems in falling or staying asleep.

Narcolepsy

a sleep disorder characterized by uncontrollable sleep attacks. The affected person may lapse directly into REM sleep, often at inopportune times.

REM Sleep Behavior Disorder

a sleep disorder in which normal REM paralysis does not occur; instead, twitching, talking, or even kicking or punching may occur, often acting out one’s dream.

Sleep Apnea

a sleep disorder characterized by temporary cessations of breathing during sleep and repeated momentary awakenings.

Somnambulism

Commonly known as sleepwalking; a disorder that occurs during deep NREM-3 sleep where an individual walks or performs behaviors while asleep.

Sensation

The process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment.

Perception

The process by which our brain organizes and interprets sensory information, enabling us to recognize objects and events as meaningful.

Psychophysics

The study of relationships between the physical characteristics of stimuli (like intensity) and our psychological experience of them.

Sensory Receptors

Specialized cells unique to each sense organ that detect specific physical stimuli and fire action potentials.

Bottom-up Processing

information processing that begins with the sensory receptors and works up to the brain’s integration of sensory information.

Top-down Processing

information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations.

Transduction

The fundamental process of converting one form of energy into another. 1. Receive sensory stimulation. 2. Transform that into neural impulses. 3. Deliever the neural information to the brain.

Signal Detection Theory

Predicts how and when we detect a faint stimulus (signal) amid background stimulation (noise); assumes there is no single absolute threshold and that detection depends on motivation, experience, and alertness.

Absolute Threshold

The minimum stimulation needed to detect a particular stimulus (light, sound, pressure) 50 percent of the time.

Difference Threshold (Just-Noticeable Difference / JND)

The minimum difference between two stimuli required for detection 50 percent of the time.

Weber’s Law

The principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage (a constant ratio), rather than a constant physical amount.

Sensory Adaptation

Diminished sensitivity to an unchanging, constant stimulus due to constant stimulation (e.g., stopping noticing the smell of a room).

Sensory Interaction

The principle that one sense may influence another, as when the smell of food influences its taste (giving rise to flavor).

Synesthesia

A rare neurological condition where stimulation of one sensory pathway leads to involuntary experiences in a second sensory pathway (e.g., "hearing" colors or "tasting" words).

Embodied Cognition

The influence of bodily sensations, gestures, and states on cognitive preferences and judgments (e.g., holding a warm drink makes you perceive someone as warmer).

Subliminal

Below one’s absolute threshold for conscious awareness (detected less than 50 percent of the time).

Priming

The activation, often unconsciously, of certain associations, predisposing one's perception, memory, or response to a later stimulus.

Wavelengths (Light)

The distance from the peak of one light wave to the peak of the next; determines the hue (color) we perceive.

Hue

The dimension of color that is determined by the wavelength of light; high frequency is closer to violet and lower is closer to red.

Intensity (Light)

The amount of energy in a light wave, determined by the wave's amplitude (height); influences our perception of brightness.

Cornea

The clear, protective outer layer covering the front of the eye; bends light to help focus it.

Pupil

The adjustable, opening in the center of the eye through which light enters.

Iris

A ring of muscle tissue that forms the colored portion of the eye around the pupil; controls the size of the pupil opening based on light levels.

Lens

The transparent structure behind the pupil that changes shape to help focus images on the retina.

Accommodation

The process by which the eye's lens changes shape (flattens or curves) to focus near or far objects on the retina.

Nearsightedness (Myopia)

A condition where nearby objects are seen clearly but distant objects are blurry because light rays focus in front of the retina.

Farsightedness (Hyperopia)

A condition where faraway objects are seen clearly but near objects are blurry because light rays focus behind the retina.

Retina

The light-sensitive inner surface of the eye, containing the photoreceptor rods and cones plus layers of neurons that begin the processing of visual information.

Fovea

The central focal point in the retina, around which the eye's cones cluster; area of sharpest, clearest vision (highest visual acuity).

Photoreceptors

Specialized neurons in the retina (rods and cones) that convert light energy into neural activity.

Rods

Photoreceptors concentrated in the periphery of the retina; detect black, white, and gray; necessary for peripheral and twilight (night) vision.

Cones

Photoreceptors concentrated near the fovea; function in daylight or well-lit conditions; detect fine detail and give rise to color sensations.

Ganglion Cells

Neurons in the retina whose axons twine together to form the optic nerve.

Optic Nerve (Visual Nerve)

The nerve that carries neural impulses from the eye to the brain (specifically to the thalamus, then visual cortex).

Blind Spot

The point at which the optic nerve leaves the eye, creating a "blind" spot because no photoreceptors (rods or cones) are located there.

Young-Helmholtz Trichromatic Theory

The theory that the retina contains three different types of color receptors (cones)—one most sensitive to red, one to green, and one to blue—which, when stimulated in combination, can produce the perception of any color.

Opponent-Process Theory

The theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision; explains why we cannot see a "reddish-green".

Afterimages

An optical illusion where a visual image persists after the stimulus is removed; directly demonstrates opponent-process theory (e.g., staring at green leaves a red afterimage).

Feature Detectors

Specialized nerve cells in the brain's visual cortex that respond to specific features of the stimulus, such as shape, angle, or movement.

Parallel Processing (Vision)

The brain's ability to process multiple visual dimensions (color, motion, shape, depth) simultaneously rather than sub-processing them one by one.

Dichromatism

A form of color blindness where an individual lacks one of the three types of cones, making them unable to distinguish between certain colors (usually red and green).

Monochromatism

Rare, total color blindness where the individual lacks all or all-but-one cone types; vision is purely in shades of gray.

Prosopagnosia

A neurological condition characterized by the inability to recognize faces; often called "face blindness," while object recognition remains intact.

Blindsight

A condition in which a person can respond to a visual stimulus without consciously experiencing it; occurs due to localized damage to the conscious visual cortex while leaving unconscious visual pathways intact.

Wavelengths / Frequency (Sound)

The number of complete wavelengths that pass a point in a given time; determines the pitch of a sound.

Pitch

A tone's experienced highness or lowness; depends entirely on frequency.

Amplitude (Sound)

The height of a sound wave; determines the loudness or intensity of the sound (measured in decibels).

Middle Ear

The chamber between the eardrum and cochlea containing three tiny bones (hammer, anvil, and stirrup / ossicles) that concentrate the vibrations of the eardrum on the cochlea's oval window.

Cochlea

A snail-shaped, bony, fluid-filled tube in the inner ear; sound waves traveling through the cochlear fluid trigger nerve impulses via hair cells.

Inner Ear

The innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs.

Place Theory

In hearing, the theory that links the pitch we hear with the specific place where the cochlea's membrane is stimulated; best explains how we hear high pitches.

Frequency Theory

In hearing, the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch; best explains how we hear low pitches.

Volley Theory (Volley Principle)

An extension of frequency theory stating that neural cells can alternate firing in rapid succession to achieve a combined frequency, explaining how we perceive mid-range pitches.

Conduction Deafness

Hearing loss caused by damage to the mechanical system (eardrum or ossicles) that conducts sound waves to the cochlea.

Sensorineural Deafness

Hearing loss caused by damage to the cochlea's receptor cells (hair cells) or to the auditory nerves; also called nerve deafness.

Cochlear Implant

A device for converting sounds into electrical signals and stimulating the auditory nerve directly through electrodes threaded into the cochlea.

Sound Localization

The process by which the brain determines the location of a sound source based on discrepancies in the timing and intensity of the sound arriving at each ear.

Olfactory System (Olfaction)

The sensory system used for olfaction (smell); unique because its sensory signals bypass the thalamus and go directly to the olfactory bulb and limbic system.

Thalamus

The brain's sensory control center; it routes signals for all senses (except smell) to higher cortical areas.

Pheromones

Chemical signals released by an animal that communicate information and affect the behavior or physiology of other animals of the same species.

Gustation

The chemical sense of taste.

Taste Receptors

Sensory receptors located inside taste buds on the papillae of the tongue that respond to chemical molecules in food.

Umami

One of the five basic tastes; a savory, brothy, or meaty taste triggered by glutamate.

Oleogustus

A proposed sixth basic taste; the distinct, unique taste of fat.

Supertasters

Individuals with a high density of taste buds/papillae, making them exceptionally sensitive to bitter tastes and spicy foods.

Medium Tasters

Individuals with an average density of taste buds; represent the majority of the population.

Nontasters

Individuals with a low density of taste buds who are relatively insensitive to bitter or subtle tastes.

Four Basic Touch Sensations

Pressure, warmth, cold, pain.

Pain

A biopsychosocial phenomenon, perceived through biological, psychological, and social-cultural pathways.

Gate-Control Theory

The theory that the spinal cord contains a neurological "gate" that either blocks pain signals or allows them to pass onward to the brain; the gate is opened by the activity of pain signals traveling up small nerve fibers and is closed by activity in larger fibers or by information coming from the brain.