Unit 4 Ap psych vocab

AP Psychology Chapter 4 Vocabulary for Myers 4E textbook

Sensation

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

Absolute Threshold

the minimum stimulus energy needed to detect a particular stimulus 50 percent of the time.

Just-Noticeable difference (Difference Threshold)

the minimum difference between two stimuli required for detection 50 percent of the time. We experience the difference threshold as a just noticeable difference

Weber’s Law

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

Sensory Adaptation

diminished sensitivity as a consequence of constant stimulation.

Sensory interaction

the principle that one sense may influence another, as when the smell of food influences its taste.

Synesthesia

Where the stimulation of one sense (such as hearing sound) triggers an experience of another (such as seeing color)

Retina

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

Blind Spot

the point at which the optic nerve leaves the eye, creating a “blind” spot because no receptor cells are located there.

Visual Nerve (optic nerve)

the nerve that carries neural impulses from the eye to the brain.

Lens

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

Accommodation

in sensation and perception, the process by which the eye’s lens changes shape to focus near or far objects on the retina.

Nearsightedness

If the lens focuses the image on a point in front of the retina, you see near objects clearly, but not distant objects.

Farsightedness

Visual condition where distant objects are seen more clearly than nearby objects because the image is focused behind the retina.

Fovea

the central focal point in the retina, around which the eye’s cones cluster.

Photoreceptors

Specialized cells in the retina that convert light into neural signals, enabling vision. Two main types: rods (sensitive to low light), cones (responsible for color vision).

Transduction

conversion of one form of energy into another. In sensation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brain can interpret.

rods

retinal receptors that detect black, white, and gray, and are sensitive to movement; necessary for peripheral and twilight vision, when cones don’t respond.

cones

retinal receptors that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. Cones detect fine detail and give rise to color sensations.

Young-Helmholtz trichromatic (three-color) theory

the theory that the retina contains three different types of color receptors—one most sensitive to red, one to green, 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, blue-yellow, white-black) enable color vision. For example, some cells are stimulated by green and inhibited by red; others are stimulated by red and inhibited by green.

Afterimages

Visual sensations that continue after the original stimulus is removed, typically resulting from the over stimulation of photoreceptors in the eye.

Ganglion cells

Neurons in the retina that receive visual information from photoreceptors via bipolar cells and transmit it through their axons to the brain, forming the optic nerve.

Dichromatism

color blindness or one of the three basic color channels in the eye (red green or blue) is absent or not functioning properly leading to difficulty in distinguishing certain colors

Monochromatism

a rare form of color blindness where only one type of photoreceptors is functional leading to the perception of the world in shades of grey without color differentiation

Prosopagnosia

also known as face blindness this neurological disorder is characterized as the inability to recognize faces including familiar ones due to damage or dysfunction in the brain areas responsible for facial recognition typically in fusiform gyrus

Blindsight

a condition in which a person can respond to a visual stimulus without consciously experiencing it.

Wavelengths

the distance from the peak of one light or sound wave to the peak of the next. Electromagnetic wavelengths vary from the short blips of gamma rays to the long pulses of radio transmission.

Amplitude

the height of a wave (sound or light) which determines the intensity or strength of the wave and hearing the height of sound waves determine the perceived loudness

Place Theory

in hearing, the theory that links the pitch we hear with the place where the cochlea’s membrane is stimulated.

Volley Theory

auditory nerve fibers respond to a sound by firing action potentials slightly out of sync with one another together they produce a combined frequency that matches the frequency of the sound wave, enabling the perception of pitch

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. (Also called temporal theory.)

Conduction deafness

a less common form of hearing loss, caused by damage to the mechanical system that conducts sound waves to the cochlea.

Sensorineural deafness

hearing loss caused by damage to the cochlea’s receptor cells or to the auditory nerves; the most common form of hearing loss, also called nerve deafness.

Sound Localization

the process by which the brain determines the localization of a sound source. analyzes differences in time it takes for a sound to reach each ear and the difference in sound intensity between ears

Olfactory System

sensory system responsible for the sense of smell (olfaction)

Thalamus

the brain’s sensory control center, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla.

Pheromones

signals secreted by other members of their species some serve as sexual attractants

Gustation

sense of taste

Taste receptors

also known as taste buds specialized sensory organs located primarily on the tongue, but also roof of mouth and throat, detects 5 basic tastes: sweet sour salty bitter umami

Umami

savory meaty taste best experienced as flavor enhancer monosodium glutamate

Oleogustus

taste sensation that detects the flavor of fats/fatty acids

Supertasters

adults who have heightened sense of taste due to a higher number of taste buds compared to the average person

Medium Tasters

individuals who sense of taste falls between super tasters and non tasters moderate sensitivity to flavors

Nontasters

individuals with low sensitivity to taste particularly bitterness. fewer taste buds

Perception

the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events.

Bottom-up Processing

analysis 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.

schemas

a concept or framework that organizes and interprets information

Perceptual set

a mental predisposition to perceive one thing and not another.

Attention

a state in which cognitive resources are focused on certain aspects of the environment rather than on others and the CNS is in a state of readiness to respond to stimuli

Selective attention

the focusing of conscious awareness on a particular stimulus.

Cocktail Party Effect

the ability to attend to one of several speech streams while ignoring others, as when one is at a cocktail party.

Inattentional Blindness

failing to see visible objects when our attention is directed elsewhere.

Change Blindness

failing to notice changes in the environment; a form of inattentional blindness.

Gestalt Psychology

an organized whole. Gestalt psychologists emphasized our tendency to integrate pieces of information into meaningful wholes.

Closure

we fill in gaps to create a complete whole object a gestalt principle of organization

Figure and Ground

the organization of the visual field into objects (the figures) that stand out from their surroundings (the ground).

Proximity

we group nearby figures together

Similarity

One of the gestalt principles of organization people tend to organize objects with similar qualities into perceptual groups and interpret them as a whole

Binocular cues

a depth cue, such as retinal disparity, that depends on the use of two eyes.

Retinal disparity

a binocular cue for perceiving depth. By comparing retinal images from the two eyes, the brain computes distance—the greater the disparity (difference) between the two images, the closer the object.

monocular cues

a depth cue, such as interposition or linear perspective, available to either eye alone.

Relative Clarity

objects that appear sharp clear and detailed are seen as closer than more hazy objects

Relative size

the depth cue in which we perceive distance based on the comparison of sizes between objects

Texture gradient

the progressive decline in resolution of textures as the viewer moves away from them

Linear Perspective

a monocular depth cue parallel lines appear to meet in the distance. the greater the angle of convergence the greater the perceived distance

Interposition

if object partially blocks our view of another we perceive it as closer

Perceptual constancies

perceiving objects as unchanging (having consistent color, brightness, shape, and size) even as illumination and retinal images change

Apparent Motion

a illusion of motion or change in size of a visual stimulus.