Chapter Three Flashcards
Sensation
The activation of the sense organs by a source of physical energy
Perception
The sorting out, interpretation, analysis, and integration of stimuli by the sense organs and brain
Stimulus
Energy that produces a response in a sense organ
Psychophysics
The study of the relationship between the physical aspects of stimuli and our psychological experience of them
Absolute Threshold
The smallest intensity of a stimulus that must be present for the stimulus to be detected
Difference threshold
The smallest level of added or reduced stimulation required to sense that a change in stimulation has occurred
Weber’s Law
A basic law of psychophysics stating that a just noticeable difference is a constant proportion to the intensity of an initial stimulus (rather than a constant amount
Adaptation
An adjustment in sensory capacity after prolonged exposure to unchanging stimuli
Retina
The part of the eye that converts the electromagnetic energy of light to electrical impulses for transmission to the brain
Rods
Thin, cylindrical receptor cells in the retina that are highly sensitive to light
Cones
Cone-Shaped, light-sensitive receptor cells in the retina that are responsible for sharp focus and color perception, particularly in bright light
Optic Nerve
A bundle of ganglion axons that carry visual information to the brain
Feature Detector
Specialized neurons that are activated only by visual stimuli having specific features, such as a particular shape or pattern
Trichromatic theory of color vision
The theory that there are three kinds of cones in the retina, each of which responds primarily to a specific range of wavelengths
Opponent-Process theory of color vision
The theory that receptor cells for color are linked in pairs, working in opposition to each other
Sound
The movement of air molecules brought about by a source of vibration
Eardrum
The part od the ear that vibrates when sound waves hit it
Cochlea
A Coiled tube in the ear filled with fluid that vibrates in response to sound
Basilar membrane
A vibrating structure that runs through the center of the cochlea, diving it into an upper chamber and a lower chamber and containing sense receptors for sound
Hair cells
Tiny cells covering the basilar membrane that, when bent by vibrations entering the cochlea, transmit neural messages to the brain
Place theory of hearing
The theory that different areas of the basilar membrane respond to different frequencies
Frequency theory of hearing
The theory that the entire basilar membrane acts like a microphone, vibrating as a whole in response to a sound
Semicircular Canals
Three tube-like structures of the inner ear containing fluid that sloshes through them when the head moves, signaling rotational or angular movement to the brain
Skin Senses
The senses of touch, pressure, temperature, and pain
Gate-control theory of pain
The theory that particular nerve receptors in the spinal cord lead to specific areas of the brain related to pain
Gestalt laws of organization
A series of principles that describe how we organize bits and pieces of information into meaningful wholes
Bottom-up processing
Perception that consists of the progression of recognizing and processing information from individual components of a stimuli and moving to the perception of the whole
Top-Down Processing
Perception that is guided by higher-level knowledge, experience, expectations, and motivations
Depth perception
The ability to view the world in three dimensions and to perceive distance
Perceptual constancy
Our understanding that physical objects are unvarying and consistent even though sensory input about them may vary
Visual illusions
Physical stimuli that consistently produce errors in perception
