Sensation and Perception

Unit 4 in the Textbook, Basic Concepts of Sensation and Perception, Influences on Perception, Vision: Sensory and Perceptual Processing, Visual Organization and Interpretation, Hearing, The Other Senses

Sensation

the process by which our sensory receptors and nervous system receive and interpret stimuli

Sensory Receptors

sensory nerve endings responding to stimuli

Perception

the process of interpreting sensory information (recognize objects/events)

Bottom-up Processing

Analysis that begins with the sensory receptors

Top-down Processing

constructing perceptions based on past experiences and expectations

Selective Attention

focusing on a particular stimulus

Inattentional Blindness

failing to see visual objects when our attention is elsewhere

Change Blindness

failing to notice changes in the enviorment

Transduction

conversion of stimulus energies into neural impulses

Psychophysics

the study of relationships between the physical characteristics of stimuli and our psychological experience of them

Absolute Thresholds

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

Signal Detection Theory

The theory that we can detect a faint stimulus amid background noise

Subliminal

below one’s absolute threshold for conscious awareness

Weber’s Law

to be perceived as different, two stimuli must differ by a constant percentage

Sensory Adaptation

constant stimulation leads to desensitization

Perceptual Set

a mental predisposition to perceive one thing and not the other

Extrasensory Perception (ESP)

ability to perceive things without the senses (telepathy, clairvoyance)

Cornea

the eye’s clear, protective layer covering the pupil and iris

Pupil

the adjustable opening in the center of the eye

Iris

a ring of muscle tissue that controls the size of the pupil opening

Lens

changes shape to help focus images on the retina

Retina

contains the rods and cones and is the beginning of visual information

Rods

retinal receptors that detect white, black, and gray, necessary for twilight vision

Cones

Retinal receptors that function in the daylight and detect fine detail and color sensations

Optic Nerve

carries impulses to the brain

Blind Spot

No receptor cells are located here, the optic nerve left the eye

Fovea

Central focal point in the retina, around which the cones cluster

Young-Helmholtz Trichromatic Theory

color receptors (red, blue, green) that produce any color when stimulated

Opponent-Process Theory

opposing retinal processes enable color vision

Feature Detectors

Nerve cells in the visual cortex that respond to specific features of the stimulus

Parallel Processing

processing many parts of a problem at the same time

Gestalt

our tendency to organize pieces of info as a whole

Figure-Ground

the organization of the visual field into objects that stand out from their surroundings

Visual Cliff

a laboratory device for testing depth perception

Binocular Cues

a depth cue that depends on both eyes

Monocular Cues

a depth cue that depends on one eye

Phi Phenomenon

an illusion of movement created when two or more adjacent lights blink on and off in quick succession

Perceptual Constancy

perceiving objects as unchanging

Color Constancy

perceiving similar objects as having consistent color

Perceptual Adaptation

the ability to adjust to sensory input

Middle Ear

the chamber between the ear drum and cochlea, contains three tiny bones

Cochlea

coiled, fluid filled tube in the inner ear, the sound waves traveling through trigger nerve impulses

Sensorineural Hearing Loss

hearing loss caused by damage to the cochlea

Conduction Hearing Loss

hearing loss caused by damage to the middle ear bones/eardrum

Place Theory

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

Frequency Theory

the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, enabling us to sense its pitch

Vestibular Sense

our sense of body movement and position that enables our sense of balance

Sensory Interaction

the principle that one sense may influence another

Embodied Cognition

the influence of bodily sensations, gestures, and other states on cognitive preferences and judgements