AP PSYCH Unit 3 - Sensation and Perception

Sensation

The process by which sensory receptors detect stimuli and transmit information to the brain

Perception

The process of organizing and interpreting sensory information

Bottom-up Processing

Analysis that begins with sensory receptors and works up to the brain

Top-down Processing

Information processing guided by expectations and prior knowledge

Selective Attention

The ability to focus on one stimulus while ignoring others

Divided Attention

The ability to attend to multiple tasks simultaneously

Inattentional Blindness

Failing to see visible objects when attention is directed elsewhere

Change Blindness

Failing to notice changes in the environment

Psychophysics

The study of relationships between physical stimuli and sensory experiences

Absolute Threshold

The minimum stimulation needed to detect a stimulus 50 percent of the time

Subliminal Stimulation

Stimuli below the threshold of conscious awareness

Difference Threshold

The minimum difference needed to detect a change between stimuli

Weber’s Law

A principle stating that the just noticeable difference is proportional to the original stimulus intensity

Sensory Adaptation

Diminished sensitivity to constant stimulation

Transduction

The conversion of stimulus energy into neural impulses

Wavelength

The distance between peaks of a wave determining color perception

Feature Detectors

Neurons that respond to specific features such as edges or angles

Parallel Processing

The processing of multiple aspects of a stimulus simultaneously

Blindsight

The ability to respond to visual stimuli without conscious awareness

Young-Helmholtz Trichromatic Theory

The theory that color vision is based on three types of receptors for red green and blue

Opponent Process Theory

The theory that opposing retinal processes enable color vision

Audition

The sense of hearing

Frequency

The number of wave cycles per second determining pitch

Pitch

A tone’s perceived highness or lowness

Conduction Hearing Loss

Hearing loss caused by damage to the mechanical system of the ear

Sensorineural Hearing Loss

Hearing loss caused by damage to the inner ear or auditory nerve

Place Theory

The theory that different sound frequencies activate different places on the cochlea

Frequency Theory

The theory that the rate of nerve impulses matches sound frequency

Volley Theory

The theory that groups of neurons fire in rapid succession to represent high frequencies

Kinesthesis

The sense of body position and movement

Context Effects

The influence of context on perception

Stroboscopic Movement

The perception of continuous motion from a rapid series of images

Phi Phenomenon

The illusion of movement created when lights blink on and off in succession

Gestalt

An organized whole perceived as more than the sum of its parts

Figure-ground

The organization of visual field into objects and background

Grouping

The perceptual organization of stimuli into meaningful groups

Depth Perception

The ability to see objects in three dimensions

Visual Cliff

A laboratory device for testing depth perception

Binocular Cues

Depth cues requiring both eyes

Retinal Disparity

A binocular cue based on the difference between images in each eye

Monocular Depth Cues

Depth cues available to either eye alone

Perceptual Constancy

Perceiving objects as unchanging despite changes in sensory input

Color Constancy

Perceiving consistent color under varying illumination

Perceptual Adaptation

The ability to adjust to altered sensory input

Perceptual Set

A mental predisposition influencing perception

Synesthesia

A condition where stimulation of one sense triggers another

Prosopagnosia

A disorder characterized by difficulty recognizing faces

Accommodation

The process by which the eye’s lens changes shape to focus images

Vestibular Sense

The sense of balance and head movement

Gate-Control Theory

A theory that spinal cord gates control pain signals

Sensory Interaction

The principle that senses influence each other

Nearsightedness

A condition where close objects are seen clearly but distant objects are blurry

Farsightedness

A condition where distant objects are seen clearly but close objects are blurry

Dichromatism

A type of color blindness with only two functioning color receptors

Monochromatism

A condition of complete color blindness

Decibels

A unit measuring sound intensity

Stereophonic Hearing

The ability to determine sound direction with two ears

Phantom Limb

The sensation that an amputated limb is still present