Ch 6 - Sensation and Perception

Sensory Deprivation

a state in which there is little or no sensory stimulation

Selective Attention

the ability to focus on only one stimulus from among all sensory input

Signal Detection Theory

a theory predicting how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise). Assumes there is no single absolute threshold and that detection depends partly on a person's experience, expectations, motivation, and alertness.

Absolute Threshold

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

Just Noticeable Difference

the minimal change in a stimulus that can just barely be detected

Subliminal Messaging & Perception

the unconscious processing of sensory information that occurs when stimuli are presented below the level of conscious awareness

ESP (extrasensory perception)

perception of information by some means other than through the normal processes of sensation

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

Pupil

opening in the center of the iris

Blind spot

the point at which the optic nerve leaves the eye

Rods and cones

two types of photoreceptors that interpret colors in the eye

Afterimage

a visual illusion that occurs when you continue to see an image after you've stopped looking at it

Color blindness

a variety of disorders marked by inability to distinguish some or all colors

Binocular

with two eyes

Monocular

with one eye

Trichomatic Theory

the theory that our color vision is based on three colors (blue, green, red)

Inner ear

contains cochlea, semicircular canals, and vestibular sacs

Outer ear

the outermost part of the ear, consisting of the pinna and the external auditory canal

Auditory canal

the area that sound waves pass through to reach the eardrum

Cochlea

a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses

Loudness

a sound's intensity

Pitch

the highness or lowness of a sound

Timbre

quality of sound

Gustation

pertaining to taste

Taste buds

sensory organs in the mouth that contain the receptors for taste

Olfactory

pertaining to smell

Cutaneous

pertaining to the skin; sense of touch

Gate-control theory

the theory that the spinal cord contains a neurological "gate" that blocks pain signals or allows them to pass on to the brain

Phantom Limb

perceived sensation, following amputation of a limb, that the limb still exists

Kinesthesis

the sense of movement and body position

Equilibrium

A state of balance

Subliminal Perception

the processing of information by sensory systems without conscious awareness