Chapter 3: Sensation And Perception Flashcards
(33 cards)
Sensation
The process of receiving stimulus energies from the external environment and transforming those energies into neural energies
Perception
The process of organizing and interpreting sensory information so that it makes sense
Bottom-up processing
The operation in sensation and perception in which sensory receptor register information about the external enviroment and send it up to the brain for interpretation
Top-down processing
The operation in sensation and perception, launched by cognitive processing at the brain’s higher levels, that allows the organism to sense what is happening and to apply that framework to information from the world
Sensory receptors
Specialized cells that detect stimulus information and transmit it to sensory (afferent) nerves and the brain
Absolute threshold
The minimum amount of stimulus energy that a person can detect
Difference threshold
The degree of difference that must exist between two simuli before the difference is detected
Weber’s law
The principle that two stimuli must differ by a constant minimum percentage (rather than a constant amount) in order to be perceived as different
Signal detection theory
An approach to perception that focuses on decision making about a stimuli in the presence of uncertainty
Selective attention
The act of focusing on a specific aspect of experience while ignoring others
Perceptual set
A predisposition or readiness to perceive something in a particular way
Sensory adaptation
A change in the responsiveness of the sensory system based on average level of surrounding stimulation
Retina
The multilayered light-sensitive surface in the eye that records electromagnetic energy and converts it to neural impulses for processing in the brain
Rods
The receptor cells in the retina that are sensitive to light but not very useful for color vision
Cones
The receptor cells in the retina that allow for color vision
Optic nerve
The structure at the back of the eye, made up of axons of the ganglion cells, that carry visual information to the brain for further processing
Visual cortex
Located in the occipital lobe, the part of the cerebral cortex involved in vision
Feature detectors
Neurons in the brain’s visual system that respond to particular features of a stimulus
Parallel processing
The simultaneous distribution of information across different neural pathways
Trichromatic theory
Theory stating that color perception is produced by three types of cone receptors in the retina that are particularly sensitive to different, but overlapping, ranges of wavelengths
Opponent process theory
Theory stating that cells in the visual system respond to complimentary pairs of red-green and blue-yellow colors; a given cell might be excited by red and inhibited by green, whereas another cells may be excited by yellow and inhibited by blue
Figure-ground relationship
The principle by which we organize the perceptual field into stimuli that stand out (figure) and those that are left over (ground)
Gestalt psychology
A school of though interested in how people naturally organize their perceptions according to certain patterns
Depth perception
The ability to perceive objects 3 dimensionally
